Polyester process using a pipe reactor
View Patent ↗The invention is directed to polyester processes that utilizes a pipe reactor in the esterification, polycondensation, or both esterification and polycondensation processes. Pipe reactor processes of the present invention have a multitude of advantages over prior art processes including improved heat transfer, volume control, agitation and disengagement functions.
1. A process for making an ester from a plurality of reactants comprising:
(a) providing an esterification pipe reactor having a first inlet and a first outlet;
(b) adding the reactants under esterification reaction conditions into the esterification pipe reactor proximal to the first inlet and forming a two phase flow so the reactants form a liquid phase and vapor phase through the esterification pipe reactor, wherein the esterification pipe reactor is operated in at least one flow regime selected from the group consisting of bubble flow, plug flow, stratified flow, wavy flow, slug flow, dispersed flow and froth flow and wherein at least a portion of the reactants form an ester monomer; wherein said ester has a diethlyene glycol content of less than 1.4 weight percent.
2. The process of claim 1 wherein at least a portion of the ester monomer is reacted in the esterification pipe reactor to form an ester oligomer.
3. The process of claim 2 further comprising:
(c) reacting the ester oligomer under polycondensation reaction conditions in a polycondensation pipe reactor wherein at least a portion of the oligomer forms a polyester.
4. The process of claim 1 further comprising:
(c) reacting the ester monomer under polycondensation reaction conditions in a polycondensation pipe reactor wherein at least a portion of the ester monomer forms an ester oligomer.
5. The process of claim 4 further comprising:
(d) reacting the ester oligomer under polycondensation reaction conditions in the polycondensation pipe reactor wherein at least a portion of the oligomer forms a polyester.
6. The process of claim 1 wherein said reactants comprise a diacid or diacid generator and a diol or diol generator.
7. The process of claim 6 wherein said diacid or diacid generator is selected from the group consisting of aromatic dicarboxylic acids having 8 to 14 carbon atoms, aliphatic dicarboxylic acids having 4 to 12 carbon atoms, and cycloaliphatic dicarboxylic acids having 8 to 12 carbon atoms and esters of these diacids; and wherein said diol or diol generator is selected from the group consisting cycloaliphatic diols having 6 to 20 carbon atoms and aliphatic diols having 3 to 20 carbon atoms.
8. The process of claim 6 wherein said diacid or diacid generator and said diol or diol generator are selected from the group consisting of terephthalic acid, phthalic acid, isophthalic acid, naphthalene-2,6-dicarboxylic acid, cyclohexanedicarboxylic acid, cyclohexanediacetic acid, diphenyl-4,4′-dicarboxylic acid, dipheny-3,4′-dicarboxylic acid, 2,2,-dimethyl-1,3-propandiol, dicarboxylic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, dimethyl terephthalate, ethylene glycol, diethylene glycol, triethylene glycol, 1,4-cyclohexane-dimethanol, propane-1,3-diol, pentane-1,5-diol, hexane-1,6-diol, neopentylglycol, 3-methylpentanediol-(2,4), 2-methylpentanediol-(1,4), 2,2,4-trimethylpentane-diol-(1,3), 2-ethylhexanediol-(1,3), 2,2-diethylpropane-diol-(1,3), hexanediol-(1,3), 1,4-di-(hydroxyethoxy)-benzene, 2,2-bis-(4-hydroxycyclohexyl)-propane, 2,4-dihydroxy-1,1,3,3-tetramethyl-cyclobutane, 2,2,4,4 tetramethylcyclobutanediol, 2,2-bis-(3-hydroxyethoxyphenyl)-propane, 2,2-bis-(4-hydroxypropoxyphenyl)-propane, isosorbide, hydroquinone, BDS-(2,2-(sulfonylbis)4,1-phenyleneoxy))bis(ethanol), and mixtures thereof.
9. The process of any one of claims 3 to 8 wherein said ester is poly(ethylene terephthalate).
10. The process of claim 6 , 7 or 8 wherein said diacid or diacid generator are selected from the group consisting of terephthalic acid and dimethyl terephthalate, and said diol is ethylene glycol.
11. The process of any one of claims 1 to 5 wherein at least one of the pipe reactors has a means for recycling a portion of the process fluid, and the process comprises recycling a portion of the process fluid to the esterification pipe reactor.
12. The process of any one of claims 3 to 5 wherein at least one of the pipe reactors has a means for recycling a portion of the process fluid, and the process comprises recycling a portion of the process fluid to the polycondensation pipe reactor.
