Title of Invention: System and method for preparing ester-based composition
technical field
[One]
Cross-Citation with Related Applications
[2]
This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0039715 dated April 4, 2019, and all contents disclosed in the literature of the Korean patent application are incorporated as a part of this specification.
[3]
technical field
[4]
The present invention relates to systems and methods capable of efficiently and continuously preparing ester-based compositions.
background
[5]
Phthalate-based plasticizers accounted for 92% of the global plasticizer market by the 20th century (Mustafizur Rahman and Christopher S. Brazel "The plasticizer market: an assessment of traditional plasticizers and research trends to meet new challenges" Progress in Polymer Science 2004, 29, 1223-1248), mainly used to give flexibility, durability, and cold resistance to polyvinyl chloride (hereinafter referred to as PVC) and to improve processability by lowering the viscosity during melting. From hard products such as pipes to soft products that are soft and stretchable and can be used for food packaging, blood bags, flooring, etc. .
[6]
However, in spite of the compatibility with PVC of phthalate-based plasticizers and excellent softness imparting properties, recently, when PVC products containing phthalate-based plasticizers are used in real life, little by little leakage to the outside of the product causes endocrine disorders (environmental hormones) estimated substances and heavy metal levels. Controversy has arisen that it may act as a carcinogen (NR Janjua et al. "Systemic Uptake of Diethyl Phthalate, Dibutyl Phthalate, and Butyl Paraben Following Whole-body Topical Application and Reproductive and Thyroid Hormone Levels in Humans" Environmental Science and Technology 2008, 42, 7522-7527). In particular, in the 1960s, it was reported that di-(2-ethylhexyl) phthalate (DEHP), the most used phthalate-based plasticizer in the United States, leaked outside PVC products. Global environmental regulations, including various studies on the harmfulness of phthalate-based plasticizers to the human body, began to be implemented.
[7]
Accordingly, many researchers have developed a new non-phthalate-based plasticizer that excludes phthalic anhydride, which is used in manufacturing phthalate-based plasticizers, or suppressed the leakage of phthalate-based plasticizers to respond to environmental hormone problems and environmental regulations caused by the leakage of phthalate-based plasticizers. Research is underway to develop spill control technology that can significantly reduce risks and meet environmental standards.
[8]
On the other hand, as a non-phthalate-based plasticizer, the terephthalate-based plasticizer is not only at the same level in terms of physical properties as the phthalate-based plasticizer, but is also spotlighted as a material free from environmental problems, and various types of terephthalate-based plasticizers are being developed. In addition to research on developing terephthalate-based plasticizers with excellent physical properties, research on facilities for manufacturing such terephthalate-based plasticizers are also being actively carried out. is being requested
[9]
[10]
Prior art literature
[11]
(Patent Document 1) Republic of Korea Patent Publication No. 10-1354141
[12]
(Non-Patent Document 1) Mustafizur Rahman and Christopher S. Brazel "The plasticizer market: an assessment of traditional plasticizers and research trends to meet new challenges" Progress in Polymer Science 2004, 29, 1223-1248
[13]
(Non-Patent Document 2) NR Janjua et al. "Systemic Uptake of Diethyl Phthalate, Dibutyl Phthalate, and Butyl Paraben Following Whole-body Topical Application and Reproductive and Thyroid Hormone Levels in Humans" Environmental Science and Technology 2008, 42, 7522-7527
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[14]
An object of the present invention is to provide a manufacturing system and a manufacturing method capable of continuously manufacturing an ester-based composition efficiently and economically.
means of solving the problem
[15]
The present invention relates to a mixing part in which a reaction mixture of a polycarboxylic acid and a first alcohol is formed, a reaction part in which an esterification reaction of the reaction mixture is performed to form a first crude product mixture containing a first ester compound, the reaction part A trans reaction unit in which a second crude product mixture including a second ester compound is formed by performing a trans-esterification reaction of the first crude product mixture formed in and a second alcohol separately introduced, the second crude product mixture a neutralization section in which an aqueous layer stream and an organic layer stream are formed by performing neutralization and separation of the organic layer stream, a distillation section in which an alcohol-rich stream and an ester-rich stream are formed by distilling the organic layer stream, and the first alcohol remaining in the ester-rich stream and Provided is a system for making an ester-based composition comprising a product refining section for removing the second alcohol to form a mixed alcohol stream comprising a first alcohol and a second alcohol and a product stream.
[16]
[17]
The present invention provides a method for producing an ester-based composition carried out through the above-described production system, specifically, forming a reaction mixture comprising a polycarboxylic acid and a first alcohol (S1), esterification reaction of the reaction mixture to prepare a first crude product mixture containing the first ester compound (S2), trans-esterification reaction of the first crude product mixture and a second alcohol to a second crude product containing the second ester compound preparing a second product mixture (S3), neutralizing and water separation of the second crude product mixture to obtain an aqueous layer stream and an organic layer stream (S4), distilling the organic layer stream to obtain an alcohol-rich stream and an ester-rich stream It provides a method for preparing an ester-based composition comprising the steps of obtaining (S5), and removing the first and second alcohols remaining in the ester-rich stream to obtain a mixed alcohol stream and a product stream (S6).
Effects of the Invention
[18]
When the manufacturing system of the present invention is used, the entire manufacturing process can be continuously operated, so that the ester-based composition can be efficiently and economically manufactured. to prepare an ester-based composition.
Brief description of the drawing
[19]
1 is a schematic diagram of a system for producing an ester-based composition of the present invention, including a mixing unit, a reaction unit, a trans reaction unit, a neutralization unit, a distillation unit, and a product purification unit.
[20]
2 is a schematic diagram of a system for producing an ester-based composition of the present invention, including a mixing unit, a reaction unit, a trans reaction unit, a neutralization unit, a distillation unit, a product purification unit, and a mixed alcohol tank.
[21]
3 is a schematic diagram of a system for preparing an ester-based composition of the present invention, including a mixing unit, a reaction unit, a trans reaction unit, a neutralization unit, a distillation unit, a product purification unit, and a mixed alcohol separation column.
[22]
4 is a schematic diagram of a system for preparing an ester-based composition of the present invention, including a mixing unit, a reaction unit, a trans reaction unit, a neutralization unit, a distillation unit, a product purification unit, a mixed alcohol separation column, and a wastewater treatment unit.
Modes for carrying out the invention
[23]
Hereinafter, the present invention will be described in more detail.
[24]
The terms or words used in the present specification and claims should not be construed as being limited to their ordinary or dictionary meanings, and the inventor may properly define the concept of the term in order to best describe his invention. Based on the principle that there is, it should be interpreted as meaning and concept consistent with the technical idea of ​​the present invention.
[25]
[26]
In the manufacturing method and manufacturing system of the present invention, polycarboxylic acid refers to a compound having two or more carboxylic acid groups, and may mean, for example, dicarboxylic acid, tricarboxylic acid or tetracarboxylic acid. The polycarboxylic acid used in the present invention may have 2 to 5 carboxylic acid groups, 2 to 4 carboxylic acid groups, or 2 to 3 carboxylic acid groups. When the polycarboxylic acid has an excessively large number of carboxylic acid groups, it may not be smoothly applied to the production method or production system of the present invention due to the high molecular weight of the polycarboxylic acid itself. The polycarboxylic acid is particularly preferably dicarboxylic acid, tricarboxylic acid or tetracarboxylic acid. In the case of dicarboxylic acid, one selected from the group consisting of linear dicarboxylic acid having 2 to 10 carbon atoms, terephthalic acid, phthalic acid, isophthalic acid, and cyclohexane dicarboxylic acid. In the case of tricarboxylic acid, it may be at least one selected from the group consisting of citric acid, trimellitate acid and cyclohexane tricarboxylic acid, and in the case of tetracarboxylic acid, benzenetetracarboxylic acid, furantetracarboxylic acid, cyclohexane tetracarboxylic acid, and tetrahydro It may be at least one selected from the group consisting of furan tetracarboxylic acid. In addition, the polycarboxylic acid may include an anhydride or derivative thereof as well as itself.
[27]
[28]
In the manufacturing system and manufacturing method of the present invention, the first alcohol and the second alcohol are alcohols having 3 to 10 alkyl carbon atoms, respectively, and the first alcohol and the second alcohol have different alkyl carbon atoms. Specifically, the alcohol having 3 to 10 alkyl carbon atoms may be at least one selected from the group consisting of linear or branched propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol and decanol. In addition, the first alcohol and the second alcohol may be a single type of alcohol or a mixture containing isomers having the same carbon number. For example, when the first alcohol is an alcohol having 3 alkyl carbon atoms, the first alcohol may be one type of 1-propanol or 2-propanol, or may be in the form of a mixture containing 1-propanol and 2-propanol in a certain ratio. have. When the first alcohol and the second alcohol are in the form of a mixture including isomers having the same carbon number, the relative amount between each isomer is not particularly limited.
