Description:FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENT RULES, 2003

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

Title of invention:
A SYSTEM AND METHOD FOR TREATMENT OF BY-PRODUCTS IN ACRYLAMIDO TERTIARY BUTYL SULFONIC ACID SYNTHESIS

APPLICANT:
VINATI ORGANICS LIMITED
An Indian entity having address at:
Parinee Crescenzo, A Wing, 11th floor, 1102, G Block, Behind MCA, Bandra Kurla Complex, Bandra (east), Mumbai 400051, Maharashtra, India

The following specification describes the invention and the manner in which it is to be performed.

CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY
The present application claims no priority from any of the patent application(s).
TECHNICAL FIELD
The present subject matter described herein, in general, relates to by-product recovery, more particularly relates to a system and method for treatment of by-products in the Acrylamido tertiary butyl sulfonic acid (ATBS) synthesis.
BACKGROUND
Acrylamido tertiary butyl sulfonic acid (ATBS) is used as a modifier for acrylic fiber, a monomer raw material for dispersing agent or coagulating agent, a monomer raw material for thickening agent of cosmetic, or a monomer raw material for production of a chemical used in higher-order recovery of crude oil. ATBS is a white, needle-like crystal at a normal state with a melting point of 185° C. ATBS is ordinarily produced by subjecting reactions of acrylonitrile, sulfuric acid and isobutylene.
However, several by-products such as acrylonitrile (ACRN), 2-methylidene-1,3-propylenedisulfonic acid (IBDSA), 2-methyl-2-propenyl-1-sulfonic acid (IBSA), Acrylamido methyl propane disulfonic acid (AMPDSA), N-Tertiary Butyl Acrylamide (TBA), and unknown organic impurities are formed along with pure ATBS preparation process.
Some of the above-mentioned compounds are classified as carcinogenic, mutagenic or reprotoxic (CMR). In the state of art, the by-products such as acrylonitrile and TBAA are disposed of as industrial waste as efficient separation of these products is difficult. Therefore, there is a need to provide an effective filtration and recovery method to remove and recover as much of compounds to reduce the pollution problem and reutilize the by-products.
Thus, different filtration processes such as continuous rotary pressure filters are adopted for separating by-products contaminants from ATBS. Also, the by-products such as TBAA undergo recrystallization refinement by solvents to be recovered as a crude crystal.
However, the method requires a large excess of methanol water to purify TBAA, and the methanol water used is discarded as waste liquid resulting in an increase in environmental load, thereby providing environmentally and economically disadvantageous. Additionally, researchers are exercising a sublimation method for purification of TBAA, acrylonitrile. However, the process yields and purity of extracting N-tert-butylacrylamide from the kettle residue is low.
Although, these methods are effective for separation of by-products from the ATBS slurry, recovering particular by-products such as acrylonitrile, TBAM suffers from several drawbacks or challenges.
Therefore, there is a long felt need to provide a system for the treatment of the by-products in order to recover useful by-products and alleviate at least the aforementioned drawbacks of the existing processes.
OBJECTS OF THE INVENTION
The principal object of this invention is to provide a system for treatment of the by-products obtained from ATBS synthesis to recover useful by-products such as acrylonitrile, tertiary butyl acrylamide, and others.
Another object of this invention is to provide a continuous process for treatment of the by-products obtained from ATBS synthesis.
Yet another object of this invention is to provide a system and method enabled to recover useful by-products such as acrylonitrile, tertiary butyl acrylamide, and others.
SUMMARY
This summary is provided to introduce concepts related to a system and method for treatment of by-products in the synthesis of ATBS. This summary is not intended to identify essential features of the claimed subject matter, nor it is intended for use in determining or limiting the scope of the disclosed subject matter.
In accordance with an embodiment of the present subject matter, a system and process for treatment of by-products in the acrylamido tertiary butyl sulfonic acid monomer (ATBS) synthesis are described herein.
In one embodiment, the said system comprising of a reactor A enabled for neutralization of byproduct feed (ACRN) to obtain precipitates comprising filtrate I/IV comprising ACRN, and TBAA and ammonium salt. The system may comprise a segregation tank B configured for distilling filtrate I/IV to obtain a pure ACRN distillate and a filtrate II/V comprising TBAA slurry. Further, the said system may comprise a reactor C enabled for treating an ammonium salt solution of acidic moieties and/or sulfuric acid with calcium oxide to obtain calcium salts, liberate ammonia, and recover gypsum. The said system may further comprise a muffle furnace in association with the reactor C enabled for incinerating the calcium salts to obtain white solid mass.
In another embodiment, a process for treatment of by-products in the ATBS slurry is disclosed. The process may include a step of introducing a byproduct feed component in a reactor A, followed by purging ammonia in the reactor A for neutralizing sulfuric acid and acidic moiety from the byproduct feed to obtain neutralized precipitates. The process further may include a step of filtering the neutralized precipitates using a filtering media A, followed by drying at predetermined temperature for predetermined time to obtain dry ammonium salts of acidic moiety and filtrate I. Further, the process may include a step of treating the ammonium salts with calcium oxide in a reactor C to liberate ammonia and to collect Gypsum. The process further may include a step of simultaneously distilling the Filtrate I at 25-35 °C under vacuum in a segregation tank B to separate a pure ACRN distillate and Filtrate II comprising TBAA slurry. Further, the process may include the step of filtering the TBAA slurry using a filtering media B under vacuum to obtain a wet cake of TBAA and byproduct polymeric unit A.