13. The process of claim 11 further comprising adding at least one reactant into the recycled process fluid.
14. The process of any one of claims 3 , 4 , or 5 wherein the polycondensation pipe reactor has a plurality of zones or stages and the process comprises operating at least two of the zones or stages at a pressure differential.
15. The process of any one of claims 1 to 5 further comprising removing a portion of the vapor from at least one of the pipe reactors.
16. The process of claim 15 comprising operating the esterification pipe reactor in a bubble or froth regime.
17. The process of claim 14 comprising operating the polycondensation pipe reactor in a stratified flow regime.
18. The process of claim 1 further including adding to the pipe reactor at least one material selected from the group consisting of a catalytic material, colorant, toner, pigment, carbon black, glass fiber, filler, impact modifier, antioxidant, stabilizer, flame retardant, reheat aid, acetaldehyde reducing compound, oxygen scavenging compound, UV absorbing compound, barrier improving additive, black iron oxide and mixtures thereof.
19. The process of claims 1 to 5 , 16 , or 17 wherein the pipe reactor is a substantially empty pipe.
20. The process of any one of claims 1 to 5 wherein the esterification pipe reactor is operated with a pressure profile between the first inlet and the first outlet and wherein the pressure at the first inlet is greater than the pressure at the first outlet.
21. The process of claim 20 wherein the pressure profile is established by a hydrostatic pressure inside the esterification pipe reactor.
22. The process of any one of claims 3 to 5 further comprising controlling the pressure between the esterification process and polycondensation process using a seal leg in fluid communication with and positioned between the esterification pipe reactor and the polycondensation pipe reactor.
23. The process of claim 22 further comprising heating the fluid in said seal leg.
24. The process of claim 23 wherein the fluid in the seal leg is heated to a boiling temperature.
25. The process of claim 15 further comprising recovering reactants from the removed vapor to form a reactant lean overhead product and a reactant rich bottom product.
26. The process of claim 15 further comprising oxidizing the removed vapor in an oxidizer selected from a heat transfer media furnace, an incinerator or a thermal oxidizer.
27. The process of claim 25 further comprising oxidizing the reactant lean overhead product in an oxidizer selected from a heat transfer media furnace, an incinerator or a thermal oxidizer.
28. The process of claim 25 further comprising recycling the reactant rich bottom product to the esterification pipe reactor.
29. The process of any one of claims 25 to 28 wherein at least one of said reactants is glycol.
30. The process of any one of claims 1 to 5 further comprising retrofitting said pipe reactor to a conventional polyester process having at least one continuous stirred tank reactor.
31. A process for making an ester from a plurality of reactants comprising:
(a) providing an esterification pipe reactor having a first inlet and a first outlet;
(b) adding the reactants under esterification reaction conditions into the esterification pipe reactor proximal to the first inlet and forming a two phase flow so the reactants form a liquid phase and vapor phase through the esterification pipe reactor; wherein at least a portion of the reactants form an ester monomer; wherein said ester has a diethlyene glycol content of less than 1.4 weight percent; and wherein conversion is greater than 85%.
32. The process of claim 31 wherein at least a portion of the ester monomer is reacted in the esterification pipe reactor to form an ester oligomer.
33. The process of claim 32 further comprising:
(c) reacting the ester oligomer under polycondensation reaction conditions in a polycondensation pipe reactor wherein at least a portion of the oligomer forms a polyester.
34. The process of claim 31 further comprising:
(c) reacting the ester monomer under polycondensation reaction conditions in a polycondensation pipe reactor wherein at least a portion of the ester monomer forms an ester oligomer.
35. The process of claim 34 further comprising:
(d) reacting the ester oligomer under polycondensation reaction conditions in the polycondensation pipe reactor wherein at least a portion of the oligomer forms a polyester.
36. The process of claim 31 wherein said reactants comprise a diacid or diacid generator and a diol or diol generator.
37. The process of claim 36 wherein said diacid or diacid generator is selected from the group consisting of aromatic dicarboxylic acids having 8 to 14 carbon atoms, aliphatic dicarboxylic acids having 4 to 12 carbon atoms, and cycloaliphatic dicarboxylic acids having 8 to 12 carbon atoms and esters of these diacids; and wherein said diol or diol generator is selected from the group consisting cycloaliphatic diols having 6 to 20 carbon atoms and aliphatic diols having 3 to 20 carbon atoms.
