COMPOSITIONS AND METHODS FOR THE DEGRADATION OF WASTE POLYPROPYLENE

Abstract

Disclosed are methods for polypropylene decomposition. Also disclosed are products obtained from the decomposition polypropylene including carboxylic acids, dicarboxylic acids, nitro-substituted carboxylic acids and dicarboxylic acids; as well as the salts, esters, and anhydrides thereof.

Claims

1. A method for decomposing polypropylene (PP) waste, comprising: a. adding PP waste to a reaction vessel; b. adding at least one oxidizing agent to the reaction vessel to give a mixture, wherein the at least one oxidizing agent is aqueous nitric acid (HNO.sub.3); and c. subjecting the mixture obtained in b. to conditions effective to decompose the PP waste to produce decomposition products, wherein the decomposition products comprise at least one dicarboxylic acid optionally substituted by a nitro group; or the salts or esters or anhydrides thereof.

2. The method of claim 1, wherein the decomposition products further comprise at least one carboxylic acid, optionally substituted by a nitro group.

3. The method of claim 1, wherein the PP waste further comprises at least one plastic material; and at least one non-plastic material.

4. The method of claim 3, wherein the plastic material is selected from the group consisting of plastic film, plastic foam, plastic packaging, plastic bags, plastic wrap, and combinations thereof.

5. The method of claim 3, wherein the non-plastic material is selected from the group consisting of non-plastic organic material, inorganic material, fluid, and combinations thereof.

6-7. (canceled)

8. The method of claim 1, wherein the nitric acid has a concentration of 10-100 wt %.

9. The method of claim 1, wherein the nitric acid has a concentration of about 67 to about 70 wt %.

10. The method of claim 1, wherein the weight ratio of nitric acid to PP is at least 3:1.

11. The method of claim 1, wherein the weight ratio of nitric acid to PP is at least 10:1.

12. (canceled)

13. The method of claim 1, wherein the conditions comprise a temperature range from 60° C. to 200° C.

14. The method of claim 1, wherein the conditions comprise an initial pressure range of 0 psi to 1000 psi.

15. The method of claim 9, wherein the conditions comprise the presence of a gas that is at least one selected from the group consisting of comprising air, nitrogen (N.sub.2), oxygen (O.sub.2), and combinations thereof.

16. The method of claim 1, wherein the conditions comprise a residence time in the reaction vessel of 30 minutes to 30 hours.

17. The method of claim 1, wherein the dicarboyxlic acid or dicarboxylic acid substituted with at least one nitro group is substituted with one or more methyl groups.

18. The method of claim 1, wherein the decomposition products comprise at least one C.sub.4-C.sub.15 dicarboxylic acid.

19-27. (canceled)

28. The method of claim 1, further comprising adding at least one solid state catalyst to the reaction vessel.

29. The method of claim 28, wherein the at least one solid state catalyst is zeolite, alumina, silico-alumino-phosphate, sulfated zirconia, zinc oxide, titanium oxide, zirconium oxide, niobium oxide, iron carbonate, calcium carbide, or combinations thereof.

30. The method of claim 1, further comprising separating the decomposition products into a solid phase and a liquid phase.

31. The method of claim 30, wherein the solid phase comprises at least one of oligomer, polymer, or combinations thereof.

32. The method of claim 30, wherein the solid phase further comprises at least one solid state catalyst.

33. The method of claim 30, wherein the liquid phase comprises a carboxylic acid, dicarboxylic acid, carboxylic acid substituted with a nitro group, or dicarboxylic acid substituted with a nitro group, or the salt, or ester or anhydride thereof.

34. The method of claim 2, further comprising converting the carboxylic acid optionally substituted with a nitro group and/or the dicarboxylic acid optionally substituted with a nitro group into an ester.

35. The method of claim 2 further comprising separating the carboxylic acid optionally substituted with a nitro group and/or the dicarboxylic acid optionally substituted with a nitro group, or the salts, or esters or anhydrides thereof.