In another embodiment, a process for treatment of by-products in the ATBS slurry is disclosed. The process may include a step of introducing the byproduct feed component in a reactor A, followed by purging ammonia in the reactor A for selectively neutralizing sulfuric acid of the byproduct feed to obtain neutralized precipitates. The process further may include a step of filtering the neutralized precipitates using a filtering media A, followed by drying at predetermined temperature for predetermined time to obtain dry ammonium salt of sulfuric acid and Filtrate IV. Further, the process may include a step of treating the ammonium salt of sulfuric acid with calcium oxide in a reactor C to liberate ammonia and to obtain Gypsum. The process further may include the step of simultaneously distilling the filtrate IV at 25-35 °C under vacuum in a segregation tank B to separate a pure ACRN distillate and filtrate V comprising TBAA slurry and acidic moieties. Further, the process may include a step of treating the TBAA slurry with alkali to neutralize acidic moieties, followed by filtering the treated TBAA slurry using a filtering media B under vacuum to obtain a wet cake of TBAA and byproduct polymeric unit B.
LIST OF ABBREVIATIONS
HPLC – High Pressure Liquid Chromatography
DM – Demineralized water
RBF – Round bottom flask
ATBS – Acrylamido tertiary butyl sulfonic acid
AM – Acrylamide
ACRN – Acrylonitrile
IBDSA – Isobutyl disulfonic acid
IBSA – Isobutyl sulfonic acid
TBA – Tertiary butyl acrylamide
AMPDSA – Acrylamido methyl propane disulfonic acid
BRIEF DESCRIPTION OF DRAWINGS
The detailed description is described with reference to the accompanying Figures. In the Figures, the left-most digit(s) of a reference number identifies the Figure in which the reference number first appears. The same numbers are used throughout the drawings to refer to features and components.
Figure 1 depicts a system 100 for the treatment of the by-products in the ATBS synthesis, in accordance with an embodiment of the present subject matter.
Figure 2 depicts a process 200 for the treatment of the by-products in the ATBS synthesis, in accordance with an embodiment of the present subject matter.
Figure 3 depicts a process 300 for the treatment of the by-products in the ATBS synthesis, in accordance with an embodiment of the present subject matter.
Figure 4 depicts a method 400 for treatment 203 of ammonium salts of acidic moieties and sulfuric acid with lime to liberate ammonia and gypsum, in accordance with an embodiment of the present subject matter.
Figure 5 depicts a method 500 for recycling filtrate obtained from the TBAA slurry at step 204 by multiple cycles, in accordance with an embodiment of the present subject matter.
Figure 6 depicts a method 600 for treatment 203 of ammonium salts of acidic moieties and sulfuric acid with calcium oxide to liberate ammonia and gypsum, in accordance with an embodiment of the present subject matter.
Figure 7 depicts a method 700 for treatment of TBAA slurry with alkali, in accordance with an embodiment of the present subject matter.
DETAILED DESCRIPTION
Reference throughout the specification to “various embodiments,” “some embodiments,” “one embodiment,” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in various embodiments,” “in some embodiments,” “in one embodiment,” or “in an embodiment” in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.
The words “comprising,” “having,” “containing,” and “including,” and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items or meant to be limited to only the listed item or items. It must also be noted that, the singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise. Although any methods similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure, the exemplary methods are described. The disclosed embodiments are merely exemplary of the disclosure, which may be embodied in various forms.
Various modifications to the embodiment may be readily apparent to those skilled in the art and the generic principles herein may be applied to other embodiments. However, one of ordinary skills in the art may readily recognize that the present disclosure is not intended to be limited to the embodiments illustrated but is to be accorded the widest scope consistent with the principles and features described herein. The detailed description of the invention will be described hereinafter referring to accompanied drawings.
Prior to treatment of by-products in the acrylamido tertiary butyl sulfonic acid (ATBS) synthesis, the filtration and purification of the final product is carried out to separate the by-product feed from the pure ATBS.
The byproduct feed includes sulfuric acid and other acid moieties such as 2-methylidene-1,3-propylenedisulfonic acid (IBDSA), 2-methyl-2-propenyl-1-sulfonic acid (IBSA), acrylamido methyl propane disulfonic acid (AMPDSA), AM, ATBS, N-tertiary butyl acrylamide (TBAA) and a combination thereof.
In the existing state of art, referring to figure 1 after synthesis of ATBS in production unit 101, a rotary pressure filter or any other purification unit 102 may be applied to filter out the by-product feed in by-products collection unit 103 and wet cake of ATBS monomer in a storage unit 114. This by-product feed mainly comprises byproduct obtained during the process synthesis which is further treated under different circumstances for recovery of useful components.
In one embodiment, the said system 100 for treatment of the by-products in the ATBS synthesis may comprise of three reactors: a reactor A 104, a segregation tank B 105, and a reactor C 106.
In one embodiment, the reactor A 104 is equipped with an ammonia feed tank 107 for purging ammonia in the reactor A 104 along with stopper, and dip tube. The ammonia feed tank 107 is at least selected from air cooled ammonia feed tank, water cooled ammonia feed tank, evaporative ammonia feed tank, and the like.
In one embodiment, the reactor A 104 in the said system 100 is enabled for neutralization of byproduct feed by ammonia to obtain a slurry containing a mixture of ACRN component, TBAA, and a neutralized precipitate of at least one of ammonium salts of acidic moieties and sulfuric acid. Herein, the byproduct feed contains acidic moieties such as IBSA, IBDSA, AMPDSA and sulfuric acid. In a related embodiment, the amount of purged ammonia from the ammonia feed tank 107 is controlled for adjusting the pH, thereby facilitating selective neutralization either of acidic moieties or sulfuric acid.