[29]
In addition, in the manufacturing system and manufacturing method of the present invention, the lower alcohol and the higher alcohol refer to an alcohol having a small carbon number and an alcohol having a large carbon number among the first alcohol and the second alcohol used in the present invention, respectively. For example, if propanol is used as the first alcohol and nonanol is used as the second alcohol, the lower alcohol refers to the first alcohol propanol, the higher alcohol refers to the second alcohol nonanol, and hexanol is the first alcohol and, when butanol is used as the second alcohol, the lower alcohol refers to butanol as the second alcohol, and the higher alcohol refers to hexanol as the first alcohol.
[30]
[31]
In the production system and production method of the present invention, the first ester compound refers to an ester compound formed by esterification of a first alcohol and a polycarboxylic acid. Specifically, in the first ester compound, at least one of a plurality of carboxylic acid groups included in the polycarboxylic acid reacts with the first alcohol to form an ester bond, and more specifically, one of the carboxylic acid groups included in the polycarboxylic acid; Two or more reacted with the first alcohol to form an ester linkage.
[32]
In the production system and production method of the present invention, the second ester compound refers to an ester compound formed by trans-esterification of a second alcohol and a first ester compound. Specifically, in the second ester compound, at least one of a plurality of ester groups included in the first ester compound is trans-esterified with a second alcohol, and more specifically, among the ester groups included in the first ester compound One, two or more are trans-esterified with a second alcohol.
[33]
[34]
In this specification, equipment described to describe a manufacturing system, for example, a column, a still, a neutralizer, or a wastewater treatment tank, means "upper" means, unless specifically specified, the upper end of each equipment. Including the surface, it may include a side upper cross-section positioned upward from the center in the height direction of the side, and the meaning of "lower" is also, unless specifically specified, including the lower surface, of the side It may include a lower side cross-section located downward from the center in the height direction.
[35]
[36]
In the manufacturing system and manufacturing method of the present invention, a stream refers to a flow of a fluid moving from one component constituting the system to another component in the system or to the outside of the system, and the fluid includes both gas and liquid. .
[37]
[38]
The system for producing the ester-based composition of the present invention may be continuously operated. As will be described later, since all components constituting the manufacturing system of the present invention are capable of continuous operation, the overall continuous operation of the manufacturing system is possible, and therefore, when the manufacturing system of the present invention is used, the final product, That is, there is an advantage that an ester-based composition can be prepared. In the present invention, “continuous” means that each component or step can be operated or performed simultaneously.
[39]
[40]
Ester-based composition manufacturing system
[41]
The present invention relates to a mixing part in which a reaction mixture of a polycarboxylic acid and a first alcohol is formed, a reaction part in which an esterification reaction of the reaction mixture is performed to form a first crude product mixture containing a first ester compound, the reaction part A trans reaction unit in which a second crude product mixture including a second ester compound is formed by performing a trans-esterification reaction of the first crude product mixture formed in and a second alcohol separately introduced, the second crude product mixture a neutralization section in which an aqueous layer stream and an organic layer stream are formed by performing neutralization and separation of the organic layer stream, a distillation section in which an alcohol-rich stream and an ester-rich stream are formed by distilling the organic layer stream, and the first alcohol remaining in the ester-rich stream and Provided is a system for making an ester-based composition comprising a product refining section for removing the second alcohol to form a mixed alcohol stream comprising a first alcohol and a second alcohol and a product stream.
[42]
[43]
As shown in Figure 1, the production system of the ester-based composition of the present invention is largely a mixing unit (1), a reaction unit (2), a trans reaction unit (3), a neutralization unit (4), a distillation unit (5) and Consists of the product refining unit 6, each component constituting the production system of the ester-based composition of the present invention will be described in more detail with reference to the drawings below.
[44]
[45]
mixing part
[46]
In the production system of the ester-based composition of the present invention, the mixing unit 1 is a region in which the first alcohol corresponding to the reaction raw material and the polycarboxylic acid are mixed. The first alcohol 11 and the polycarboxylic acid 12 are added to the mixing section, and are mixed in the inner region of the mixing section to form the reaction mixture 13 .
[47]
In the production system of the ester-based composition of the present invention, the esterification reaction of the first alcohol and the polycarboxylic acid and the trans-esterification reaction of the first ester compound and the second alcohol are performed, and each reaction is a state in which the reaction raw materials are uniformly mixed Since it is performed more smoothly in the subsequent reaction section, it is necessary to evenly mix the first alcohol and polycarboxylic acid prior to the esterification reaction.
[48]
If the reaction raw materials are not mixed and put into the reactor in advance as described above, the non-uniformity of the raw materials may greatly increase depending on the location inside the reactor, and in particular, when the stirring inside the reactor is not good, some raw materials may be accumulated. Difficulty may arise in securing time uniformly. On the other hand, when the reaction raw materials are mixed and added in advance, a substantially uniform degree of reaction can be obtained over the entire region of the reactor, and the reaction rate of each reactor can be maintained substantially uniformly to ensure the stability of the entire process.
[49]
The mixing unit in the present invention is not particularly limited as long as it is for smoothly mixing the first alcohol and the polycarboxylic acid, and may include, for example, a mixing device such as a stirrer or a mixer. One mixing device may be included in the mixing unit, or a plurality of mixing devices may be included.
[50]
The mixing unit in the present invention may further include a heating means in addition to the mixing device. Since the esterification reaction in the reaction unit is performed at a relatively high temperature, if the reaction mixture is heated in advance in the mixing unit before being introduced into the reaction unit and then added to the reaction unit, the reaction can be started within a short time after the introduction into the reaction unit. There is an advantage that A heat exchanger or a heater may be used as the heating means, and the first alcohol, polycarboxylic acid and/or reaction mixture is not particularly limited as long as it can be smoothly heated. When the mixing unit includes the heating means, the temperature of the reaction mixture in the mixing unit may be 50 to 200°C, preferably 60 to 190°C, more preferably 70 to 180°C. When the temperature of the reaction mixture is too low, it may be rather uneconomical because the effect of heating it up in advance in the mixing part is small and inputting it into the reactor. This may occur, so that a uniform reaction cannot proceed, or a loss of reaction raw materials may occur.
[51]
[52]
reaction part
[53]
The reaction mixture 13 formed in the mixing unit is then introduced into the reaction unit 2, where an esterification reaction of the reaction mixture is performed to form a first crude product mixture.
[54]
[55]
Specifically, in the reaction unit, an esterification reaction between the polycarboxylic acid and the first alcohol included in the reaction mixture is performed. The esterification reaction is a reaction in which a carboxylic acid group and a hydroxyl group form an ester bond and water, and through the reaction reaction, at least one carboxylic acid group of a polycarboxylic acid reacts with a first alcohol to form a first ester compound. Accordingly, the first crude product mixture formed in the present reaction unit contains the first ester compound.
[56]
[57]
The esterification reaction in the reaction part may have some differences depending on the type of the first alcohol and polycarboxylic acid, but may be carried out under general temperature and pressure conditions of the esterification reaction, and the presence of a catalyst widely used in the esterification reaction can be carried out under A person skilled in the art may determine the temperature and pressure conditions of the reaction unit, the type and amount of catalyst, and the like in consideration of the type or amount of the polycarboxylic acid and the first alcohol.
[58]
[59]
On the other hand, the reaction unit may be provided with a plurality of reactors, and more specifically, (1) having a plurality of reactors connected in series, or (2) having a plurality of reactors connected in parallel.
[60]
[61]
(1) When a plurality of reactors connected in series are provided
[62]
According to an embodiment of the present invention, the reaction unit includes N reactors and a variable control unit connected in series of the first to Nth reactors, and the variable control unit includes the temperature of each reactor such that the following equations 1) and 2) are satisfied. and to control the amount of alcohol introduced into each reactor, wherein N may be an integer of 2 or more:
[63]
1) T n1-1 ≤T n1
[64]
2) E n2-1 ≥E n2 ≥E 1
[65]
In the formula, n1 is an integer from 2 to N, n2 is an integer from 3 to N,
[66]
T x = temperature of the xth reactor
[67]
E x = {(number of moles of alcohol input to the xth reactor - c*number of moles of polycarboxylic acid injected into the xth reactor/c*number of moles of polycarboxylic acid injected into the first reactor)*100%}
[68]
In the T x and E x , x is an integer of 1 to N,
[69]
Where c is the number of carboxylic acid groups included in one molecule of polycarboxylic acid.
