CN101423478A - Method for producing hexane diacid and hexanediamine by using nylon-66 disaggregation - Google Patents
Method for producing hexane diacid and hexanediamine by using nylon-66 disaggregation Download PDFInfo
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- CN101423478A CN101423478A CNA2007101564919A CN200710156491A CN101423478A CN 101423478 A CN101423478 A CN 101423478A CN A2007101564919 A CNA2007101564919 A CN A2007101564919A CN 200710156491 A CN200710156491 A CN 200710156491A CN 101423478 A CN101423478 A CN 101423478A
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- hexanediamine
- workshop section
- nylon
- acid
- solution
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/62—Plastics recycling; Rubber recycling
Abstract
The invention relates to a method for producing hexanedioic acid and hexamethylene diamine by using nylon-66 to depolymerize, which is characterized by comprising the following steps: adding formylic acid and water into a reaction kettle, heating the mixture and adding the nylon-66 into the mixture at the same time, dissolving the nylon-66, adding sulphuric acid into the mixture, making the mixture react for 4 to 10 hours under the condition of keeping pressure intensity between 0.1 and 0.5MPa, so as to obtain acid hydrolysis solution; filtering obtained wet CaSO4.2H2O, and then obtaining dry CaSO4.2H2O and hexamethylene diamine solution by adopting a drying method; and adding Na3PO4 in the production process to prevent CaSO4 from scaling. By adopting the technique, the method can improve production efficiency, reduces even does not use phosphoric acid or phosphate, reduces production cost, improves recovery rate of the hexamethylene diamine, eliminates scaling in the production process, and reduces risk in the running process of equipment.
Description
Technical field
The present invention relates to a kind of method of producing hexanodioic acid, hexanediamine, relate in particular to the method that a kind of nylon-66 disaggregation that is applicable to that industrialized production is used is produced hexanodioic acid, hexanediamine with nylon-66 disaggregation.
Background technology
Nylon-66 is the resin that is formed by hexanodioic acid and hexanediamine polycondensation, in the synthetic and course of processing of reeling off raw silk from cocoons, can produce unacceptable product and tankage such as waste silk, short silk and assorted bits at it.In addition, the goods of various nylon are difficult to handle after being used, and not only cause waste, and environment is polluted, and for example, have many waste carpet material can't handle the method that has all adopted landfill or transport to under-developed country and cause new pollution both at home and abroad.Therefore, recycle waste and old nylon-66 remarkable economic efficiency and social benefit are arranged.
Nylon reclaims and mainly contains certain methods at present: melt pelletization regeneration; Chemical recovery; Energy recovery; Landfill disposal etc.But because the poor heat stability of nylon-66, melt pelletization regeneration back mechanical property descends significantly, and can not repeatedly repeat energy recovery is to adopt oil refining or incendiary method, and not only utility value is low, and atmosphere pollution.And landfill is cured the symptoms, not the disease.Therefore, most major companies adopt mostly is chemical recycling.For example sky, Liaoning becomes chemical industry company limited to declare a kind of Chinese patent of production method of useless nylon recycling, and patent publication No. is CN1569802; Shanxi applied chemistry institute has carried out the pilot scale research that hexanodioic acid, hexanediamine are produced in nylon-66 waste material hydrolysis; Minte Nylon Industry Co., Ltd., Ningbo has applied for a kind ofly producing the Chinese patent of the technology of hexanodioic acid, hexanediamine with nylon-66 disaggregation, and patent publication No. is CN1611477; Du pont company has carried out the experiment of nitric acid depolymerization nylon-66, with hydrogenation method nitric acid hydrogenation ammonification is made hexanediamine.The patent that adopts the poly-nylon-66 of alkaline hydrolysis was declared in China by Holland DSM N. V. in 1998, publication number is CN1205330A.U.S. Pat A-5302756, USA-5233021 have described a kind of at high temperature by amine and adopt the method depolymerization nylon of supercritical extraction respectively.
Yet still there is this following deficiency in above-mentioned chemical recovery method:
1, the time of acidolysis workshop section longer, and adopt phosphoric acid or phosphoric acid salt as catalyzer, production efficiency is not high enough;
2, generally adopt the method for vacuum drying to obtain exsiccant CaSO
42H
2The thick solution of O and hexanediamine extremely consumes energy;
3, the CaSO that in whole production line, generates
4Easily fouling on the wall of reactor or transfer line has a strong impact on the carrying out of production.