In one embodiment, the mixture is filtered via a filtering media A 113 to obtain a filtrate I or filtrate IV comprising ACRN component and TBAA and a neutralized precipitates comprising at least one of ammonium salts of acidic moieties and sulfuric acid.
In a related embodiment, the segregation tank B 105 in the said system 100 is configured for receiving the filtrate I or filtrate IV and mixture of ACRN component and TBAA from the reactor A 104. The segregation tank B 105 in the said system 100 is configured for distilling the filtrate to obtain a pure ACRN distillate in ACRN collection unit 108 and a filtrate II or filtrate V comprising TBAA slurry at a bottom of the segregation tank B 105. The distillation may be optionally performed in rota vapor flask, a flash distillation column, batch distillation column, continuous distillation column, bulb to bulb distillation column or a simple distillation column.
In a related embodiment, the reactor C 106 in said system 100 is enabled for treating an ammonium solution comprising ammonium salts of sulfuric and and/or acid moieties obtained from the reactor A 104 with calcium oxide to obtain gypsum and liberate and recover ammonia. The reactor A 104 may be equipped with a tank such as round bottom flask, an ammonia feed tank 107, a stopper, a thermos-packet and an overhead motor.
In an alternative embodiment, the reactor C 106 is also equipped with an ammonia feed tank 107 for neutralization of acidic moieties such as IBSA, IBDSA present in the ACRN feed.
Further, the system 100 comprises a muffle furnace (not shown) in association with the reactor C106 which is configured for heating and incinerating a white substance obtained in form of calcium salts. Herein, the muffle furnace is selected from electric muffle furnace, box-type furnace, tubular furnace, well type furnace and atmospheric furnace and alike.
The said system 100 further comprises multiple filtering media A 113, filtering media B, and C (not shown in the figure) that are placed in association with the reactor A 104, the segregation tank B 105, and the reactor C106. The separation of the precipitate from the strained solution in the reactor A 104 is performed via the filtering media A. Further the separation of filtrate I and TBAA slurry in the segregation tank B 105 is carried out by means of the filtering media B. The separation of a filtrate (comprising a white solid mass) and wet cake of gypsum in the reactor C 106 is carried out via the filtering media C.
The said system 100 further comprises a tank 108 for collecting pure ACRN, a tank 109 for collecting TBAA, a tank 110 for collecting white solid, a tank 111 for collecting recovered ammonia, a tank 112 for collecting gypsum, and a tank 114 for collecting pure ATBS.
In another embodiment, referring to Figure 2, 4, and 5 a process 200 for treatment of the by-products in the ATBS synthesis using the system 100 is disclosed.
The process 200 may comprise a step of introducing 201 the byproduct feed component in the reactor A 104, followed by purging ammonia in the reactor A 104 for neutralizing the byproduct feed and to obtain a neutralized precipitate and filtrate I. Herein, the byproduct feed may comprise of acidic moieties and other by-products such as IBSA, IBDSA, AM, ACRN, TBAA, AMPDSA, and sulfuric acid. The said step 201 comprises a sub-step of neutralization of the acidic moieties in the byproduct feed 103 to obtain precipitates.
Further, the said process 200 may comprise a step of filtering 202 the precipitates using the filtering media A 113, followed by drying at 60-80 °C for 2-4 hours to obtain dry ammonium salt and filtrate I. The precipitates obtained from neutralizing the byproduct feed are carried out under vacuum for 20-40 minutes.
The neutralized feed precipitate obtained herein in step 201 may include but not limited to ammonium sulfate, ammonium salt of acidic moieties such as IBSA, IBDSA, IBDSA, and AMPDSA and combination thereof. The reactor A 104 may further comprise the filtrate I which is then transferred to the segregation unit B 106. The filtrate I may comprise TBAA component, ACRN, and AM.
Subsequently, referring to figure 2, the said process 200 may comprise a step of treatment 203 of ammonium salt of acidic moieties obtained from the reactor A 104 using calcium oxide in the reactor C 106.
The step of treatment 203 of ammonium salt may include a sub-step of dissolving the dry ammonium salts obtained from the step of neutralization of the byproduct feed in demineralized (DM) water to obtain 25%-85% ammonium solution.
In an embodiment, referring to figures 2 and 4, the step of treatment 203 of ammonium salt may further comprise of various sub-steps as illustrated in figure 4. The step of treatment 203 of ammonium salt may comprise treatment of ammonium salts of acid moieties with calcium oxide in the reactor C 106. As a result of reaction between ammonium salts, liberation and recovery of ammonia from the reactor C 106 is achieved. In another step, calcium slurry comprising calcium salts of acidic moieties is obtained and filtered through the filtering media C to recover wet gypsum on heating. Further, the said step of treating 203 the ammonium salts comprises distillation of filtrate at 70-75°C under vacuum for 80-100 minutes to obtain a solid substance. After the distillation step, the solid substance is heated in a muffle furnace to obtain a white solid mass in the storage tank 110.
Further, a filtrate is obtained which on distilling solid substance comprising calcium salts of acidic moieties is obtained. Further, the step of treatment 203 of ammonium salt may comprise a sub-step of incinerating the white solid mass to eliminate one or more calcium salts of acidic moieties.
