DESC:FIELD
The present disclosure relates to alkyl ketoximes.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
Methyl isobutyl ketoxime (MIBKO) is an alkyl ketoxime used primarily as an anti-skinning agent in paints, coatings, and printing inks. MIBKO is particularly useful for its ability to inhibit the skinning (formation of a skin or film) that can occur when oxygen reacts with certain coatings or inks when exposed to air. MIBKO is added to formulations to prevent the undesirable formation of a skin on the surface of the liquid product during storage or when the container is opened and closed. MIBKO helps to maintain the quality and usability of the product by inhibiting the skinning process. MIBKO also find applications in the preparation of silanes such as methyltris(MIBKO)silane, vinyltri(MIBKO)silane and tetrakis(MIBKO)silane, and the like, which are primarily used as a crosslinker in adhesives and sealants, as a coupling agent in paint and rubber; and as a compatibilizer in plastics.
Methyl isobutyl ketoxime (MIBKO) is commonly synthesized using conventional methods in the chemical industry. Conventional methods require pure reactants and may lead to the formation of undesired by-products or impurities. These impurities can affect the purity and quality of the final MIBKO product. Due to the necessity of pure reactants, these processes are not economically feasible. Further, in conventional methods, it is difficult to achieve high selectivity for the desired product. Furthermore, the conventional methods are associated with various drawbacks such as side reactions or formation of multiple products thereby leading to a less efficient synthesis.
Therefore, there is felt a need to provide an improved process for the preparation of methyl isobutyl ketoxime that obviates the drawbacks mentioned hereinabove or at least provides a useful alternative.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
An object of the present disclosure is to ameliorate one or more problems of the background or to at least provide a useful alternative.
Another object of the present disclosure is to provide a process for the preparation of methyl isobutyl ketoxime (MIBKO).
Yet another object of the present disclosure is to provide a process for the preparation of methyl isobutyl ketoxime (MIBKO) with high yield and high purity.
Still another object of the present disclosure is to provide a process for the preparation of methyl isobutyl ketoxime (MIBKO) which is simple and efficient.
Yet another object of the present disclosure is to provide a process for the preparation of methyl isobutyl ketoxime (MIBKO) which is cost-effective and environment friendly.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure relates to a process for the preparation of methyl isobutyl ketoxime (MIBKO), the process comprises the following steps:
a. reacting methyl isobutyl ketone with a crude hydroxylamine sulphate solution under stirring at a first predetermined temperature and at a predetermined pH for a first predetermined time period to obtain a reaction mixture;
b. neutralizing the reaction mixture with a neutralizing agent and heating to a second predetermined temperature for a second predetermined time period followed by cooling to a temperature in the range of 20 °C to 40 °C to obtain a biphasic mixture containing an aqueous layer and an organic layer comprising methyl isobutyl ketoxime; and
c. separating the organic layer comprising methyl isobutyl ketoxime from the biphasic mixture followed by distilling the organic layer to obtain the methyl isobutyl ketoxime.
In an embodiment of the present disclosure, the crude hydroxylamine sulphate solution comprises
• hydroxylamine sulphate in an amount in the range of 10 mass% to 25 mass%;
• ammonium sulphate in an amount in the range of 1 mass% to 10 mass%; and
• sulphuric acid in an amount in the range of 1 mass% to 11 mass%;
wherein the mass% of each ingredient is with respect to the total mass of the crude hydroxylamine sulphate solution.
In an embodiment of the present disclosure, the first predetermined temperature is in the range of 20 °C to 40 °C.
In an embodiment of the present disclosure, the second predetermined temperature is in the range of 75 °C to 85 °C.
In an embodiment of the present disclosure, the predetermined pH is in the range of 8.5 to 8.8.
In an embodiment of the present disclosure, the first predetermined time period is in the range of 10 minutes to 15 minutes.
In an embodiment of the present disclosure, the second predetermined time period is in the range of 30 minutes to 90 minutes.
In an embodiment of the present disclosure, the neutralizing agent is ammonium hydroxide.