Comprehensively above-mentioned, present method of producing hexanodioic acid, hexanediamine with nylon-66 disaggregation requires further improvement.
Summary of the invention
Technical problem to be solved by this invention provides a kind of method of producing hexanodioic acid, hexanediamine with nylon-66 disaggregation, it can accelerate acidolysis reaction speed, do not adopt phosphoric acid or phosphate catalyst, can reduce simultaneously the energy consumption in the drying course, and reducing the formation of the fouling in the whole process, technology is more reasonable and practical.
The present invention solves the problems of the technologies described above the technical scheme that is adopted: a kind of method of producing hexanodioic acid, hexanediamine with nylon-66 disaggregation, its include acidolysis workshop section, crystallisation by cooling workshop section, thick sour centrifugal station, recrystallization workshop section, in and workshop section and refining workshop section form, it is characterized in that each workshop section is as described below:
(1), acidolysis workshop section, formic acid and water are added in the reactor, add nylon-66 while heat then, nylon-66 is dissolved, add sulfuric acid again, under the condition of maintenance pressure, reacted 4～10 hours at 0.1～0.5MPa, obtain acid hydrolysis solution;
(2), crystallisation by cooling workshop section and thick sour centrifugal station, acid hydrolysis solution is entered crystallisation by cooling workshop section through strainer carries out crystallisation by cooling, separate obtaining thick adipic acid crystals and hexanediamine sulfate liquor then;
(3), recrystallization workshop section and refining workshop section, the thick adipic acid crystals that obtains in the step (2) decolour, recrystallization, oven dry obtain refined adipic acid;
(4), in and workshop section, in and add the milk of lime of capacity in the still, and then add the hexanediamine sulfate liquor that step (2) obtains, stir, make to react completely, the pH value of neutralization back solution filters to isolate the solution and the moist CaSO that contain hexanediamine greater than 12
42H
2O;
(5), refining workshop section, the solution that contains hexanediamine that obtains in the step (4) steamed with vacuum follows the example of or extraction process obtains the thick solution of hexanediamine; The CaSO of humidity in the recycling step (4)
42H
2Hexanediamine among the O is with the CaSO of the humidity that obtains in the step (4)
42H
2O filters, and adopts the method for oven dry to obtain exsiccant CaSO
42H
2The thick solution of O and hexanediamine; The thick solution of hexanediamine that obtains is mixed, concentrate the refining purified hexanediamine that obtains; In removal process, add simultaneously Na
3PO
4, to prevent to form CaSO
4Fouling.
The concentration of the formic acid described in step (1) the acidolysis workshop section is 1%～25%, and is wherein preferred 5%, mass percent.
Vacuum fluid bed dryer drying is adopted in oven dry described in the refining workshop section of step (5), and temperature is lower than 160 ℃.Utilize vacuum fluidized-bed drying technology like this, accelerated the speed of oven dry greatly, and make power consumption be about 70% of original technology power consumption.
Adding Na described in the refining workshop section of step (5)
3PO
4Molar weight and CaSO
4Molar weight become 1: 2 relation.Utilize and add Na
3PO
4Reach the fouling that reduces in the reaction process, if can accurately control Na
3PO
4Molar weight and CaSO
4Molar weight become 1: 2, will eliminate fouling basically.Its principle is:
2CaSO
4+PO
4 3-+OH
-→Ca
2(OH)PO
4+2SO
4 2-
Compared with prior art, the invention has the advantages that: utilize formic acid to dissolve earlier, nylon solubilized (or swelling) is in formic acid, at this moment, itself and vitriolic reaction just are liquid/liquid reaction, and original nylon and vitriolic reaction are the solid-liquid reaction, and obviously, the former liquid/liquid speed of response will be apparently higher than the latter's solid-liquid reaction, therefore improved speed of response, also just improve its production efficiency, simultaneously, can not adopt phosphoric acid or phosphoric acid salt.Adopted above-mentioned technology, realized a kind of nylon-66 disaggregation production hexanodioic acid, hexanediamine efficiently, fast and easily, and obtained following effect:
1. improved production efficiency, reduced, reduced production cost not even with phosphoric acid or phosphoric acid salt;
2. utilize vacuum fluidized-bed drying technology, accelerated the speed of oven dry greatly, and make power consumption, also greatly reduce production cost, improved the rate of recovery of hexanediamine for about 70% of original technology power consumption;
3. eliminate the fouling in the production process, reduced the risk in the equipment running process.