In one embodiment, referring figures 2 and 5, the said process 200 may further comprise a step of simultaneously distilling 204 the Filtrate I at 25-35°C under vacuum in the segregation tank B 104 to recover pure ACRN and to obtain a filtrate II comprising a TBAA slurry. The said process 200 may further comprise a step of filtering 205 the filtrate II comprising TBAA slurry using the filtering media B under vacuum to recover wet cake of TBAA. Lastly, the wet cake of TBAA is dried in a hot air oven at 60-80 °C for 1-3 hrs. to obtain dry TBAA 109.
Again, referring to Figure 5, the step of filtering 205 of TBAA slurry may obtain a filtrate III which may comprise a minor remaining quantity of ACRN and TBAA. The filtrate III is then recycled back to the segregation tank B 105 enabled for distillation of ACRN and separation of other crude side products and subjected to step of simultaneous distilling 204 for maximum recovery of pure ACRN and TBAA.
In a related embodiment, the recycling of filtrate III obtained from filtration of TBAA slurry is carried out at least for multiple times such as 4 to 10 times for maximum recovery of the pure ACRN by transferring in the segregation tank B 105 for re-entering at the step of distillation.
In one embodiment, the filtrate III is recycled for at least 10 times. Due to repeated filtration, maximum amount of the TBAA and ACRN is filtered out from the filtrate I, leaving behind the monomeric unit of acrylamide. The filtrate I herein may majorly include acrylamide monomer units and minutely may include salts and TBAA along with ACRN. This monomer on further treatment may be converted to byproduct polymeric unit A of acrylamide.
The process 200 enables the treatment of the by-product of the ATBS synthesis by neutralizing the overall acidic content of the by-product feed, thereby resulting in recovery of ammonia, TBAA, ACRN, and formation of polymer from acrylamide and other monomer as well. The steps of transferring filtrate III back to the segregation tank B 104 not only enables the process 200 continuous but also exhibit economic significance as surplus amount ammonia, TBAA and byproduct polymer of acrylamide are recovered.
Referring to figure 3, in an alternative embodiment, the said process 300 by using the system 100 is disclosed. The process may comprise a step of introducing 301 the byproduct feed component in the reactor A 104 , followed by purging ammonia in the reactor A 104 for selective neutralization of sulfuric acid from the byproduct feed 103 to obtain precipitates. Herein, the byproduct feed may comprise of acidic moieties and other by-products such as unknown impurities, IBSA, IBDSA, AM, ACRN, TBAA, AMPDSA, and sulfuric acid. The said step 301 comprises a sub-step of selective neutralization of the sulfuric acid by adjusting pH of ammonia feed and excluding acidic moieties in the byproduct feed 103 to obtain neutralized sulfuric acid precipitate.
The process 300 may include a step of filtering 302 the neutralized sulfuric acid precipitates using the filtering media A 113, followed by drying at 60-80 °C for 2-4 hours to separate dry ammonium salts of sulfuric acid and a filtrate IV comprising acidic moieties and other by-products such as IBSA, IBDSA, AM, ACRN, TBAA, AMPDSA apart from sulfuric acid. The step of filtering, wherein the filtering and separation of the neutralized precipitates obtained from neutralizing the byproduct feed is performed under vacuum for 20-40 minutes. The process 300 further comprises a step of treating 303 ammonium salts of sulfuric acid using calcium oxide (CaO) in a manner similar to process step 203 of process 200 as explained above.
In one embodiment, referring to figures 3 and 6, the step of treatment 303 of ammonium salt of sulfuric acid is disclosed. The process comprises dissolving the dry ammonium salt in demineralized water in the reactor C 106 to obtain 25%-85% ammonium salt solution of sulfuric acid. The process comprises reaction of ammonium salts of sulfuric acid with calcium oxide in a reactor 106 C. In the next step, the 25%-85% ammonium salt solution is neutralized with calcium oxide, followed by heating at 90-110 °C for 2-3 hr to liberate ammonia in the ammonia collection unit 111 and calcium salt of sulfuric acid i.e., calcium sulfate. Following the heating, the calcium sulfate is filtered through the filtering media C under vacuum to obtain a filtrate and wet cake of gypsum. The obtained wet gypsum is eventually dried in the muffle furnace at 640-660 °C for 1-3 hr to obtain dry gypsum in gypsum collection unit 112.
The obtained wet gypsum is eventually dried in the muffle furnace at 640-660 °C for 1-3 hr to obtain dry gypsum in gypsum collection unit 112. The filtering media A 113, B & C may be selected from Whatman paper, organic filters, woodchips, leaf molds, sand and alike.
Further, the filtrate IV undergoes simultaneous distillation 304 to distill out pure ACRN 108 and obtain a filtrate V comprising TBAA slurry and acidic moieties in the segregation tank B 105.
The filtrate V obtained in the process 300 may also comprise acidic by-product from ATBS synthesis such as other acid moieties 2-methylidene-1,3-propylenedisulfonic acid (IBDSA), 2-methyl-2-propenyl-1-sulfonic acid (IBSA), acrylamido methyl propane disulfonic acid (AMPDSA), AM, ATBS, N-tertiary butyl acrylamide (TBAA) and combination.
Furthermore, in one embodiment referring to figure 3 and 7, the process 300 comprises a step of treating 305 the filtrate V with the alkali selected from at least one of sodium hydroxide, lime, and liquor ammonia to neutralize other acid moieties and to separate TBAA.