[70]
[71]
When the reaction unit consists of a plurality of series-connected reactors instead of one reactor, the process design cost can be reduced by reducing the size of each reactor, and the reaction mixture can be continuously introduced into a plurality of series-connected reactors, Process parameters for each reactor can be independently adjusted to enable optimization of the entire process. In addition, ultimately, it is possible to maximize the efficiency of the overall ester-based composition manufacturing system.
[72]
[73]
In particular, in the case of connecting the N reactors included in the reaction part in series, the inventor of the present invention adjusts the temperature of each reactor and the E value in each reactor as in Equations 1) and 2) above, the ester-based composition It was found that the overall optimization of the production system of It was confirmed that the amount can also be maximized.
[74]
The E value is based on “the amount of the first alcohol required for 100% reaction of the initially added polycarboxylic acid”, compared to “the amount of the first alcohol required for 100% reaction of the polycarboxylic acid introduced into each reactor” It means the ratio of "the amount of the first alcohol to be added". The amount means an amount based on moles. For example, if the polycarboxylic acid is a dicarboxylic acid, 100 moles of the dicarboxylic acid are added to the reactor, and 300 moles of alcohol is added, the alcohol for 100% reaction of the dicarboxylic acid is 200 moles, so 100 moles of additionally added alcohol is , the ratio of E value corresponds to 50% in the ratio of 100 moles to 200 moles.
[75]
Meanwhile, the lower limit of E 1 may be -30%, -20%, -10%, 0% or 10%, and the upper limit of E 1 may be 80%, 70%, 60%, 50% or 40%. . The lower limit of E N may be 0%, 10% or 20%, and the upper limit of E N may be 80%, 70%, 60%, 50% or 40%. When E 1 and E N are too few or too many, the two reaction raw materials are out of balance, and some of the reaction raw materials are wasted, and the composition in the maximum amount may not be prepared. In particular, when the E value of the first reactor is too high, the amount of alcohol that is excessively added from the beginning may be large, and a large amount of alcohol that does not participate in the actual reaction may be generated. In this case, the desired degree of conversion may not be achieved, or the actual reaction Too much energy is consumed to heat even the alcohol that cannot participate in the reaction, which may cause a problem in which the efficiency of the overall reaction process decreases. In addition, due to the volume occupied by the excess alcohol of a certain amount or more in the reactor, it may lead to a decrease in the production amount of the finally manufactured ester-based composition product.
[76]
[77]
In the reaction unit, the lower limit of T 1 may be 100°C, 120°C, 140°C, 160°C or 180°C, and the upper limit of T 1 may be 220°C or 200°C. In addition, the lower limit of T N may be 140 ℃, 160 ℃, 180 ℃, 200 ℃ or 220 ℃, the upper limit of T N may be 220 ℃, 230 ℃, 240 ℃ or 250 ℃. If T 1 and T N are too low, sufficient heat may not be supplied for the reaction and thus a sufficient conversion rate may not be obtained.
[78]
[79]
On the other hand, the variable control unit serves to control the temperature and E value in each reactor. Specifically, in terms of temperature control, the variable control unit may be provided with a means for controlling the temperature by adjusting the amount of steam consumed for heating each reactor. In addition, in terms of controlling the E value, the variable control unit 1) controls to remove a portion of the alcohol or to inject a portion of the alcohol between each reactor when the reaction mixture continuously passes through the reactors, or 2) to be described later Controlling the input path and input amount of the first alcohol stream formed from the mixed alcohol separation column, or 3) having a means for controlling a portion of the alcohol refluxed in each reactor to be removed or a portion of the alcohol added can In the case of 1), the variable control unit may be a pressure reducing device that is provided between a plurality of series-connected reactors to selectively remove alcohol, or a pump capable of additionally introducing alcohol between the reactors. . In the case of 2), the variable control unit is a transfer pipe connecting the mixed alcohol separation column and each reactor, and may include a pump capable of controlling the input amount to each connected reactor. In the case of 3), the variable control unit may be a decompression device or pump that is further connected to a reflux system connected to the reactor to partially remove alcohol in the reflux process or to additionally add some alcohol. In addition to the devices listed above, other devices known to those skilled in the art can be used as the variable control unit of the present invention, as long as they can perform the function of controlling the E value and temperature of each reactor.
[80]
[81]
In the case of applying the reaction part as described above, N may be an integer of 2 or more, preferably an integer of 3 or more, and more preferably an integer of 3 to 10, or 3 to 7, or 3 to 5. can When the number of reactors is less than this, the technical advantage of arranging a plurality of reactors in series does not appear sufficiently. It may increase the cost, which may not be effective in terms of the overall cost of the process.
[82]
[83]
(2) When a plurality of reactors connected in parallel are provided
[84]
According to another embodiment of the present invention, the reaction unit includes N reactors and a supply control unit connected in parallel of a first reactor to an Nth reactor, and the supply control unit forms a first crude product mixture in each reactor The input amount and the input route of the reaction mixture introduced from the mixing unit to the reaction unit are controlled so as to be semi-continuous over the N reactors, and N may be an integer of 2 or more.
[85]
[86]
When a plurality of batch reactors are used in a conventional general reaction process, they are arranged in parallel so that the reaction raw materials are simultaneously introduced into the plurality of batch reactors, and the reaction is performed simultaneously in each batch reactor after all the reaction raw materials are input . In this case, when the reaction is carried out, the input of raw materials into the batch reactor is stopped, and after all the reactions of each batch reactor are completed, the reaction products are discharged from all the batch reactors at the same time, and in this process, the reaction in the reactor is also not performed. does not Therefore, a complete continuous manufacturing process could not be realized with a batch reactor, and in particular, in the case of a reaction process using a conventional batch reactor, a large amount of reaction products could be stably prepared at one time, but the reaction raw materials were input or the reaction products In this discharge process, the reactor was not operated, so there was a disadvantage in terms of the efficiency of the entire process.
[87]
Accordingly, the inventor of the present invention confirmed that the reaction product can be continuously produced while maintaining the stability of the batch reactor by allowing a plurality of batch reactors to be used sequentially, that is, semi-continuously as in the above embodiment. .
[88]
[89]
Specifically, when using the reaction unit according to the embodiment, the reaction mixture is sequentially introduced into N reactors, each reactor to which the reaction mixture is introduced is heated to complete the reaction, and each reactor in which the reaction is completed also reacts in sequence discharge the product.
[90]
Illustratively, the reaction unit may be operated in the following manner:
[91]
1) The reaction mixture uniformly mixed in the mixing unit is introduced into the first reactor, and the input into the first reactor is stopped after a predetermined amount of the reaction mixture is inputted.
[92]
2) After the time when the input is stopped, the first reactor is heated to perform the reaction, and the mixing unit introduces the reaction mixture into the second reactor.
[93]
3) After the predetermined amount of the reaction mixture is added to the second reactor, the input to the second reactor is stopped. After this point, the temperature of the second reactor is raised to perform the reaction, and the mixing unit introduces the reaction mixture into the third reactor.
[94]
4) In this way, the N reactors sequentially prepare a reaction product, and after the reaction mixture into the Nth reactor is completed, the reaction mixture is again introduced into the first reactor. In addition, in the case of the reaction product prepared after the reaction is completed, it is sequentially discharged in the same manner.
[95]
[96]
In addition, the supply control unit takes the reaction time in one reactor and N, which is the total number of reactors, as input values, from starting the reaction mixture into the first reactor until starting the reaction mixture into the second reactor. Using the time interval as the output value, the outputted time interval is controlled so that the input path of the reaction mixture is changed from the previous reactor to the next reactor, and the time interval is 90% to 110% of the value obtained by dividing the reaction time by N can
[97]
[98]
The supply control unit in the production system of the present invention must determine the input route of the reaction mixture so that the N reactors can function sequentially. After completion, the input of the reaction mixture into the corresponding reactor is started again when all or almost all of the reaction products are discharged, so that all reactors can be operated without gaps, and the efficiency of the process can be increased.