36. The method of claim 34, further comprising separating the at least one corresponding ester.

37. The method of claim 36, wherein the ester is at least one of 2-methylsuccinic acid, dimethyl ester; 3-methylglutaric acid, dimethyl ester; 2,4-dimethylglutaric acid, dimethyl ester; 2,4-dimethyladipic acid, dimethyl ester; 3,5-diethylpimelic acid, dimethyl ester; 2,4,6-trimethylpimelic acid, dimethyl ester; 4,6-trimethylsebacic acid, dimethyl ester; 2,4,6,8-tetramethyl-azelaic acid; or a combination thereof.

38. The method of claim 31, further comprising feeding the oligomer, the polymer, and combinations thereof back into the reaction vessel.

39. The method of claim 30, wherein the liquid phase further comprises the at least one oxidizing agent.

40. The method of claim 39, further comprising collecting and regenerating the at least one oxidizing agent.

41. A composition, comprising 2-methylsuccinic acid, 3-methylglutaric acid, 2,4-dimethylglutaric acid, 2,4-dimethyladipic acid, 3,5-dimethylpimelic acid, 2,4,6-trimethylpimelic acid, 2,4,6-trimethylsebacic acid, and 2,4,6,8-tetramethyl-azelaic acid, or the salts, or esters or anhydrides thereof.

42. The composition of claim 41, further comprising at least one of Butanedioic acid, methyl-, dimethyl ester; Butanedioic acid, methyl-, dimethyl ester; Butanedioic acid, methyl-, dimethyl ester; Pentanedioic acid, 2,4-dimethyl-, dimethyl ester; 1,4-Benzenedicarbonitrile, 2-formyl-1H-; Pentanedioic acid, 2,4-dimethyl-, dimethyl ester; 5-Acetoxy-3-methyl-hexanoic acid, methyl ester; 9-Decenoic acid, 2,4-dimethyl-, methyl ester, (R,R)-(−)-; Heptanedioic acid, 2-methyl-, dimethyl ester; Heptanedioic acid, 3,5-dimethyl-, dimethyl ester; Quinoline, 2-butyl; Cyclohexanecarboxylic acid, ethyl ester; 3-Cyclobut-1-enyl-hydroxy-2-methyl-propionic acid, methyl ester; Adipic acid, methyl propyl ester; Methyl 2-methyl-3-cyclopropylpropanoate; 2-Propanone, 1-cyclopentyl-3-ethoxy-; Cyclohexane, 1,2-diethyl-, cis-; Cyclohexane, 1,2-diethyl-3-methyl-; Octanedioic acid, 2,2,7,7-tetramethyl-; 9-Decenoic acid, 2,4-dimethyl-, methyl ester, (2S, 4R)-(+)-; O-Fluoroacetophenone oxime; Cyclohexanone, 2-(1-mercapto-1-methylethyl)-5-methyl-, trans-; Dibenzo[b,f]oxepin-3-ylamine; Carbamic acid, (4-ethoxyphenyl)-, ethyl ester; Quinoline, 2-(1-methyl-1H-imidazol-4-yl)-; 2,8-Bis(1,5,5-trimethylpyrrolidin-2,4-dion-3-ylidene)-3,7-diazanonan; 2-Amino-3,5,7,8-tetrahydro-4,6-pteridinedione; or 1,2-Dimethoxy-4-(1,2-dimethoxyethyl)benzene, or the salts or the esters or the anhydrides thereof.

Description

EXAMPLES

[0175] The invention is further illustrated by the following examples which are intended to be purely exemplary of the invention, and which should not be construed as limiting the invention in any way. The following examples are illustrative only, and are not intended to limit, in any manner, any of the aspects described herein. The following examples are provided to better illustrate the claimed invention and are not to be interpreted as limiting the scope of the invention. To the extent that specific materials are mentioned, it is merely for purposes of illustration and is not intended to limit the invention. One skilled in the art may develop equivalent means or reactants without the exercise of inventive capacity and without departing from the scope of the invention.

Example 1

[0176] The feedstock for this example was PP. This feedstock was food storage containers but different molds including lunch boxes, margarine containers, yogurt pots, syrup bottles, prescription bottles and some plastic bottle caps, all made of PP. These were contaminated with dirt or some level of organic matter and shredded into 0.5 inch to 1.5-inch squares or strips.