Whole technology circuit is more reasonable and practical, economy.
Embodiment
Below in conjunction with embodiment the present invention is described in further detail.
Embodiment 1
A kind of method of producing hexanodioic acid, hexanediamine with nylon-66 disaggregation, it comprises acidolysis workshop section, crystallisation by cooling workshop section, thick sour centrifugal station, recrystallization workshop section, in and workshop section and refining workshop section, each workshop section's step is:
(1), acidolysis workshop section, formic acid and water are added in the reactor, the concentration of control formic acid is 5%, add nylon-66 while heating then,, add sulfuric acid again the nylon-66 dissolving, under the condition of maintenance pressure, reacted 4～10 hours, obtain acid hydrolysis solution at 0.1～0.5MPa;
(2), thick sour centrifugal station and crystallisation by cooling workshop section, acid hydrolysis solution is entered crystallisation by cooling workshop section through coarse filter carries out crystallisation by cooling, separate obtaining thick adipic acid crystals and hexanediamine sulfate liquor then;
(3), refining workshop section, the thick adipic acid crystals that obtains in the step (2) decolour, recrystallization, oven dry obtain refined adipic acid;
(4), in and workshop section, in and add the milk of lime of capacity in the still, and then add the hexanediamine sulfate liquor that step (2) obtains, fully stir, make to react completely, the pH value of neutralization back solution filters to isolate the solution and the moist CaSO that contain hexanediamine greater than 12
42H
2O;
(5), the solution that contains hexanediamine that obtains in the step (4) is steamed with vacuum follow the example of or extraction process obtains the thick solution of hexanediamine;
(6), the CaSO of humidity in the recycling step (4)
42H
2Hexanediamine among the O: with the CaSO of the humidity that obtains in the step (4)
42H
2O filters, and adopts the method for oven dry to obtain exsiccant CaSO
42H
2The thick solution of O and hexanediamine; Vacuum fluid bed dryer drying is adopted in oven dry, and temperature is lower than 160 ℃.In removal process, add Na
3PO
4, to prevent to form CaSO
4Fouling.Preferably will add Na
3PO
4Molar weight and CaSO
4Molar weight constitute 1: 2 relation.
(7), refining workshop section, the thick solution of hexanediamine that obtains in step (5) and the step (6) concentrated to make with extra care obtain the purified hexanediamine.
Embodiment 2
A kind of method of producing hexanodioic acid, hexanediamine with nylon-66 disaggregation, it comprises acidolysis workshop section, crystallisation by cooling workshop section, thick sour centrifugal station, recrystallization workshop section, in and workshop section and refining workshop section, each workshop section's step is:
(1), acidolysis workshop section, formic acid and water are added in the reactor, the concentration of control formic acid is 25%, add nylon-66 while heating then,, add sulfuric acid again the nylon-66 dissolving, under the condition of maintenance pressure, reacted 4～10 hours, obtain acid hydrolysis solution at 0.1～0.5MPa;
(2), thick sour centrifugal station and crystallisation by cooling workshop section, acid hydrolysis solution is entered crystallisation by cooling workshop section through coarse filter carries out crystallisation by cooling, separate obtaining thick adipic acid crystals and hexanediamine sulfate liquor then;
(3), refining workshop section, the thick adipic acid crystals that obtains in the step (2) decolour, recrystallization, oven dry obtain refined adipic acid;
(4), in and workshop section, in and add the milk of lime of capacity in the still, and then add the hexanediamine sulfate liquor that step (2) obtains, fully stir, make to react completely, the pH value of neutralization back solution filters to isolate the solution and the moist CaSO that contain hexanediamine greater than 12
42H
2O;
(5), the solution that contains hexanediamine that obtains in the step (4) is steamed with vacuum follow the example of or extraction process obtains the thick solution of hexanediamine;
(6), the CaSO of humidity in the recycling step (4)
42H
2Hexanediamine among the O: with the CaSO of the humidity that obtains in the step (4)
42H
2O filters, and adopts the method for oven dry to obtain exsiccant CaSO
42H
2The thick solution of O and hexanediamine; Vacuum fluid bed dryer drying is adopted in oven dry, and temperature is lower than 160 ℃.In removal process, add Na
3PO
4, to prevent to form CaSO
4Fouling.Preferably will add Na
3PO
4Molar weight and CaSO
4Molar weight constitute 1: 2 relation.