In an embodiment of the present disclosure, the methyl isobutyl ketoxime is characterized by having a purity of 99.5%, APHA (American Public Health Association) value of less than 5, and a refractive index in the range of 1.4440 to 1.4443.
In an embodiment of the present disclosure, the yield of methyl isobutyl ketoxime is more than 95%.
In an embodiment of the present disclosure, a mole ratio of methyl isobutyl ketone to hydroxylamine sulphate is in the range of 1:1 to 1:1.15.
In an embodiment of the present disclosure, a by-product in the aqueous layer is ammonium sulphate.
In an embodiment of the present disclosure, the ammonium sulphate is characterized by having a minimum ammonical nitrogen of 20.5 mass%, minimum sulphate content of 23 mass%, maximum free acidity of 0.025 mass%, and maximum moisture content of 1 mass%.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
The present disclosure will now be described with the help of the accompanying drawing, in which:
Figure 1 illustrates a graphical representation showing the effect of temperature at which the reaction is carried out, on the yield of the methyl isobutyl ketoxime (MIBKO); and
Figure 2 illustrates a graphical representation of the effect of pH at which the reaction is carried out, on the yield of the methyl isobutyl ketoxime (MIBKO).
DETAILED DESCRIPTION
The present disclosure relates to alkyl ketoximes. Particularly, the present disclosure relates to a process for the preparation of Methyl isobutyl ketoxime (MIBKO).
Embodiments of the present disclosure will now be described with reference to the accompanying drawings.
Embodiments, of the present disclosure, will now be described herein. Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known methods, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and method of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.
As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed elements.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
Methyl isobutyl ketoxime (MIBKO) synthesis often relies on conventional methods that demand pure reactants, leading to costly and less efficient processes. These methods also struggle with high selectivity and are prone to side reactions, making them economically unfeasible.
The present disclosure provides a process for the preparation of methyl isobutyl ketoxime.
The process comprises the following steps:
a. reacting methyl isobutyl ketone with a crude hydroxylamine sulphate solution under stirring at a first predetermined temperature and at a predetermined pH for a first predetermined time period to obtain a reaction mixture;
b. neutralizing the reaction mixture with a neutralizing agent and heating to a second predetermined temperature for a second predetermined time period followed by cooling to a temperature in the range of 20 °C to 40 °C to obtain a biphasic mixture containing an aqueous layer and an organic layer comprising methyl isobutyl ketoxime; and
c. separating the organic layer comprising methyl isobutyl ketoxime from the biphasic mixture followed by distilling the organic layer to obtain the methyl isobutyl ketoxime.
The process is described in detail.
In a first step, methyl isobutyl ketone is reacted with a crude hydroxylamine sulphate solution under stirring at a first predetermined temperature and at a predetermined pH for a first predetermined time period to obtain a reaction mixture.
In an embodiment of the present disclosure, the crude hydroxylamine sulphate solution comprises hydroxylamine sulphate in an amount in the range of 10 mass% to 25 mass% with respect to the total mass of the crude hydroxylamine sulphate solution, ammonium sulphate in an amount in the range of 1 mass% to 10 mass% with respect to the total mass of the crude hydroxylamine sulphate solution, and sulphuric acid in an amount in the range of 1 mass% to 11 mass% with respect to the total mass of the crude hydroxylamine sulphate solution.
In another embodiment of the present disclosure, the crude hydroxylamine sulphate solution comprises hydroxylamine sulphate in an amount in the range of 23 mass% to 25 mass% with respect to the total mass of the crude hydroxylamine sulphate solution, ammonium sulphate in an amount in the range of 1 mass% to 5 mass% with respect to the total mass of the crude hydroxylamine sulphate solution, and sulphuric acid in an amount in the range of 1 mass% to 5 mass% with respect to the total mass of the crude hydroxylamine sulphate solution.
In an embodiment of the present disclosure, the process utilizes the crude Hydroxylamine sulphate solution is obtained by the Raschig process which is generally used for the production of caprolactam.