[99]
[100]
The above-mentioned reaction time is the sum of the time consumed for the reaction and the time consumed for the input of the reaction mixture and the discharge of the reaction product. For example, when 30 minutes are consumed for the reaction and 15 minutes are consumed each for the input of the reaction mixture and the discharge of the reaction product, the reaction time is 60 minutes. If there are 4 reactors in this case, the dosing time interval for each reactor is 15 minutes, and the dosing of the reaction mixture to each reactor is started every 15 minutes.
[101]
[102]
In the case of applying the reaction unit as described above, since the reaction unit simultaneously performs input of the reaction mixture into each reactor, temperature increase and reaction, and discharge of the reaction product, at least one of the plurality of reactors continuously generates the reaction mixture The input is received, and at least one other reactor performs the reaction, and at least one other reactor must discharge the reaction product. Accordingly, N may be an integer of 2 or more, preferably an integer of 3 or more, and more preferably an integer of 3 to 10, 3 to 7, or 3 to 5. When the number of reactors is too large, various additional equipment and equipment are required, including a supply control unit for controlling that the reaction mixture is introduced into each reactor in order and the reaction product is discharged from each reactor, as well as one reactor. The unit reaction time of the reactor may be shorter than the sum of the input time of the raw material input to the reactor and the discharge time of the reaction product, so that the reactor does not operate until the raw material is input, and as a result, the productivity is adversely affected. can In addition, the space required for disposing each reactor may also be excessive, which may not be efficient in terms of the overall cost of the process.
[103]
[104]
Meanwhile, in both the case where the reaction unit includes a plurality of reactors connected in series and the case where the reaction unit includes a plurality of reactors connected in parallel, each reactor may be provided with a reflux system. Since the temperature at which the esterification reaction is performed is a temperature at which the first alcohol and water, which is a by-product of the esterification reaction, can be vaporized, continuous vaporization of the first alcohol and water occurs during the reaction. The vaporization of the first alcohol as a raw material for the reaction lowers the concentration of the first alcohol in the reaction mixture, which causes a decrease in the reaction rate. Therefore, it is necessary to re-liquefy the vaporized first alcohol and put it into the reactor, and a reflux system for this may be provided in each reactor.
[105]
Specifically, the reflux system is connected to the upper part of the reactor, a gas-liquid separation column in which alcohol and water discharged through the upper part of the reactor are separated, a condenser for cooling the gas discharged through the upper line of the gas-liquid separation column, and a gas-liquid separation column. It may be provided with a decanter for recirculating alcohol to the reactor by layer separation of the liquid discharged through the lower line and the liquid condensed in the condenser.
[106]
As described above, when the reactor is equipped with a reflux system, it is possible to increase the efficiency and economy of the reaction by liquefying the alcohol, which is an opportunity during the reaction, and re-injecting it into the reactor, and at the same time, by removing water, a by-product of the esterification reaction. It is possible to allow the reaction to proceed towards the forward reaction, ie to achieve a high conversion rate.
[107]
[108]
trans reaction part
[109]
The first crude product mixture formed in the above-described reaction unit is then trans-esterified with the second alcohol 31 in the trans reaction unit 3 .
[110]
[111]
Specifically, a trans-esterification reaction is performed between the first ester compound included in the first crude product mixture and the second alcohol added separately, and as a result, the second crude product mixture 32 containing the second ester compound ) is formed.
[112]
The second alcohol may be directly added to the trans reaction unit, or may be directly added to and mixed with the first crude product mixture before the first crude product mixture is added to the trans reaction unit.
[113]
Two or more types of ester compounds may be included in the ester-based composition finally obtained through the trans-esterification reaction in the present trans reaction unit.
[114]
If the present trans reaction unit is for performing the trans-esterification reaction of the first crude product mixture and the second alcohol, the type or shape of the device is not particularly limited, and the above-described reaction unit is also applied as the trans reaction unit of the present invention. can For example, the trans reaction unit may be a single reactor or a plurality of reactors connected in series or in parallel, and may include heating means for controlling the temperature in the reactor.
[115]
[116]
Chinese Ministry
[117]
The second crude product mixture prepared in the preceding trans reaction unit is then transferred to the neutralization unit 4 to be subjected to neutralization and water separation, and as a result, an aqueous layer stream 42 and an organic layer stream 41 are formed.
[118]
[119]
In the case of the process of purifying the product of the existing esterification reaction, when the reaction is completed, neutralization is performed to preferentially deactivate the catalyst, and after neutralization, extraction of alcohol has been performed under reduced pressure in a reactor or distillation apparatus in which the esterification reaction is performed. This is a method for separating unreacted alcohol from an ester product, and has an advantage in that it has high efficiency and has been generally performed. In addition, it is common for water to be removed to the top of the equipment together with the alcohol mixture in that extraction under reduced pressure is performed after neutralization on the structure of the equipment.
[120]
As such, when water is mixed and separated with an alcohol mixture, particularly an alcohol having a low carbon number, the separation is quite difficult because the alcohol having a low carbon number has a large solubility in water, and the total amount of the alcohol exceeds about 3.0% by weight. If it is not properly treated, it may be classified as a serious level of wastewater and cause problems, and there is a problem that considerable cost and energy are required to treat it. In addition, in an effort to reduce the alcohol content in the wastewater, a dealcoholization process of extracting unreacted alcohol under reduced pressure immediately after the reaction is completed is performed.
[121]
Accordingly, in the manufacturing method according to the present invention, a neutralizer having a barrier rib structure is introduced into the neutralization unit, and through the introduction of the neutralizer, the water separation process (layer separation) can be performed to a significant degree along with the neutralization process. In the case of neutralization and water separation through the neutralizer according to the present invention, the alcohol mixture can be sent to the organic layer rich in esters, thereby minimizing the alcohol, particularly the lower alcohol, flowing into the water layer. Specifically, the neutralization unit includes one or more neutralizers, and the internal space of the neutralizer is provided with one or more partition walls such that the neutralization space and the layer separation space are respectively divided in the left and right directions to form a passage connecting the two spaces. , the passage may be one starting from the top of the neutralization space.
[122]
[123]
In the past, water and alcohol had to be separated in the absence of an ester, but according to the present invention, the alcohol contained in water is minimized because it is possible to induce the alcohol into the organic layer by layer separation in the presence of the ester. have the advantage of being able to The water layer separated as described above may contain 0.5 to 3.0 parts by weight of alcohol based on 100 parts by weight of the mixed weight of water and alcohol. Substantially, it may be 2.0 parts by weight or less, and more substantially, it may be 1.0 parts by weight or less, and the alcohol content in the wastewater may be reduced compared to the existing process.
[124]
Meanwhile, in the purification step according to the present invention, the second crude product mixture may include 50 to 95 parts by weight of ester and 5 to 50 parts by weight of alcohol, and since the process of removing unreacted alcohol was not performed, The content of the alcohol component may be somewhat higher than the product ester.
[125]
[126]
According to an embodiment of the present invention, since the neutralizer has a partition structure, the entire process can be continuously operated. Although the structure of the partition wall structure is not particularly limited, at least one partition wall needs to be installed so that a space is divided into at least two spaces inside the neutralizer and a passage connecting the two spaces can be provided.
[127]
Specifically, the neutralizer includes a first space provided on the inlet side and a second space provided on the organic layer stream outlet side, and the passage between the two spaces is provided in the vertical direction so that the upper part of the neutralization space and the lower part of the separation space are connected. , the one or more partition walls may form the passage. In addition, the neutralizer may further include a neutralizing agent inlet through which the neutralizing agent is introduced into the first space and a waste liquid treatment port discharged from the second space.
[128]
In addition, the organic layer stream of the neutralizer and the inlet stream (inlet) of the neutralizer through which the crude product mixture flows may be one in which mutual heat exchange is performed. Although the neutralization reaction is an exothermic reaction, the crude product mixture that has finished the esterification reaction needs cooling because it is introduced at a high temperature due to the high reaction temperature. Since this is required, energy consumption can be reduced by utilizing unnecessary heat of the inlet stream of the neutralizer as heat required for the outlet stream.
[129]
According to an embodiment of the present invention, the neutralization of the second crude reaction product is performed in the neutralizer, and a neutralizing agent for neutralization may be added. The neutralizing agent may be an aqueous base solution having a base concentration of 0.1 to 50% by weight, for example, sodium hydroxide or sodium hydrogen carbonate aqueous solution. As a neutralizing agent, an aqueous base solution having the same base concentration as described above may be used, but both neutralization of the catalyst and neutralization of the reaction product may be performed. Accordingly, the salt generated from the neutralization can be discharged through the waste liquid treatment port.