Referring to figure 7, in an embodiment, the said process 300 may comprise a step of treatment 305 of filtrate V with alkali liquor ammonia. In related embodiments, alkali treatment can also be carried out using liquor ammonia, NaOH, NH3, and/or lime. The treatment expedites the neutralization of acidic moiety such as IBDSA, IBSA in the filtrate V, thereby obtaining ammonia salts, which further can be used to recover ammonia. Further, water is added to the filtrate V to dissolve the acrylamide units, whereas the TBAA remains insoluble. In an alternative embodiment, the ammonium salts of acidic moieties of IBDSA, IBSA, AMPDSA are subjected to treatment of calcium oxide in the reactor C 106 to recover ammonia and gypsum.
The process 300 may further comprise a step of distillation 306 to separate TBAA from the filtrate V and to obtain filtrate VI. Thus, TBAA and ammonium salts are filtered out from the treated TBAA slurry while leaving behind the filtrate VI. The filtrate VI herein may include but not limited to the minute amount of TBAA, IBSA, IBDSA, ammonium salts and acrylamide monomeric unit. Further, the filtrate VI undergoes polymerization to obtain byproduct polymer product B. This filtrate VI further is used for recovery of monomer units of acrylamide and ammonium salts. In one embodiment, wherein the wet cake of TBAA is dried in hot air oven at 60-80 °C for 1-3 hrs. to obtain dry TBAA.
Moreover, in an alternative embodiment, the filtrates I and IV, filtrates II and V, filtrates III and VI are not restricted to mentioned composition. Also, they may be used interchangeably due to their similar composition.
The process 300 adopted for the treatment of the by-product in the ATBS synthesis not only performs neutralization of feed but also conducts neutralization of remaining acidic content TBAA, thereby resulting in the formation of acrylamide polymer.
The embodiments of the present disclosure are further represented in form of examples and Experimental details.
EXAMPLE 1
A: Neutralization of by-product feed by ammonia:
1180 g of by-product feed (acidity = 1.56%) having HPLC composition 1.30 g (0.11%) of moisture, 0.377 g (0.032%) of IBDSA, 9.09 g (0.771%) of IBSA , 0.25 g (0.021%) AMPDSA, 1.711 g (0.145%) of AM, 0.424 g (0.036%) of ATBS, 12.366 g (1.048%) of TBAA, 1152.718 g (97.688%) of ACRN & 3.422 g (0.29%) of unknowns were taken in 2000 ml round bottom flask equipped with ammonia feed tank for the evaporation losses of ACRN, dip tube for ammonia purging, stopper and overhead motor for stirring. Then, the ammonia gas slowly passed through dip tube into the by-product feed at room temperature till the acidity of the by-product feed became NIL. During this process ammonium sulfate and other ammonium salts of IBSA, IBDSA and ATBS were precipitated out. Then these insoluble were filtered through Whatman filter paper No-42 under vacuum in 30 minutes. After filtration 35.4 g wet cake of ammonium salts of IBSA, IBDSA and ATBS and 1115 g of neutralized ACRN feed (Filtrate I) was obtained respectively. Then 35.4 g wet cake of ammonium salts of IBSA, IBDSA and ATBS on drying at 70°C for 3 hours gives 25 g of dry ammonium salt.
B: Recovery of ACRN from By-product feed by distillation
1115 g of neutralized ACRN feed (filtrate I) was taken in a rota vapor flask for the distillation. The distillation was carried out at 30°C under 720 mmHg of vacuum. After 96% to 98% distillation of neutral ACRN feed (filtrate I), 1032 g of pure ACRN and 23.6 g of TBAA slurry (filtrate II) were obtained.
C: Recovery of TBAA from ACRN feed
Then 23.6 g of TBAA slurry (filtrate II) was filtered through Whatman filter paper No. 42 under vacuum of 720 mmHg. After filtration 14.16 g of filtrate III and 4.72 g wet cake of TBAA were obtained. Then the wet cake of TBAA was dried in hot air oven at 70°C for 2 hrs to obtain 4.43 g of dry TBAA.
EXAMPLE 2
A: Neutralization of ammonia sulfate by calcium oxide
25 g dry of ammonium salts of sulfuric acid, IBSA, IBDSA & ATBS obtained in Step-I were dissolved in 75 g DM water into the 250 ml beaker. Then this 25% ammonium solution was added in 12 g of calcium oxide powder taken in 250 ml RBF equipped with ammonia feed tank, stopper, thermopacket and overhead motor. Then this mixture was heated at 100°C for 2-3 hrs. During this process ammonia gas was liberated and recovered with the formation of calcium sulfate slurry. This neutralization process was monitored by checking the ammonium salt content in the filtrate . When the ammonium salt of the filtrate was NIL, it indicated the complete neutralization of ammonium salt. Then the obtained calcium sulfate slurry was filtered through Whatman paper no -42 under vacuum 720 mmHg. After filtration 64 g of filtrate and 44 g of wet cake of gypsum having moisture in the range of 38 to 40% were obtained. Then 44 g of wet gypsum is heated in a muffle furnace at 650°C for 2 hrs. to obtain 19.6 g of dry gypsum.
B: Recovery of water-soluble impurities from filtrate
64 g of filtrate were taken in the rota vapor distillation set up for distilling out the water at 70-75°C under vacuum of 720 mmHg for 90 minutes. After distillation 9.0 g of solid mass was obtained in the evaporation flask. Then 9.0 g of solid mass were burned in muffle furnace at 650°C for 2 hrs. At this temperature 60% losses of water-soluble impurities were observed. Then 3.6 g white solid mass was obtained.