[0177] Typically, 5 grams (1 to 7 grams) of the PP strips were added to a glass round bottom flask. 100 grams of concentrated nitric acid (20% to 70% nitric diluted with 30 to 80% water) was added to the round bottom flask. The contents in the round bottom flask was heated using a heating mantle to desired temperature of 120° C. (refluxed) while the contents were continuously stirred. Once refluxing started/ desired temperature was reached, the reaction continued for 6 hours (1 to 24 hours). After the completion of reaction, the round bottom flask was cooled down to room temperature. The reaction generates significant amount of gases that escape during the reaction. The reaction conditions are summarized in Table 1.

[0178] The final mixture consisted of solids (unreacted/partially reacted PP), liquid solution (nitric acid and water mixture) and products dissolved in the liquid solution. The liquid solution was pipetted out to separate it from the solids or the solids were separated using a glass fiber filter paper. The liquid solution was then decanted into a glass beaker and nitric acid/water mixture was evaporated overnight at 60° C. The left-over products in the glass beaker were analyzed on various analytical instruments for its chemical composition.

Example 2

[0179] The feedstock for this example was PP. This feedstock were food storage containers of different molds including lunch boxes, margarine containers, yogurt pots, syrup bottles, prescription bottles and some plastic bottle caps made of PP. These were contaminated with dirt or some level of organic matter and shredded into 0.5-inch to 1.5-inch squares or strips.

[0180] Typically, 5 grams (1 to 7 grams) of the PP strips were placed in a glass liner. 100 grams of concentrated nitric acid (20% to 70% nitric diluted with 30 to 80% water) was added to the liner and loaded into the reactor vessel. The reactor was sealed, purged with inert gas (nitrogen/argon/helium) and the reactor was pressurized with air between 0 psi to 600 psi. Then, the reactor was heated to desired temperature of 120° C. (120 to 150° C.) while the contents were continuously stirred. Once the internal temperature of the reaction vessel reached the target temperature, the reaction continued for 120 min (2 hours). After 2 hours (completion of reaction), the reactor was cooled down to room temperature with continuous stirring. The reaction generated significant amount of gases which leaves the reactor under pressure (10-100 psi) even after cool down. The reaction conditions are summarized in Table 1.

[0181] Once the reactor cooled down, the gases were vented and the reactor was purged with inert gas to remove trapped gases. The final mixture consisted of solids (unreacted/partially reacted PP), liquid solution (nitric acid and water mixture) and products dissolved in the liquid solution. The liquid solution was pipetted out to separate it from the solids or the solids were separated using a glass fiber filter paper. The liquid solution was then decanted into a glass beaker and nitric acid/water mixture was evaporated overnight at 60° C. The left-over products in the glass beaker were analyzed on various analytical instruments for its chemical composition.

TABLE-US-00001 TABLE 1 mass lost max as gases HNO.sub.3 target max pressure time at during solids expt open/closed conc solution:solids temp temp observed temp reaction recovered number vessel (wt %) ratio (w/w) (° C.) observed (psig*) (h) (%) (%) 1.1 open 25 20:1 reflux reflux 0 6 Not 100 recorded 1.2 open 50 20:1 reflux reflux 0 6 Not 109 recorded 1.3 open 70 20:1 reflux reflux 0 6 −14.1 Not recorded 1.4 open 50 10:1 reflux reflux 0 6 −2.3 115 1.5 open 70 10:1 reflux reflux 0 6 −17.8 88 1.6 open 50 20:1 reflux reflux 0 24 −6.4 59 1.7 open 70 20:1 reflux reflux 0 24 −14.7 37 1.8 open 50 20:1 reflux reflux 0 1 −0.7 102 1.9 open 70 20:1 reflux reflux 0 1 −3.3 107 1.10 open 50 70:1 reflux reflux 0 6 −0.3 117 1.11 open 70 70:1 reflux reflux 0 6 −5.6 53 2.1 closed 70 20:1 120 139 248 2 Not Not recorded recorded 2.2 closed 25  7:1 160 169 851 2 Not 94% recorded 2.3 closed 25  7:1 180 194 1635 2 Not 78% recorded 2.4 closed 25  7:1 200 225 2539 2 Not 84% recorded *psig is gauge pressure.

[0182] Table 2 shows the products of the reaction as determined by LCMS.