[130]
The second crude product mixture is fed to a neutralizer, so that both the catalyst and the reaction product can be neutralized by an aqueous base solution as a neutralizing agent, and can be separated into an organic layer stream and an aqueous layer stream, wherein the organic layer stream is rich in ester but alcohol may contain, and the aqueous stream is rich in alcohol and may be entrained in very trace amounts of esters.
[131]
Here, the organic layer stream may include 50 to 95 parts by weight of an ester and 5 to 50 parts by weight of an alcohol, and most alcohols may be separated in the neutralization and water separation process, and the alcohol is the first alcohol and the second alcohol. However, most of them are higher alcohols, and the lower alcohols are more hydrophilic than esters or higher alcohols, so they can be mostly separated into an aqueous layer.
[132]
In addition, separated first and second spaces and passages are formed due to the partition wall of the neutralizer, and in the first space, the inflowing second crude product mixture is neutralized with an aqueous base solution to form a salt, and a passage to the second space is formed. Layer separation can be induced by moving it by a certain amount. As the layers are separated in the second space, the organic layer continuously rises so that the organic layer stream can be discharged from the upper end of the second space, and the aqueous layer stream containing salt and lower alcohol is discharged through the waste liquid treatment port provided in the lower part of the second space. can
[133]
Neutralization and water separation performed in the neutralizer may be carried out in the range of about 30 to 150 ℃, the capacity of the neutralizer may be about 5 to 300 m 3 , and other features not mentioned in this specification, such as flow rate Matters applied in the art may be applied without particular limitation.
[134]
[135]
distillery
[136]
The aqueous layer stream 42 formed by neutralizing and water separation of the second crude product mixture in the preceding neutralization unit 4 and the organic layer stream 41 of the organic layer stream 41 are then transferred to the distillation unit 5, and the distillation unit The first and second alcohols remaining in the are removed in the form of an alcohol-rich stream (52) to form an ester-rich stream (51).
[137]
[138]
The distillation unit may be applied to a column, but vacuum extraction may be applied in a drum-type facility, and may be applied without particular limitation as long as it is a facility capable of removing alcohol. In addition, when a column is installed, a buffer tank can be installed as an additional facility at the front end, but preferably, by installing a facility such as a drum-type flash drum, it functions to control the loading amount of the product refining unit at the rear end. may be doing
[139]
That is, the organic layer stream formed in the preceding neutralization unit may contain esters such as the first ester compound and/or the second ester compound, the first alcohol, and the second alcohol. It can have the advantage of being able to easily separate only this low lower alcohol with little energy, and at the same time control the loading amount of the product refining unit at the rear end.
[140]
At this time, the alcohol-rich stream separated into the upper part of the distillation unit may contain 50 to 100 parts by weight of lower alcohol and 0 to 50 parts by weight of higher alcohol relative to 100 parts by weight of the total material in the stream, and the ester-rich stream separated into the lower part. may contain 50 to 99 parts by weight of the ester and 1 to 50 parts by weight of the higher alcohol based on 100 parts by weight of the total material in the stream.
[141]
The distillation unit may have a capacity of about 10 to 300 m 3 , and separation may be performed at about 30 to 200° C., and pressure conditions may be applied from normal pressure to a reduced pressure level of 10 mmHg. This range is a level at which the purification process can be performed normally and efficiently, and when the above range is satisfied, efficient distillation can be performed.
[142]
[143]
product refining department
[144]
The ester-rich stream of the alcohol-rich stream 52 and the ester-rich stream 51 formed in the distillation unit is then sent to the product refining unit 6, and traces of the first alcohol and the second alcohol remaining in the ester-rich stream are The stream comprising the remaining esters removed even in the form of a mixed alcohol stream 62 is obtained as the final product, ie product stream 61 .
[145]
[146]
In the product refining unit of the present invention, even the alcohol remaining in a trace amount in the ester-rich stream may be removed to the top and the ester-based composition to be commercialized may be separated to the bottom. Distillation using steam may also be performed in the present product refining unit, and the product refining unit may be in the form of a column or a drum, but may preferably be a column.
[147]
The product refining unit may have a capacity of 10 to 300 m 3 , may be performed at 30 to 200° C., and pressure conditions may be applied from normal pressure to a reduced pressure level of 10 mmHg. This range is a level at which the purification process can be performed normally and efficiently, and when the above range is satisfied, efficient purification can be performed.
[148]
The product stream separated to the lower part in the product refining unit is commercialized, and the mixed alcohol stream separated to the upper part may be transferred to a mixed alcohol tank or a mixed alcohol separation column to be described later for use.
[149]
[150]
In addition to the above-described mixing section, reaction section, trans reaction section, neutralization section, distillation section and product purification section, the production system of the ester-based composition provided by the present invention is a mixed alcohol tank (7), a mixed alcohol separation column (8) and / Or it may further include a wastewater treatment unit (9).
[151]
[152]
mixed alcohol tank
[153]
As described above, an alcohol-rich stream may be formed in the distillation unit, and a mixed alcohol stream formed in the product refining unit may be formed, and a relatively large amount of the first alcohol and the second alcohol may be present in the alcohol-rich stream and the mixed alcohol stream. Included. Therefore, when it is separately separated and used as a reaction raw material, the overall economic efficiency and efficiency of the process can be improved.
[154]
Accordingly, as shown in FIG. 2, the system for producing the ester-based composition of the present invention may further include a mixed alcohol tank for receiving and storing the mixed alcohol stream and the alcohol-rich stream. The mixed alcohol tank serves to store the first alcohol and the second alcohol in the mixed alcohol stream and the alcohol-rich stream without separating them, and may then be appropriately treated and used as necessary.
[155]
For example, the mixture of the mixed alcohol stream and the alcohol-rich stream stored in the mixed alcohol tank may be transferred to the mixed alcohol separation column in the form of a first recovered alcohol stream as described below.
[156]
The mixed alcohol tank is not particularly limited in size or shape as long as it can perform the function of storage, and a drum or tank shape widely used in the reaction process field may be applied.
[157]
[158]
Mixed Alcohol Separation Column
[159]
As described in the mixed alcohol tank part, it is necessary to utilize the first alcohol and the second alcohol remaining in the alcohol-rich stream and the mixed alcohol stream, and it is directly introduced into the mixed alcohol separation column to separate the first alcohol and the second alcohol can do it Accordingly, as shown in FIG. 3 , the production system of the present invention may further include a mixed alcohol separation column 8 .
[160]
[161]
Specifically, the mixed alcohol separation column 8 receives the alcohol-rich stream formed in the distillation unit and the mixed alcohol stream formed in the product purification unit to form a first recovered alcohol stream (not shown), and the first recovered alcohol to separate the stream into a water stream (83), a first alcohol stream (81) and a second alcohol stream (82). The first recovered alcohol stream refers to a stream in the mixed alcohol separation column and is not separately shown in the drawings.
[162]
[163]
The mixed alcohol separation column should be capable of separating water, the first alcohol, and the second alcohol from each other, and may be, for example, in the form of a distillation column. In addition, the distillation column may be designed in multiple stages to accurately separate each material. In addition, if it is an apparatus capable of separating a mixture in a liquid state by a difference in boiling point, it may be applied to the mixed alcohol separation column of the present invention without any particular limitation.
[164]
[165]
The first alcohol and the second alcohol separated in the mixed alcohol separation column may then be used as a reaction raw material by being added to the reaction unit or trans-reaction unit, and may be separately obtained and utilized in a separate manufacturing system other than the manufacturing system of the present invention. may be When the separated first alcohol stream and the second alcohol stream are utilized again in the production system of the present invention, they may be directly introduced into the reaction section and the trans-reaction section, respectively, and the mixing section prior to that or the first crude product mixture may be put into In addition, the higher alcohol among the first alcohol and the second alcohol may be introduced into a wastewater treatment unit to be described later and used as an additive. On the other hand, the water stream may be discharged directly as wastewater or may be input to a wastewater treatment unit to be described later to be subjected to wastewater treatment.