EXAMPLE 3
A: Neutralization of by-product feed by ammonia
1180 g of by-product feed (acidity = 1.56%) having HPLC composition 1.30 g (0.11%) of moisture, 0.377 g (0.032%) of IBDSA, 9.09 g (0.771%) of IBSA , 0.25 g (0.021%) AMPDSA, 1.711 g (0.145%) of AM, 0.424 g (0.036%) of ATBS, 12.366 g (1.048%) of TBAA, 1152.718 g (97.688%) of ACRN & 3.422 g (0.29%) of Unknowns were taken in 2000 ml Round bottom flask equipped with ammonia feed tank for the evaporation losses of ACRN, dip tube for ammonia purging, stopper and overhead motor for stirring. Then ammonia gas was slowly passed through dip tube into the by-product feed at room temperature till the acidity of the by-product feed became NIL. During this process filtrate I was separated and ammonium sulfate and other ammonium salts of IBSA, IBDSA and ATBS were precipitated out. Then these insoluble were filtered through Whatman filter paper No-42 under vacuum in 30 minutes. After filtration 35.4 g wet cake of ammonium salts of IBSA, IBDSA and ATBS and 1115 g ACRN feed (filtrate I) were obtained respectively. Then 35.4 g wet cake of ammonium salts of IBSA, IBDSA and ATBS on drying at 70°C for 3 hours gives 25 g of dry ammonium salts.
B: Recycling of filtrate III along with filtrate I; Recovery of ACRN from By-product feed by distillation
1115 g of by-product feed (filtrate I) and 14.16 g of filtrate III from example 1 were taken in Rota vapor flask for the distillation and distillation was carried out at 30°C under 720 mmHg of vacuum. After 96% to 98% of neutral ACRN distillation 1050 g of Pure ACRN and 34.0 g of TBAA slurry (filtrate II) were obtained.
C: Recovery of TBAA from by-product feed
Then 34.0 g of TBAA slurry (filtrate II) from part B was filtered through Whatman filter paper No. 42 under vacuum of 720 mmHg. After filtration 20.5 g of filtrateII and 7.0 g wet cake of TBAA and filtrate III were obtained. Then the wet cake of TBAA was dried in hot air oven at 70°C for 2 hrs. After drying 6.5 g of dry TBAA were obtained. The filtrate III was again recycled in by-product feed and continued to recover TBAA and ammonia.
EXAMPLE 4
A: Neutralization of by-product feed by Ammonia:
4000 g of by-product feed having acidity moiety 55.6 g (1.39%), Moisture 4.4 g (0.11%) & sulfuric acid 33.2 g (0.83%) were taken in 5000 ml round bottom flask equipped with ammonia feed tank for the evaporation losses of ACRN, dip tube for ammonia purging, stopper and overhead motor for stirring. Then ammonia gas slowly passes through dip tube into the by-product feed at room temperature till the acidity content of the by-product feed becomes NIL. During this process ammonium salts were precipitated out. Then these ammonium salts were filtered through Whatman filter paper No-42 under vacuum in 30 minutes. After filtration 122 g wet cake of ammonium salt and 3825 g neutralized feed (filtrate I) were obtained respectively. Then 122 g wet cake of ammonium salt was drying at 70°C for 3 hours. Then after drying 83 g of dry ammonium salt were obtained. The 83 g of dry ammonium salt are further treated with calcium oxide for recovery of ammonia and gypsum as per example 2.
B: Distillation of 96 to 97% ACRN from neutralized by-product feed
3825 g of neutralized feed (filtrate I) were taken in rota vapor flask for the distillation and distillation was carried out at 40-45°C under 650-700 mmHg of vacuum. After distillation 150 g TBAA slurry (filtrate II) & 3600 g of Pure ACRN were obtained. Then 150 g TBAA slurry (filtrate II) was filtered through Whatman filter paper no. – 42. After filtration 27 g of wet cake of TBAA and 96 g of filtrate III were obtained. Then 27 g wet cake of TBAA was drying at 70°C for 2 hours. Then after drying 83 g of dry ammonium salt were obtained. Then 96 g of filtrate III were topped up into the next batch of filtrate and continued this process up to the 10th recycle. After the 10th recycling 422 g of dry TBAA, 32.4 kg pure ACRN and 89 g of filtrate III (10th recycle) were obtained.
C: Isolation of TBAA from 10th Recycle filtrate III:
89 g of filtrate III were taken in Rota vapor flask for the distillation and distillation was carried out at 40-45°C under 650-700 mmHg of vacuum. After distillation 53 g TBAA slurry (filtrate II) having 0.03% of IBDSA, 18.12% of AM, 5.75% of IBSA, 0.31% of ACRN, 4.29% of ATBS, 41.46% of TBAA, 0.01% of AMPDSA and 12.24% of moisture and 24 g of Pure ACRN were obtained. Then 53 g of DM water was added into the 53 g of TBAA slurry (filtrate II). The TBAA was precipitated from water filtered through Whatman filter paper no. – 42. After filtration 25 g of wet cake of TBAA and 76 g of filtrate III were obtained. Then 25 g wet cake of TBAA were drying at 70°C for 2 hours. Then after drying 23 g of dry TBAA were obtained. Then 76 g of filtrate III (post 10th recycle) rich with acrylamide and other monomers were used for the polymer preparation.