TABLE-US-00002 TABLE 1 Summary of typical LCMS results from Example 2. Retention m/z time (—) Assignment Comment 1.514 147 1.813 143 1.902 131 2-methylsuccinic Matches commercial acid sample 2.104 145 3-methylglutaric acid Matches commercial sample 2.201 157 2.260 189 2.387 229 2.484 157 2.618 159 2,4-dimethylglutaric Matches commercial acid sample 2.991 173 2,4-dimethyladipic acid 3.268 187 3,5-dimethylpimelic acid 3.417 271, 285 3.775 201 2,4,6- trimethylpimelic acid 4.051 215 2,4,6- trimethylsebacic acid 4.454 313 4.700 243 2,4,6,8-tetramethyl- azelaic acid 4.916 495 5.677 579

[0183] Table 3 depicts a summary of typical GCMS results from Example 2 (with peaks representing >1% of total peak area).

TABLE-US-00003 TABLE 3 Pk# RT Area % Library/ID Ref# CAS# Qual 3 9.181 8.17 C:\Database\NIST11.L Butanedioic acid, methyl-, dimethyl ester 31111 001604-11-1 91 Butanedioic acid, methyl-, dimethyl ester 31113 001604-11-1 83 Butanedioic acid, methyl-, dimethyl ester 31114 001604-11-1 74 5 10.879 4.57 C:\Database\NIST11.L Pentanedioic acid, 2,4-dimethyl-, 52114 002121-68-8 38 dimethyl ester 1,4-Benzenedicarbonitrile, 2-formyl- 29171 164932-42-7 12 1H-Cyclopenta[c]thiophene, hexahydro-, cis- 12355 053907-80-5 10 6 11.234 15.21 C:\Database\NIST11.L Pentanedioic acid, 2,4-dimethyl-, 52114 002121-68-8 86 dimethyl ester 1H-Cyclopenta[c]thiophene, hexahydro-, cis- 12355 053907-80-5 14 Furan, 2-methyl-5-(methylthio)- 12169 013678-59-6 12 10 12.443 13.22 C:\Database\NIST11.L 5-Acetoxy-3-methyl-hexanoic acid, 62293 1000192-54-4 94 methyl ester 9-Decenoic acid, 2,4-dimethyl-, 71142 031183-23-0 38 methyl ester, (R,R)-(−)- Heptanedioic acid, 2-methyl-, 62286 033658-48-9 38 dimethyl ester 12 13.719 2.60 C:\Database\NIST11.L Heptanedioic acid, 3,5-dimethyl-, 73901 104116-37-2 90 dimethyl ester 49554 007661-39-4 43 Quinoline, 2-butyl- Cyclohexanecarboxylic acid, ethyl 29080 003289-28-9 25 ester 13 13.974 16.53 C:\Database\NIST11.L 3-Cyclobut-1-enyl-3-hydroxy-2-methyl- 38916 1000190-69-7 27 propionic acid, methyl ester Adipic acid, methyl propyl ester 62256 1000324-51-9 27 Methyl 2-methyl-3-cyclopropylpropanoate 19804 062021-35-6 22 16 15.129 10.03 C:\Database\NIST11.L 2-Propanone, 1-cyclopentyl-3-ethoxy- 38039 051149-71-4 14 Cyclohexane, 1,2-diethyl-, cis- 18036 000824-43-1 11 Cyclohexane, 1,2-diethyl-3-methyl- 27092 061141-80-8 11 17 16.338 6.86 C:\Database\NIST11.L Octanedioic acid, 2,2,7,7-tetramethyl- 85774 016386-99-5 43 9-Decenoic acid, 2,4-dimethyl-, 71145 031183-24-1 14 methyl ester, (2S,4R)-(+)- O-Fluoroacetophenone oxime 26538 000364-81-8 11 20 17.426 2.01 C:\Database\NIST11.L meta-Methoxybenzenethiol 18376 015570-12-4 15 Cyclohexanone, 2-(1-mercapto-1- 49945 033281-91-3 15 methylethyl)-5-methyl-, trans- Benzenethiol, 4-methoxy- 18378 000696-63-9 15 23 19.079 1.16 C:\Database\NIST11.L Dibenzo[b,f]oxepin-3-ylamine 68691 1000304-76-7 35 Carbamic acid, (4-ethoxyphenyl)-, 68521 1000319-47-6 35 ethyl ester Quinoline, 2-(1-methyl-1H-imidazol- 68651 002552-96-7 30 4-yl)- 24 19.268 1.75 C:\Database\NIST11.L 2,8-Bis(1,5,5-trimethylpyrrolidin- 213610 1000286-75-3 50 2,4-dion-3-ylidene)-3,7-diazanonan 2-Amino-3,5,7,8-tetrahydro-4,6- 46535 001011-23-0 38 pteridinedione 1,2-Dimethoxy-4-(1,2-dimethoxyethyl)benzene 82440 1000333-50-1 27