[166]
[167]
On the other hand, the mixed alcohol separation column may be one in which the alcohol-rich stream and the mixed alcohol stream are directly input from the distillation unit and the product purification unit, respectively, or may be mixed in advance through the mixed alcohol tank described above and then input. When it is introduced through the mixed alcohol tank, since the alcohol-rich stream and the mixed alcohol stream are pre-mixed and introduced, separation in the mixed alcohol separation column can be smooth, and the temperature control before input to the mixed alcohol separation column is also easy There is an advantage that
[168]
[169]
wastewater treatment unit
[170]
As shown in FIG. 4 , the system for preparing the ester-based composition of the present invention may further include a wastewater treatment unit 9 in addition to the above-described mixed alcohol separation column. The wastewater treatment unit receives the water stream 42 of the neutralization unit and the water stream 83 separated in the mixed alcohol separation column to form a preliminary wastewater stream, and a high-grade alcohol having a greater carbon number among the first alcohol and the second alcohol. Alcohol 91 may be added to the preliminary wastewater stream to form a second recovered alcohol stream 92 comprising a first alcohol and a second alcohol and a wastewater stream 93 .
[171]
[172]
The higher alcohol added to the wastewater treatment unit serves as an additive to separate the lower alcohol dissolved in water with high solubility, and the lower alcohol is dissolved in the higher alcohol added instead of water, so that the lower alcohol in the water The alcohol content is reduced. The lower alcohol dissolved in the higher alcohol instead of water, that is, the second recovered alcohol stream, exists in a mixed state of the higher alcohol and the lower alcohol, and the higher alcohol and the lower alcohol are used as the first reaction raw material in the production system of the present invention. Since it corresponds to the alcohol and the second alcohol, it can be used again in the present invention through subsequent treatment. Meanwhile, as described above, as the higher alcohol additionally added to the wastewater treatment unit, a higher alcohol among the first alcohol and the second alcohol separated in the mixed alcohol separation column may be used.
[173]
[174]
The wastewater treatment unit performs layer separation using the low solubility between water and higher alcohol, and a layer separator facility used in the reaction process field may be applied. If the device is equipped with such a separation principle that the organic phase and the aqueous phase do not mix smoothly, it can be applied to the wastewater treatment unit of the present invention without any particular limitation. More specifically, the equipment having substantially the same structure as the above-described neutralization unit may also be applied to the wastewater treatment unit.
[175]
The second recovered alcohol stream formed in the wastewater treatment unit of the present invention may be transferred back to the previous mixed alcohol tank or mixed alcohol separation column to be utilized. In addition, in the wastewater stream formed through this wastewater treatment unit, the lower alcohol may be present in 3.0 wt% or less, 0.01 to 3.0 wt%, 0.01 to 2.0 wt%, or 0.01 to 1.0 wt%, based on the total weight of the wastewater stream, and substantially may be the absence of lower alcohols in the wastewater stream.
[176]
[177]
catalyst input
[178]
The system for preparing the ester-based composition of the present invention may further include a catalyst input unit. Both the esterification reaction and the trans-esterification reaction performed in the production system of the present invention can be performed more smoothly in the presence of a catalyst, and thus the catalyst is directly introduced into the reaction unit and the trans reaction unit, or introduced into the reaction unit or the trans reaction unit. A catalyst input unit may be further included for introducing the catalyst into the pre-reaction mixture or the first crude product mixture.
[179]
[180]
The specific shape and location of the catalyst input unit may vary depending on the type or state of the catalyst to be used, but within the scope of implementing the function of injecting the catalyst into the reaction mixture or the first crude product mixture, those skilled in the art can add the catalyst The shape or position of the part can be appropriately selected.
[181]
[182]
filter
[183]
The system for preparing the ester-based composition of the present invention comprises a filtration unit for removing solid impurities remaining in at least one of a reaction mixture, a first crude product mixture, a second crude product mixture, an organic layer stream, an ester-rich stream, and a product stream. may include more.
[184]
When a solid catalyst is used, when solid impurities are present in the reaction raw material, or when solid impurities are generated in the course of the reaction, it is necessary to remove impurities to improve the quality of the final product. Accordingly, the present invention may further include a filtration unit for removing solid impurities in the stream.
[185]
The stream to be filtered by the filter unit is not particularly limited, and the filter unit may be applied to all streams moving between each component in the manufacturing system of the present invention. More specifically, in the system for preparing an ester-based composition of the present invention, the filtration section is at least one stream selected from a reaction mixture, a first crude product mixture, a second crude product mixture, an organic layer stream, an ester-rich stream, and a product stream. can be applied to
[186]
The position of the filtration unit varies depending on the stream to be filtered, and the type or type of the filtration unit is not particularly limited as long as it can sufficiently remove solid impurities without loss of an ester compound in the stream. For example, a filtration unit in the form of a filter may be applied.
[187]
[188]
Method for producing an ester-based composition
[189]
The present invention provides a method for producing an ester-based composition that can be implemented by the above-described system for producing an ester-based composition.
[190]
Specifically, the method for preparing the ester-based composition provided by the present invention comprises the steps of forming a reaction mixture containing a polycarboxylic acid and a first alcohol (S1), and subjecting the reaction mixture to an esterification reaction to include the first ester compound. 1 preparing a crude product mixture (S2), trans-esterifying the first crude product mixture and a second alcohol to prepare a second crude product mixture including a second ester compound (S3) ), neutralizing and water separation of the second crude product mixture to obtain an aqueous layer stream and an organic layer stream (S4), distilling the organic layer stream to obtain an alcohol rich stream and an ester rich stream (S5) and the ester rich stream and removing the first alcohol and the second alcohol remaining in the stream to obtain a mixed alcohol stream and a product stream (S6).
[191]
[192]
mixing step (S1)
[193]
Step S1 is performed in the mixing part of the manufacturing system of the present invention, and the polycarboxylic acid corresponding to the reaction raw material and the first alcohol are mixed. The specific method of the mixing is not particularly limited, and considering that the polycarboxylic acid and the first alcohol react in a liquid state, the mixing may be performed through a stirrer or a mixer. Agitation speed, intensity, and time at the time of mixing may vary depending on the flow rate or characteristics of the reaction raw material, and those skilled in the art can perform mixing by selecting an appropriate stirring speed, intensity, and time.
[194]
[195]
Esterification step (S2) and transesterification step (S3)
[196]
In step S2, the esterification reaction between the first alcohol and the polycarboxylic acid in the reaction mixture is performed, and in step S3, the trans-esterification reaction between the first ester compound and the second alcohol in the first crude product mixture is performed. is a step to be
[197]
[198]
Specific reaction conditions in steps S2 and S3 are not particularly limited, and may be carried out under the known temperature and pressure conditions in which the esterification reaction and the trans-esterification reaction are performed, respectively. In addition, at least one of steps S2 and S3 may be performed in the presence of a catalyst.
[199]
When a catalyst is used, it has the advantage that the reaction can be completed faster, and the catalyst is added directly to the reaction mixture and/or the first crude product mixture, or is added to the reaction unit and/or trans reaction unit in which each reaction is performed can be It is slightly more preferable in terms of overall efficiency of the process to add the catalyst directly to the reaction mixture and/or the first crude product mixture.
[200]
[201]
The catalyst is an acid catalyst such as sulfuric acid, hydrochloric acid, phosphoric acid, nitric acid, para-toluenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, propanesulfonic acid, butanesulfonic acid, alkyl sulfuric acid, aluminum lactate, lithium fluoride, potassium chloride, cesium chloride, calcium chloride, iron chloride, phosphoric acid It may be at least one selected from metal salts such as aluminum, metal oxides such as heteropolyacids, natural/synthetic zeolites, cation and anion exchange resins, tetraalkyl titanate and organometallics such as polymers thereof, preferably tetra It may be an alkyl titanate. As the tetraalkyl titanate, TiPT, TnBT, TEHT, etc. can be used, and it is preferable to use a tetraalkyl titanate having the same alkyl group as the alkyl group of the alcohol to be reacted as a ligand. For example, for the reaction between propanol and terephthalic acid, it is preferred to use tetrapropyl titanate. As such, when a catalyst having the same alkyl group as an alcohol as a ligand is used, catalyst by-products that may be generated in a subsequent process are not generated, or even if generated, it is preferable because it can be easily controlled.