In an embodiment of the present disclosure, a mole ratio of methyl isobutyl ketone to hydroxylamine sulphate is in the range of 1:1 to 1:1.15. In an exemplary embodiment, the mole ratio of methyl isobutyl ketone to the hydroxylamine sulphate is 1:1.05.
The hydroxylamine sulphate solution utilized in the process of the present disclosure comprises approximately 25 mass% hydroxylamine sulphate. The crude hydroxylamine solution also comprises ammonium sulphate, sulfuric acid, and water. In the reaction with methyl isobutyl ketone to produce MIBKO, only hydroxylamine sulphate participates, while the remaining constituents are neutralized by ammonium hydroxide, forming ammonium sulphate. Consequently, the mole ratio of MIBK to hydroxylamine sulphate should be maintained between 1:1 and 1:1.15. A lower mole ratio decreases product yield, while a ratio exceeding this range leads to unnecessary wastage of reactants.
In an embodiment of the present disclosure, the first predetermined temperature is in the range of 20 °C to 40 °C. In an exemplary embodiment, the first predetermined temperature is 25 °C.
In an embodiment of the present disclosure, the predetermined pH is in the range of 8.5 to 8.8. In an exemplary embodiment, the predetermined pH is 8.6. In another exemplary embodiment, the predetermined pH is 8.8.
In an embodiment of the present disclosure, the first predetermined time period is in the range of 10 minutes to 15 minutes. In an exemplary embodiment, the first predetermined time period is 12 minutes.
In a second step, the reaction mixture is neutralized with a neutralizing agent and heated to a second predetermined temperature for a second predetermined time period followed by cooling to a temperature in the range of 20 °C to 40 °C to obtain a biphasic mixture containing an aqueous layer and an organic layer comprising methyl isobutyl ketoxime.
In an embodiment of the present disclosure, the neutralizing agent is ammonium hydroxide. In an exemplary embodiment, the neutralizing agent is 25 % ammonium hydroxide solution.
In an embodiment of the present disclosure, the second predetermined temperature is in the range of 75 °C to 85 °C. In an exemplary embodiment, the second predetermined temperature is 83 °C.
In an embodiment of the present disclosure, the second predetermined time period is in the range of 30 minutes to 90 minutes. In an exemplary embodiment, the second predetermined time period is 60 minutes.
In an exemplary embodiment, the cooling is carried out at 25 °C.
In an embodiment of the present disclosure, a by-product in the aqueous phase is ammonium sulphate.
In an embodiment of the present disclosure, the ammonium sulphate is characterized by having a minimum ammonical nitrogen content of 20.5 mass%, minimum sulphate content of 23 mass%, maximum free acidity of 0.025 mass%, and maximum moisture content of 1 mass%.
In a third step, the organic layer comprising the methyl isobutyl ketoxime is separated from the biphasic mixture followed by distilling the organic layer to obtain the methyl isobutyl ketoxime.
In an embodiment of the present disclosure, the methyl isobutyl ketoxime is characterized by having a purity of 99.5%, APHA (American Public Health Association) value of less than 5, and a refractive index in the range of 1.4440 to 1.4443.
In an embodiment of the present disclosure, the yield of methyl isobutyl ketoxime is more than 95%. In an exemplary embodiment, the yield of methyl isobutyl ketoxime is 95.05%.
One of the primary advantage of the process of the present disclosure for synthesizing Methyl isobutyl ketoxime (MIBKO) is that it does not require highly purified reactants. Traditionally, many chemical syntheses rely on the use of highly pure starting materials to ensure consistent product quality and yield. However, obtaining such high-purity reactants often involves multiple stages of purification, such as distillation, crystallization, or filtration, all of which significantly increase production costs. These costs arise not only from the additional equipment and energy required for purification but also from the waste management of by-products or impurities removed during these steps. In contrast, the process of the present disclosure circumvents these requirements, allowing the use of commercially available, less purified reactants. Additionally, the ability to use impure reactants can increase the flexibility of the production process, allowing manufacturers to source cheaper, more readily available materials.
Further, reducing the need for pure reactants decreases the overall waste generated by the process, leading to a more sustainable and environmentally friendly production method. This not only helps in cutting costs associated with waste management but also aligns with the increasing regulatory and consumer demand for greener processes.