EXAMPLE 5
A: Sulfuric acid Neutralization of by-product feed by Ammonia:
4000 g of by-product feed having acidic moieties 55.6 g (1.39%), Moisture 4.4 g (0.11%) & sulfuric acid 33.2 g (0.83%) were taken in 5000 ml round bottom flask equipped with ammonia feed tank for the evaporation losses of ACRN, dip tube for ammonia purging, stopper and overhead motor for stirring. Then ammonia gas slowly passed through dip tube into the by-product feed at room temperature till the sulfuric acid content of the by-product feed becomes NIL. During this process ammonium salt was precipitated out. Then this ammonium sulfate was filtered through Whatman filter paper No-42 under vacuum in 30 minutes. After filtration 61 g of wet cake of ammonium sulfate and 3930 g of sulfuric acid neutralized feed (filtrate IV) were obtained respectively. Then 61 g wet cake of ammonium salt were drying at 70°C for 3 hours. Then after drying 45 g of dry ammonium salt were obtained.
B: Distillation of ACRN from sulfuric acid neutralized feed
3930 g of sulfuric acid neutralized feed (filtrate IV) were taken in Rota vapor flask for the distillation and distillation was conducted at 40-45°C under 650-700 mmHg of vacuum. After complete ACRN distillation 48 g of TBAA slurry (filtrate V) & 3505 g of pure ACRN were obtained.
C: Neutralization of TBAA slurry by Liquor Ammonia
48 g of TBAA slurry (filtrate V) and 50 g of water were taken in 250 ml flat bottom kettle. Then 45 g Liquor ammonia were added for the neutralization of remaining acidity of TBAA slurry. This obtained slurry was filtered through Whatman filter paper no. 42. After filtration 25 g wet cake of TBAA & 92 g of neutral filtrate VI were obtained. 25 g wet cake of TBAA was dried at 70°C for 2 hrs and after drying 20.5 g of dry TBAA was obtained. Then 92 g of neutral filtrate VI were used for the byproduct polymer preparation.
EXAMPLE 6
A: Sulfuric acid Neutralization of by-product feed by Ammonia
4000 g of by-product feed having acidic moieties 55.6 g (1.39%), Moisture 4.4 g (0.11%) & sulfuric acid 33.2 g (0.83%) were taken in 5000 ml round bottom flask equipped with ammonia feed tank for the evaporation losses of ACRN, dip tube for ammonia purging, stopper and overhead motor for stirring. Then ammonia gas slowly passed through dip tube into the by-product feed room temperature till the sulfuric acid content of the by-product feed becomes NIL. During this process ammonium salt was precipitated out. Then this ammonium sulfate was filtered through Whatman filter paper No-42 under vacuum in 30 minutes. After filtration 61 g of wet cake of ammonium salt and 3930 g of sulfuric acid neutralized feed (filtrate IV) were obtained respectively. Then 61 g wet cake of ammonium salt were drying at 70°C for 3 hours. Then after drying 45 g of dry ammonium salt were obtained.
B: Distillation of pure ACRN from sulfuric acid neutralized feed
3930 g of sulfuric acid neutralized feed (filtrate IV) were taken in Rota vapor flask for the distillation and distillation was carried out at 40-45°C under 650-700 mmHg of vacuum. After complete ACRN distillation 48 g of TBAA slurry (filtrate V) & 3505 g of pure ACRN were obtained.
EXAMPLE 7
A: Isolation of TBAA from TBAA slurry
48 g of TBAA slurry (filtrate V) and 50 g of water were taken in 250 ml flat bottom kettle. Then slurry was formed due to the precipitation of TBAA. Then this obtained slurry was filtered through Whatman filter paper no. 42. After filtration 25 g wet cake of TBAA & 69 g of acidic filtrate VI were obtained. Then 25 g wet cake of TBAA was dried at 70°C for 2 hrs. After drying 20.5 g dry TBAA were obtained.
B: Neutralization acidic filtrate VI by lime:
69 g of acidic filtrate VI was taken in 250 ml flat bottom kettle. Then 7.0 g lime was added and stirred for 1 hr. After neutralization 76 g of filtrate was obtained. Then this filtrate were used for the polymer preparation.
Although implementations for a system (100) and processes (200, 300) for the treatment of by-products in the ATBS synthesis have been described in language specific to structural features and/or methods, it is to be understood that the appended claims are not necessarily limited to the specific features or methods described. Rather, the specific features and methods are disclosed as examples of implementations of the system (100) and the processes (200, 300) for the treatment of by-products in the ATBS synthesis.

, Claims:WE CLAIM:
1. A process 200 for treatment of by-products in the ATBS synthesis, the process 200 comprising:
introducing 201 a byproduct feed component in a reactor A 104, followed by purging ammonia in the reactor A 104 for neutralizing sulfuric acid and acidic moiety from the byproduct feed to obtain neutralized precipitates;
filtering 202 the neutralized precipitates using a filtering media A 113, followed by drying at predetermined temperature for predetermined time to obtain dry ammonium salts of sulfuric acid and acidic moiety, and filtrate I;
treating 203 the ammonium salts with calcium oxide in a reactor C 106 to liberate ammonia and collect gypsum;
simultaneously distilling 204 the filtrate I at 25-35 °C under vacuum in a segregation tank B 105 to separate a pure ACRN distillate and filtrate II comprising TBAA slurry; and
filtering 205 the TBAA slurry using a filtering media B under vacuum to obtain a wet cake of TBAA and byproduct polymeric unit A.
2. The process 200 as claimed in claim 1, wherein the filtering 202 of neutralized precipitates obtained from neutralizing the byproduct feed is performed under vacuum for 20-40 minutes.
3. The process 200 as claimed in claim 1, wherein the drying of the filtered precipitate is performed at 60-80 °C for 2-4 hours.
4. The process 200 as claimed in claim 1, wherein the acidic moieties comprise IBSA, IBDSA, and AMPDSA and a combination thereof.