[202]
The amount of the catalyst used may vary depending on the type of catalyst, for example, in the case of a homogeneous catalyst, 0.001 to 5% by weight, 0.001 to 4% by weight, 0.01 to 3% by weight of the total amount of the reaction mixture or the first crude product mixture, or within the range of 0.01 to 2 wt%, and in the case of a heterogeneous catalyst in the range of 5 to 200 wt%, 5 to 150 wt%, 10 to 150 wt%, or 20 to 150 wt% of the total amount of the reaction mixture or first crude product mixture can tomorrow
[203]
[204]
The step S2 may be performed differently depending on the type of the reactor described above. For example, the step S2 is performed in N reactors connected in series, and each reactor satisfies the following formulas 1) and 2), wherein N is 2 It can be an integer of more than:
[205]
1) T n1-1 ≤T n1
[206]
2) E n2-1 ≥E n2 ≥E 1
[207]
In the formula, n1 is an integer from 2 to N, n2 is an integer from 3 to N,
[208]
T x = temperature of the xth reactor
[209]
E x = {(the number of moles of alcohol input to the x-th reactor - c* the number of moles of dicarboxylic acid input to the x-th reactor/ c* the number of moles of dicarboxylic acid input to the first reactor) * 100%},
[210]
In the T x and E x , x is an integer of 1 to N,
[211]
Where c is the number of carboxylic acid groups included in one molecule of polycarboxylic acid.
[212]
[213]
As another example, step S2 is performed in N reactors connected in parallel, and the formation of the first crude product mixture in each reactor is semi-continuous over N reactors, wherein N is 2 It may be an integer of more than one.
[214]
[215]
A case in which step S2 is performed by the two methods described above has been specifically described in the manufacturing system section above, and detailed description thereof will be omitted.
[216]
[217]
Neutralization step (S4)
[218]
In step S4, the acid catalyst remaining in the second crude product mixture is neutralized and separated with water to form an organic layer stream containing an ester compound as a final product and an aqueous layer stream containing impurities.
[219]
When the catalyst remains in the final product, the ester-based composition, a problem of deterioration of quality occurs, and accordingly, it is necessary to neutralize and remove the catalyst in the second crude product mixture.
[220]
As the neutralizing agent, an aqueous base solution having a base concentration of 0.1 to 50% by weight may be used, for example, sodium hydroxide or sodium hydrogen carbonate aqueous solution may be used.
[221]
The specific execution of the step S4 has been described in detail in the manufacturing system section above, and the detailed description will be omitted.
[222]
[223]
Distillation step (S5) and product purification step (S6)
[224]
Steps S5 and S6 are steps performed to remove alcohol remaining in the organic layer stream that has undergone neutralization and water separation. In the previous neutralization step, the water layer and the organic layer are separated, but since alcohol has an affinity for both water and ester, a part of the alcohol is present in the organic layer together with esterification. Therefore, in order to further improve the quality of the final product, it is necessary to remove the alcohol in the organic layer. First, an ester-rich stream is obtained through distillation, and secondly, the first alcohol and the second alcohol in the ester-rich stream are separated. Remove.
[225]
The specific execution of the steps S5 and S6 has been described in detail in the manufacturing system section above, and detailed description will be omitted.
[226]
[227]
The method for preparing the ester-based composition of the present invention may further include an alcohol recovery step (S7) and a wastewater treatment step (S8) in addition to the steps described above.
[228]
[229]
Alcohol recovery step (S7)
[230]
In the method for producing the ester-based composition of the present invention, step S7, which may be further included, comprises mixing the alcohol-rich stream obtained in step S5 and the mixed alcohol stream obtained in step S6 to form a first recovered alcohol stream, and separating the first recovered alcohol stream into a water stream, a first alcohol stream and a second alcohol stream to form a water stream, a first alcohol stream and a second alcohol stream (S7).
[231]
[232]
Since the first alcohol and the second alcohol removed in the previous distillation and purification steps correspond to the reaction raw materials, if they are properly treated and used again as a reaction raw material, the economic feasibility and efficiency of the overall process can be improved. To this end, in step S7, the alcohol-rich stream obtained in step S5 and the mixed alcohol stream obtained in step S6 are recovered and mixed to form a first recovered alcohol stream, which is separated into water, a first alcohol, and a second alcohol to be reused. . The separation in this step may be performed in a mixed alcohol separation column in the above-described production system.
[233]
[234]
Specifically, the first alcohol stream obtained in this step may be used as the first alcohol in step S1, and the second alcohol stream obtained in this step may be used as the second alcohol in step S2. In addition, the alcohol having a large carbon number among the first alcohol and the second alcohol, that is, a higher alcohol may be transferred to a wastewater treatment unit to be used as an additive in a wastewater treatment step to be described later. Specific details in which this step is performed other than that have been specifically described in the manufacturing system section above, and detailed descriptions are omitted.
[235]
[236]
Wastewater treatment step (S8)
[237]
In the method for producing the ester-based composition of the present invention, the step that may be further included together with step S7 is to mix the water stream obtained in step S4 with the water stream obtained in step S7 to form a preliminary wastewater stream, It may be a step (S8) of adding an alcohol having a greater carbon number among the first alcohol and the second alcohol to the preliminary wastewater stream to form a second recovered alcohol stream including the first alcohol and the second alcohol and a wastewater stream.
[238]
A large amount of water is obtained in the preceding neutralization step and alcohol recovery step, but the lower alcohol having a small carbon number among the first alcohol and the second alcohol has high solubility in water and may be dissolved in the large amount of water. In general, the large amount of water should be immediately discharged and treated as wastewater. However, if the alcohol content in the wastewater is high, it may cause environmental problems, so it is necessary to reduce the alcohol content in the wastewater by treating it in advance. For this purpose, this step S8 may be applied.
[239]
In this step, the water stream obtained in step S4 and the water stream obtained in step S7 are mixed to form a preliminary wastewater stream, and a higher alcohol having a larger carbon number among the first alcohol and the second alcohol is added to the preliminary wastewater stream as an additive. Alcohol having a small number of carbon atoms has high solubility in water, but since it has high solubility in higher alcohols having a large number of carbon atoms, it can be separated from water and dissolved as the additive, and since the additive has a large number of carbon atoms, it does not mix well with water. It can form a layer separate from water. Therefore, it is possible to separate the mixed alcohol layer and the wastewater layer by simple layer separation.
[240]
The reason for using the higher alcohol among the first alcohol and the second alcohol corresponding to the reaction raw material instead of the other organic solvent as the additive is that most of the organic layer components obtained when the first alcohol or the second alcohol is used as the additive is the first alcohol and a second alcohol, and this mixed alcohol can be separated together because it has the same components as the mixed alcohol obtained in another step. If a separate organic solvent is used as an additive, there may be a problem that an additional means for treating the alcohol mixed in the organic solvent is required.
[241]
The amount of the additive added in this step is not particularly limited, but since the concentration of alcohol in the preliminary wastewater stream is not very high, it may be used in a small amount compared to the preliminary wastewater stream. The specific amount of the additive may vary, such as the type of the first alcohol and the second alcohol, the flow rate of the preliminary wastewater stream, and the like, and a person skilled in the art can perform this step by selecting an appropriate amount of the additive. Specific details in which this step is performed other than that have been specifically described in the manufacturing system section above, and detailed descriptions are omitted.
[242]
[243]
In addition to the above steps, according to an embodiment of the present invention, the production method of the present invention may further include the step of passing the stream through a filter to remove solid impurities.
[244]
The filtration step may be performed on the stream between each step. For the filtration, methods known in the art may be applied without particular limitation, and filtration may be performed using filters of various materials.
[245]
[246]
In the method for producing the ester-based composition of the present invention, the carbon number of the first alcohol may be greater than the carbon number of the second alcohol. In the case of using the production method of the present invention, since the trans-esterification reaction proceeds after the esterification reaction, it is preferable to first esterify an alcohol having a large carbon number and then trans-esterify the alcohol having a small carbon number. When the reaction is performed in this order, the trans-esterification reaction at the subsequent stage is easy, and the content of each ester in the ester-based composition, which is the final product, can be smoothly controlled.
[247]
[248]
In the method for preparing the ester-based composition of the present invention, the steps S1 to S6 may be performed continuously, and even when the steps S7 and/or S8 are included, the entire manufacturing method may be continuously performed. As described above in the manufacturing system, all components constituting the manufacturing system of the present invention may be continuously operated, and accordingly, all steps may also be continuously performed.