The aqueous layer, which is a by-product, is utilized to prepare fertilizer grade ammonium sulphate with desired ammonical nitrogen, sulphate content, free acidity and moisture content.
The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment but are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
The present disclosure is further described in light of the following experiments which are set forth for illustration purpose only and not to be construed for limiting the scope of the disclosure. The following experiments are scalable to industrial/commercial method.
EXPERIMENTAL DETAILS
EXPERIMENT 1: A process for the preparation of methyl isobutyl ketoxime (MIBKO) in accordance with the present disclosure
¬¬¬¬¬¬¬¬¬¬Example 1
125 mL of methyl isobutyl ketone (MIBK, Density 0.802 g/cc) was reacted with 291.6 mL of crude hydroxylamine sulphate solution (having 25% concentration of hydroxylamine sulphate (HAS) content and Density – 1.18 g/cc) under stirring at 120 rpm at 25 °C and at 8.6 pH for 12 minutes to obtain a reaction mixture. The reaction mixture was neutralized with 109 mL of 25% ammonium hydroxide solution and heated to 83 °C and the temperature was maintained for 60 minutes followed by cooling to 25 °C to obtain a biphasic mixture comprising an aqueous layer and an organic layer comprising the methyl isobutyl ketoxime. The organic layer was separated from the biphasic mixture followed by distilling the organic layer to obtain the methyl isobutyl ketoxime (MIBKO).
The so obtained MIBKO has a purity of more than 99.5%, APHA value of less than 5 and refractive index of 1.4440. The obtained yield was 95.05%.
Examples 2 and 3
Examples 2 and 3 were carried out in a similar manner, except by varying the reaction temperature to 63 °C and 43 °C for Example 2 and Example 3 respectively. The effect of varying temperature is illustrated in Figure 1. From Figure 1 it is clear that on increasing the temperature from 43 °C to 63 °C, the percentage yield increased. On further increasing the temperature to 83 °C, the yield increased up to 95%. This was due to enhanced reactivity between MIBK and Hydroxylamine to prepare MIBKO.
Examples 4 to 7
Examples 4, 5, 6, and 7 were carried out in a similar manner except by varying the reaction pH to 7.2, 7.5, 8.1 and 8.8 for Example 4, Example 5, Example 6 and Example 7 respectively. The effect of varying pH is illustrated in Figure 2. From Figure 2 it is observed that when the reaction was carried out at 7.2 pH the percentage yield was 84.22%. On increasing the pH to 7.5 the yield increased to 87.3%. On further increasing the pH to 8.1 the yield further increased to 91.89%. The maximum yield was obtained at pH 8.6 (Example 1). This increase in yield was due to the complete neutralization of the free sulphuric acid liberated from Hydroxylamine sulphate solution at this pH. On further increasing the pH to 8.8, the yield slightly decreased. However, the pH range studied had no noticeable impact on the quality of the methyl isobutyl ketoxime obtained.
From the above examples, it is clear that by carefully selecting the reaction temperature and the reaction pH, a high yield of methyl isobutyl ketoxime can be obtained from the crude hydroxylamine sulphate solution. The process of the present disclosure provides a high yield of methyl isobutyl ketoxime without the use of pure chemicals, thus making the process of the present disclosure economical. Additionally, the process of the present disclosure minimizes the formation of undesired by-products and impurities, further enhancing the overall efficiency and quality of the final product. The ability to use less pure reactants not only reduces production costs but also aligns with sustainable and environmental friendly practices, meeting the growing demand for green chemistry solutions.
Furthermore, the ammonium sulphate obtained as a by-product can be utilized as a fertilizer. This further adds to the economic and environmental benefit of the process. This not only prevents waste but also supports sustainable agriculture by improving soil quality. It reduces the need for synthetic fertilizers, which are often costly and harmful to the environment. By turning a by-product into something useful, in this case as a fertilizer, the process helps to create a sustainable system.