[0184] The various methods and techniques described above provide a number of ways to carry out the application. Of course, it is to be understood that not necessarily all objectives or advantages described can be achieved in accordance with any particular embodiment described herein. Thus, for example, those skilled in the art will recognize that the methods can be performed in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objectives or advantages as taught or suggested herein. A variety of alternatives are mentioned herein. It is to be understood that some embodiments specifically include one, another, or several features, while others specifically exclude one, another, or several features, while still others mitigate a particular feature by inclusion of one, another, or several advantageous features.

[0185] Furthermore, the skilled artisan will recognize the applicability of various features from different embodiments. Similarly, the various elements, features and steps discussed above, as well as other known equivalents for each such element, feature or step, can be employed in various combinations by one of ordinary skill in this art to perform methods in accordance with the principles described herein. Among the various elements, features, and steps some will be specifically included and others specifically excluded in diverse embodiments.

[0186] Although the application has been disclosed in the context of certain embodiments and examples, it will be understood by those skilled in the art that the embodiments of the application extend beyond the specifically disclosed embodiments to other alternative embodiments and/or uses and modifications and equivalents thereof.

[0187] Various embodiments of this application are described herein, including the best mode known to the inventors for carrying out the application. Variations on those embodiments will become apparent to those of ordinary skill in the art upon reading the foregoing description. It is contemplated that skilled artisans can employ such variations as appropriate, and the application can be practiced otherwise than specifically described herein. Accordingly, many embodiments of this application include all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the application unless otherwise indicated herein or otherwise clearly contradicted by context.

[0188] All patents, patent applications, publications of patent applications, and other material, such as articles, books, specifications, publications, documents, things, and/or the like, referenced herein are hereby incorporated herein by this reference in their entirety for all purposes, excepting any prosecution file history associated with same, any of same that is inconsistent with or in conflict with the present document, or any of same that may have a limiting affect as to the broadest scope of the claims now or later associated with the present document. By way of example, should there be any inconsistency or conflict between the description, definition, and/or the use of a term associated with any of the incorporated material and that associated with the present document, the description, definition, and/or the use of the term in the present document shall prevail.

[0189] It is to be understood that the embodiments of the application disclosed herein are illustrative of the principles of the embodiments of the application. Other modifications that can be employed can be within the scope of the application. Thus, by way of example, but not of limitation, alternative configurations of the embodiments of the application can be utilized in accordance with the teachings herein. Accordingly, embodiments of the present application are not limited to that precisely as shown and described.

[0190] Various embodiments of the invention are described above in the Detailed Description. While these descriptions directly describe the above embodiments, it is understood that those skilled in the art may conceive modifications and/or variations to the specific embodiments shown and described herein. Any such modifications or variations that fall within the purview of this description are intended to be included therein as well. Unless specifically noted, it is the intention of the inventors that the words and phrases in the specification and claims be given the ordinary and accustomed meanings to those of ordinary skill in the applicable art(s).

[0191] The foregoing description of various embodiments of the invention known to the applicant at this time of filing the application has been presented and is intended for the purposes of illustration and description. The present description is not intended to be exhaustive nor limit the invention to the precise form disclosed and many modifications and variations are possible in the light of the above teachings. The embodiments described serve to explain the principles of the invention and its practical application and to enable others skilled in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed for carrying out the invention.

[0192] While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that, based upon the teachings herein, changes and modifications may be made without departing from this invention and its broader aspects and, therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true spirit and scope of this invention.