38. The process of claim 36 wherein said diacid or diacid generator and said diol or diol generator are selected from the group consisting of terephthalic acid, phthalic acid, isophthalic acid, naphthalene-2,6-dicarboxylic acid, cyclohexanedicarboxylic acid, cyclohexanediacetic acid, diphenyl-4,4′-dicarboxylic acid, dipheny-3,4′-dicarboxylic acid, 2,2,-dimethyl-1,3-propandiol, dicarboxylic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, dimethyl terephthalate, ethylene glycol, diethylene glycol, triethylene glycol, 1,4-cyclohexane-dimethanol, propane-1,3-diol, pentane-1,5-diol, hexane-1,6-diol, neopentylglycol, 3-methylpentanediol-(2,4), 2-methylpentanediol-(1,4), 2,2,4-trimethylpentane-diol-(1,3), 2-ethylhexanediol-(1,3), 2,2-diethylpropane-diol-(1,3), hexanediol-(1,3), 1,4-di-(hydroxyethoxy)-benzene, 2,2-bis-(4-hydroxycyclohexyl)-propane, 2,4-dihydroxy-1,1,3,3-tetramethyl-cyclobutane, 2,2,4,4 tetramethylcyclobutanediol, 2,2-bis-(3-hydroxyethoxyphenyl)-propane, 2,2-bis-(4-hydroxypropoxyphenyl)-propane, isosorbide, hydroquinone, BDS-(2,2-(sulfonylbis)4,1-phenyleneoxy))bis(ethanol), and mixtures thereof.
39. The process of any one of claims 33 to 38 wherein said ester is poly(ethylene terephthalate).
40. The process of claim 36 , 37 or 38 wherein said diacid or diacid generator are selected from the group consisting of terephthalic acid and dimethyl terephthalate, and said diol is ethylene glycol.
41. The process of any one of claims 31 to 35 wherein at least one of the pipe reactors has a means for recycling a portion of the process fluid, and the process comprises recycling a portion of the process fluid to the esterification pipe reactor.
42. The process of any one of claims 33 to 35 wherein at least one of the pipe reactors has a means for recycling a portion of the process fluid, and the process comprises recycling a portion of the process fluid to the polycondensation pipe reactor.
43. The process of claim 41 further comprising adding at least one reactant into the recycled process fluid.
44. The process of any one of claims 33 , 34 , or 35 wherein the polycondensation pipe reactor has a plurality of zones or stages and the process comprises operating at least two of the zones or stages at a pressure differential.
45. The process of any one of claims 31 to 35 further comprising removing a portion of the vapor from at least one of the pipe reactors.
46. The process of claim 45 comprising operating the esterification pipe reactor in a bubble or froth regime.
47. The process of claim 46 comprising operating the polycondensation pipe reactor in a stratified flow regime.
48. The process of claim 31 further including adding to the pipe reactor at least one material selected from the group consisting of a catalytic material, colorant, toner, pigment, carbon black, glass fiber, filler, impact modifier, antioxidant, stabilizer, flame retardant, reheat aid, acetaldehyde reducing compound, oxygen scavenging compound, UV absorbing compound, barrier improving additive, black iron oxide and mixtures thereof.
49. The process of claims 31 to 35 , 46 , or 47 wherein the pipe reactor is a substantially empty pipe.
50. The process of any one of claims 31 to 35 wherein the esterification pipe reactor is operated with a pressure profile between the first inlet and the first outlet and wherein the pressure at the first inlet is greater than the pressure at the first outlet.
51. The process of claim 50 wherein the pressure profile is established by a hydrostatic pressure inside the esterification pipe reactor.
52. The process of any one of claims 33 to 35 further comprising controlling the pressure between the esterification process and polycondensation process using a seal leg in fluid communication with and positioned between the esterification pipe reactor and the polycondensation pipe reactor.
53. The process of claim 52 further comprising heating the fluid in said seal leg.
54. The process of claim 53 wherein the fluid in the seal leg is heated to a boiling temperature.
55. The process of claim 45 further comprising recovering reactants from the removed vapor to form a reactant lean overhead product and a reactant rich bottom product.
56. The process of claim 45 further comprising oxidizing the removed vapor in an oxidizer selected from a heat transfer media furnace, an incinerator or a thermal oxidizer.
57. The process of claim 45 further comprising oxidizing the reactant lean overhead product in an oxidizer selected from a heat transfer media furnace, an incinerator or a thermal oxidizer.
58. The process of claim 45 further comprising recycling the reactant rich bottom product to the esterification pipe reactor.
59. The process of any one of claims 55 to 58 wherein at least one of said reactants is glycol.
60. The process of any one of claims 31 to 35 further comprising retrofitting said pipe reactor to a conventional polyester process having at least one continuous stirred tank reactor.