5. The process 200 as claimed in claim 1, wherein a filtrate III is obtained from filtration of the filtrate II comprising TBAA slurry and separating wet TBAA cake, wherein the wet cake of TBAA is dried in hot air oven at 60-80 °C for 1-3 hrs. to obtain dry TBAA.
6. The process 200 as claimed in claim 5, wherein the filtrate III is transferred back to the segregation tank 105 for continuous recycling of the filtrate III to recover the TBAA, ACRN and monomeric unit of acrylamide.
7. The process 200 as claimed in claim 5, wherein the byproduct polymeric unit A is prepared from the monomeric unit of acrylamide obtained from the multiple recycling of the filtrate III.
8. The process 203 as claimed in claim 1, wherein the treatment 203 of ammonium salt comprises:
dissolving the dry ammonium salt in demineralized water in the reactor C 106 to obtain 25%-85% ammonium salt solution;
treating the 25%-85% ammonium salt solution with calcium oxide, followed by heating at 90-110 °C for the 2-3 hr to obtain a calcium sulfate and liberation of ammonia gas;
filtering the calcium sulfate through a filtering media C under vacuum to obtain a filtrate and a wet cake of gypsum, wherein the wet gypsum is dried in the muffle furnace at 640-660 °C for 1-3 hr to obtain dry gypsum;
distilling the filtrate in a distillation column at 70-75°C under vacuum for 80-100 minutes to obtain a solid substance; and
incinerating the solid substance in a muffle furnace at 640-660 °C for 1-3 h. to obtain a white solid mass.
9. A process 300 for treatment of by-products in the ATBS synthesis, the process 300 comprising:
introducing 301 the byproduct feed component in a reactor A 104, followed by purging ammonia in the reactor A 104 for selectively neutralizing sulfuric acid of the byproduct feed to obtain neutralized precipitates of sulfuric acid;
filtering 302 the neutralized precipitates using a filtering media A 113, followed by drying at predetermined temperature for predetermined time to obtain dry ammonium salts of sulfuric acid and filtrate IV;
treating 303 the ammonium salts of sulfuric acid 303 with calcium oxide in a reactor C 106 to liberate ammonia;
simultaneously distilling 304 the neutralized feed at 25-35 °C under vacuum in a segregation tank B 105 to separate a pure ACRN distillate and filtrate V comprising TBAA slurry and acidic moieties; and
treating 305 the filtrate V with alkali, followed by filtering the treated filtrate V using a filtering media B under vacuum to obtain a wet cake of TBAA and byproduct polymeric unit B.
10. The process 300 as claimed in claim 9, wherein the filtering 302 of the neutralized precipitates obtained from neutralizing the byproduct feed is performed under vacuum for 20-40 minutes.
11. The process 300 as claimed in claim 9, wherein the drying of the filtered precipitate is performed at 60-80 °C for 2-4 hours.
12. The process 300 as claimed in claim 9, wherein the filtrate V comprising TBAA slurry and acidic moieties is treated with alkali for additional recovery of ACRN to obtain filtrate VI.
13. The process 300 as claimed in claim 12, wherein the alkali is selected from the group comprising liquor ammonia, lime, and NaOH.
14. The process 300 as claimed in claim 12, wherein a filtrate VI and wet cake of TBAA are obtained from filtration of the filtrate V, wherein the wet cake of TBAA is dried in hot air oven at 60-80 °C for 1-3 hrs. to obtain dry TBAA.
15. The process 300 as claimed in claim 14, wherein the byproduct polymeric unit B is prepared from the monomeric unit of acrylamide and sulfonic acids in the filtrate VI.
16. The process 303 as claimed in claim 15, wherein the treatment of ammonium salt comprises:
dissolving the dry ammonium salt in demineralized water in the reactor C 106 to obtain 25%-85% ammonium salt solution of sulfuric acid;
treating the 25%-85% ammonium salt solution with calcium oxide, followed by heating at 90-110 °C for the 2-3 hr to obtain a calcium sulfate and liberation of ammonia gas;
filtering the calcium sulfate through a filtering media C under vacuum to obtain a filtrate and a wet cake of gypsum, wherein the wet gypsum is dried in the muffle furnace at 640-660 °C for 1-3 hr to obtain dry gypsum;
distilling the filtrate in a distillation column at 70-75°C under vacuum for 80-100 minutes to obtain a solid substance; and
incinerating the solid substance in a muffle furnace at 640-660 °C for 1-3 h. to obtain a white solid mass.
17. A system 100 for treatment of by-products in the acrylamido tertiary butyl sulfonic acid (ATBS) synthesis, the system comprising:
a reactor A 104 enabled for neutralization of byproduct feed to obtain precipitates containing a filtrate I/IV comprising ACRN and TBAA slurry and ammonium salt solution;
a segregation tank B 105 configured for distilling the filtrate I/IV comprising ACRN and TBAA slurry to obtain a pure ACRN distillate and a filtrate II/V comprising TBAA slurry;
a reactor C 106 enabled for treating the ammonium salt solution of acidic moieties and/or sulfuric acid with calcium oxide to liberate ammonia and obtain gypsum, and calcium salts; and
a muffle furnace in association with reactor C 106 enabled for incinerating the calcium salts to obtain white solid mass.
18. The system 100 as claimed in claim 17, wherein a plurality of filtering media (A, B, C) is placed in association with the reactors 104, 105, 106 to separate the precipitate from the strained solution, filtering TBAA slurry and separate gypsum respectively.
Dated this 15th day of May 2023

DEEPAK PAWAR
AGENT FOR THE APPLICANT
IN/PA-1454