[249]
[250]
Explanation of symbols
[251]
1: mixing part
[252]
11: first alcohol
[253]
12: polycarboxylic acid
[254]
13: reaction mixture
[255]
2: reaction part
[256]
21: first crude product mixture
[257]
3: Trans reaction part
[258]
31: second alcohol
[259]
32: second crude product mixture
[260]
4: Chinese Department
[261]
41: organic layer stream
[262]
42: water stream
[263]
5: distillation unit
[264]
51: Ester Rich Stream
[265]
52: alcohol rich stream
[266]
6: Product refining unit
[267]
61: product stream
[268]
62: mixed alcohol stream
[269]
7: Mixed alcohol tank
[270]
8: Mixed Alcohol Separation Column
[271]
81: first alcohol stream
[272]
82: second alcohol stream
[273]
83: water stream
[274]
9: Wastewater treatment department
[275]
91: higher alcohol among the first alcohol and the second alcohol
[276]
92: second recovered alcohol stream
[277]
93: wastewater stream
Claims
[Claim 1]
a mixing unit in which a reaction mixture of the polycarboxylic acid and the first alcohol is formed; a reaction unit in which an esterification reaction of the reaction mixture is performed to form a first crude product mixture including a first ester compound; a trans reaction unit in which a trans-esterification reaction is performed between the first crude product mixture formed in the reaction unit and a second alcohol separately introduced to form a second crude product mixture containing a second ester compound; a neutralization unit in which neutralization and separation of the second crude product mixture are performed to form an aqueous layer stream and an organic layer stream; a distillation unit for distilling the organic layer stream to form an alcohol-rich stream and an ester-rich stream; and a product refining unit for removing the first and second alcohols remaining in the ester-rich stream to form a mixed alcohol stream and a product stream comprising the first alcohol and the second alcohol; .
[Claim 2]
The system for producing an ester-based composition according to claim 1, further comprising a mixed alcohol tank for receiving and storing the alcohol-rich stream formed in the distillation unit and the mixed alcohol stream formed in the product refining unit.
[Claim 3]
2. The method of claim 1, wherein the alcohol-rich stream formed in the distillation unit and the mixed alcohol stream formed in the product refining unit are sent to form a first recovered alcohol stream, wherein the first recovered alcohol stream is combined with a water stream and a first alcohol stream. and a mixed alcohol separation column for separating into a second alcohol stream.
[Claim 4]
The preliminary wastewater according to claim 3, wherein the water stream of the neutralization unit and the water stream separated in the mixed alcohol separation column are transferred to form a preliminary wastewater stream, and an alcohol having a greater carbon number among the first alcohol and the second alcohol is used as the preliminary wastewater. and a wastewater treatment unit added to the stream to form a wastewater stream and a second recovered alcohol stream comprising the first alcohol and the second alcohol.
[Claim 5]
5. The system of claim 4, wherein the second recovered alcohol stream is transferred to and recovered from the mixed alcohol separation column.
[Claim 6]
The method according to claim 1, wherein the reaction unit includes N reactors and a variable control unit connected in series of the first to Nth reactors, and the variable control unit controls the temperature of each reactor and each reactor so that the following Equations 1) and 2) are satisfied. intended to control the amount of alcohol, where N is an integer of 2 or more ester-based composition is fed to the manufacturing system: 1) T n1-1 ≤T n1 2) E n2-1 ≥E n2 ≥E 1 expression in, n1 is is an integer of 2 to N, n2 is an integer of 3 to N, T x = temperature of the xth reactor E x = {(number of moles of alcohol input to the xth reactor - c*polycarboxylic acid injected into the xth reactor of moles/c*number of moles of polycarboxylic acid input to the first reactor)*100%} In T x and E x , x is an integer from 1 to N, and c is a carboxylic acid group contained in one molecule of polycarboxylic acid. is the number of
[Claim 7]
The method according to claim 1, wherein the reaction unit comprises N reactors connected in parallel of the first reactor to the Nth reactor and a feed control unit, wherein the feed control unit is configured such that the formation of the first crude product mixture in each reactor is directed to the N reactors. It is to control the input amount and the input route of the reaction mixture input from the mixing unit to the reaction unit so as to be carried out semi-continuously throughout, wherein N is an integer of 2 or more.
[Claim 8]
The system for preparing an ester-based composition according to claim 1, further comprising a catalyst input unit for introducing a catalyst into the reaction mixture or the first crude product mixture.
[Claim 9]
The method of claim 1, wherein the neutralization unit includes one or more neutralizers, and the inner space of the neutralizer has one or more partition walls such that the neutralization space and the layer separation space are respectively divided in the left and right directions to form a passage connecting the two spaces. The system for producing an ester-based composition is provided, wherein the passage starts from the upper portion of the neutralization space.
[Claim 10]
The method of claim 1 , further comprising a filter for removing solid impurities remaining in at least one of the reaction mixture, the first crude product mixture, the second crude product mixture, the organic layer stream, the ester rich stream and the product stream. A system for the preparation of a phosphorus ester-based composition.
[Claim 11]
The system for producing an ester-based composition according to claim 1, wherein the production system for the ester-based composition is operated continuously.
[Claim 12]
The system of claim 1, wherein the polycarboxylic acid is at least one selected from the group consisting of dicarboxylic acid, tricarboxylic acid, and tetracarboxylic acid.
[Claim 13]
The method according to claim 12, wherein the dicarboxylic acid is at least one selected from the group consisting of linear dicarboxylic acids having 2 to 10 carbon atoms, terephthalic acid, phthalic acid, isophthalic acid, cyclohexane dicarboxylic acid, anhydrides thereof, and derivatives thereof, The tricarboxylic acid is at least one selected from the group consisting of citric acid, trimellitate acid, cyclohexane tricarboxylic acid, anhydrides thereof, and derivatives thereof, and the tetracarboxylic acid is benzenetetracarboxylic acid, furantetracarboxylic acid, cyclohexane tetra A system for producing at least one ester-based composition selected from the group consisting of carboxylic acid, tetrahydrofuran, tetracarboxylic acid, anhydrides thereof, and derivatives thereof.
[Claim 14]
Forming a reaction mixture comprising a polycarboxylic acid and a first alcohol (S1); preparing a first crude product mixture including a first ester compound by subjecting the reaction mixture to an esterification reaction (S2); preparing a second crude product mixture including a second ester compound by trans-esterifying the first crude product mixture and a second alcohol (S3); neutralizing and water separation of the second crude product mixture to obtain an aqueous layer stream and an organic layer stream (S4); distilling the organic layer stream to obtain an alcohol-rich stream and an ester-rich stream (S5); and removing the first alcohol and the second alcohol remaining in the ester-rich stream to obtain a mixed alcohol stream and a product stream (S6).
[Claim 15]
15. The method of claim 14, wherein the alcohol-rich stream obtained in step S5 and the mixed alcohol stream obtained in step S6 are mixed to form a first recovered alcohol stream, and wherein the first recovered alcohol stream is combined with a water stream, a first alcohol stream and Separating into a second alcohol stream to form a water stream, a first alcohol stream, and a second alcohol stream (S7);
[Claim 16]
The ester-based composition of claim 15, wherein the first alcohol stream obtained in step S7 is used as the first alcohol in step S1, and the second alcohol stream obtained in step S7 is used as the second alcohol in step S2. manufacturing method.
[Claim 17]
16. The method according to claim 15, wherein the water stream obtained in step S4 and the water stream obtained in step S7 are mixed to form a preliminary wastewater stream, and an alcohol having a greater carbon number among the first alcohol and the second alcohol in the preliminary wastewater stream. Forming a second recovered alcohol stream and a wastewater stream including the first alcohol and the second alcohol by adding (S8); Method for producing an ester-based composition further comprising.
[Claim 18]
15. The method according to claim 14, wherein the step S2 is performed in N reactors connected in series, each reactor satisfies the following formulas 1) and 2), wherein N is an integer of 2 or more: 1) T n1 -1 ≤T n1 2) E n2-1 ≥E n2 ≥E 1 in formula, n1 is an integer from 2 to N, n2 is an integer from 3 to N, T x = x the temperature of reactor E x = { (the number of moles of alcohol injected into the x-th reactor - c* the number of moles of dicarboxylic acid injected into the x-th reactor/c* the number of moles of dicarboxylic acid injected into the first reactor) * 100%}, wherein the T x and E In x , x is an integer of 1 to N, and c is the number of carboxylic acid groups included in one molecule of polycarboxylic acid.
[Claim 19]
15. The method of claim 14, wherein step S2 is performed in N reactors connected in parallel, and the formation of the first crude product mixture in each reactor is performed semi-continuous over the N reactors, wherein N is an integer of 2 or more. Method for producing an ester-based composition.
[Claim 20]
15. The method of claim 14, wherein at least one of steps S2 and S3 is performed in the presence of a catalyst, wherein the catalyst is a tetraalkyl titanate.
[Claim 21]
The method of claim 14, wherein the carbon number of the first alcohol is greater than the carbon number of the second alcohol.
[Claim 22]
15. The method of claim 14, wherein the steps S1 to S6 are continuously performed.