TECHNICAL ADVANCEMENT
The present disclosure described hereinabove has several technical advantages including, but not limited to, the realization of
? a process for the preparation of methyl isobutyl ketoxime, that
• is simple, efficient and cost effective;
• does not require the utilization of purified hydroxylamine sulphate crystals or solution;
• produces by-products that can be used as fertilizers; and
• produces high purity (99.5%) methyl isobutyl ketoxime (MIBKO) with APHA value less than 5.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the invention to achieve one or more of the desired objects or results. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Variations or modifications to the formulation of this invention, within the scope of the invention, may occur to those skilled in the art upon reviewing the disclosure herein. Such variations or modifications are well within the spirit of this invention.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values given for various physical parameters, dimensions, and quantities are only approximate values and it is envisaged that the values higher than the numerical value assigned to the physical parameters, dimensions, and quantities fall within the scope of the invention unless there is a statement in the specification to the contrary.
While considerable emphasis has been placed herein on the specific features of the preferred embodiment, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiment without departing from the principles of the disclosure. These and other changes in the preferred embodiment of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation. ,CLAIMS:WE CLAIM:
1. A process for the preparation of methyl isobutyl ketoxime (MIBKO), said process comprising the following steps:
a. reacting methyl isobutyl ketone with a crude hydroxylamine sulphate solution under stirring at a first predetermined temperature and at a predetermined pH for a first predetermined time period to obtain a reaction mixture;
b. neutralizing said reaction mixture with a neutralizing agent and heating to a second predetermined temperature for a second predetermined time period followed by cooling to a temperature in the range of 20 °C to 40 °C to obtain a biphasic mixture containing an aqueous layer and an organic layer comprising methyl isobutyl ketoxime; and
c. separating said organic layer comprising methyl isobutyl ketoxime from said biphasic mixture followed by distilling said organic layer to obtain said methyl isobutyl ketoxime.
2. The process as claimed in claim 1, wherein said crude hydroxylamine sulphate solution comprises:
• hydroxylamine sulphate in an amount in the range of 10 mass% to 25 mass%;
• ammonium sulphate in an amount in the range of 1 mass% to 10 mass%; and
• sulphuric acid in an amount in the range of 1 mass% to 11 mass%,
wherein the mass% of each ingredient is with respect to the total mass of said crude hydroxylamine sulphate solution.
3. The process as claimed in claim 1, wherein said first predetermined temperature is in the range of 20 °C to 40 °C.
4. The process as claimed in claim 1, wherein said second predetermined temperature is in the range of 75°C to 85 °C.
5. The process as claimed in claim 1, wherein said predetermined pH is in the range of 8.5 to 8.8.
6. The process as claimed in claim 1, wherein said first predetermined time period is in the range of 10 minutes to 15 minutes.
7. The process as claimed in claim 1, wherein said second predetermined time period is in the range of 30 minutes to 90 minutes.
8. The process as claimed in claim 1, wherein said neutralizing agent is ammonium hydroxide.
9. The process as claimed in claim 1, wherein the methyl isobutyl ketoxime is characterized by having a purity of 99.5%, APHA (American Public Health Association) value of less than 5, and a refractive index in the range of 1.4440 to 1.4443.
10. The process as claimed in claim 1, wherein the yield of methyl isobutyl ketoxime is more than 95%.
11. The process as claimed in claim 1, wherein a mole ratio of methyl isobutyl ketone to hydroxylamine sulphate is in the range of 1:1 to 1:1.15.
12. The process as claimed in claim 1, wherein a by-product in said aqueous layer is ammonium sulphate.
13. The process as claimed in claim 12, wherein said ammonium sulphate is characterized by having a minimum ammonical nitrogen of 20.5 mass%, a minimum sulphate content of 23 mass%, a maximum free acidity of 0.025 mass%, and a maximum moisture content of 1 mass%.
Dated this 01st day of February, 2025

_______________________________
MOHAN RAJKUMAR DEWAN, IN/PA – 25
of R.K. DEWAN & CO.
Authorized Agent of Applicant

TO,
THE CONTROLLER OF PATENTS
THE PATENT OFFICE, AT MUMBAI