(7), refining workshop section, the thick solution of hexanediamine that obtains in step (5) and the step (6) concentrated to make with extra care obtain the purified hexanediamine.
Embodiment 3
A kind of method of producing hexanodioic acid, hexanediamine with nylon-66 disaggregation, it comprises acidolysis workshop section, crystallisation by cooling workshop section, thick sour centrifugal station, recrystallization workshop section, in and workshop section and refining workshop section, each workshop section's step is:
(1), acidolysis workshop section, formic acid and water are added in the reactor, the concentration of control formic acid is 1%, add nylon-66 while heating then,, add sulfuric acid again the nylon-66 dissolving, under the condition of maintenance pressure, reacted 4～10 hours, obtain acid hydrolysis solution at 0.1～0.5MPa;
(2), thick sour centrifugal station and crystallisation by cooling workshop section, acid hydrolysis solution is entered crystallisation by cooling workshop section through coarse filter carries out crystallisation by cooling, separate obtaining thick adipic acid crystals and hexanediamine sulfate liquor then;
(3), refining workshop section, the thick adipic acid crystals that obtains in the step (2) decolour, recrystallization, oven dry obtain refined adipic acid;
(4), in and workshop section, in and add the milk of lime of capacity in the still, and then add the hexanediamine sulfate liquor that step (2) obtains, fully stir, make to react completely, the pH value of neutralization back solution filters to isolate the solution and the moist CaSO that contain hexanediamine greater than 12
42H
2O;
(5), the solution that contains hexanediamine that obtains in the step (4) is steamed with vacuum follow the example of or extraction process obtains the thick solution of hexanediamine;
(6), the CaSO of humidity in the recycling step (4)
42H
2Hexanediamine among the O: with the CaSO of the humidity that obtains in the step (4)
42H
2O filters, and adopts the method for oven dry to obtain exsiccant CaSO
42H
2The thick solution of O and hexanediamine; Vacuum fluid bed dryer drying is adopted in oven dry, and temperature is lower than 160 ℃.In removal process, add Na
3PO
4, to prevent to form CaSO
4Fouling.Preferably will add Na
3PO
4Molar weight and CaSO
4Molar weight constitute the relation of 1:2.
(7), refining workshop section, the thick solution of hexanediamine that obtains in step (5) and the step (6) concentrated to make with extra care obtain the purified hexanediamine.
At the background technology deficiency, the present invention has adopted and has utilized formic acid to dissolve earlier, does not adopt phosphoric acid or phosphoric acid salt, to improve its production efficiency.This be because, nylon solubilized (or swelling) is in formic acid, at this moment, it just be liquid/liquid reaction with the vitriolic reaction, and original nylon is that solid-liquid reacts with the vitriolic reaction, obvious, the former liquid/liquid speed of response will be reacted apparently higher than the latter's solid-liquid.Simultaneously, adopt high vacuum fluidized-bed exsiccant method of efficient and employing to add Na
3PO
4Can reach the purpose of conserve energy and minimizing fouling.
The present invention is to adopting formic acid dissolution process condition, vacuum fluid bed dryer operational condition and Na
3PO
4Add-on describe, other processing condition and traditional be similarly, please participate in traditional technology, just no longer be described on the details here.
Claims (5)
1, a kind of method of producing hexanodioic acid, hexanediamine with nylon-66 disaggregation, its include acidolysis workshop section, crystallisation by cooling workshop section, thick sour centrifugal station, recrystallization workshop section, in and workshop section and refining workshop section form, it is characterized in that each workshop section is as described below:
(1), acidolysis workshop section, formic acid and water are added in the reactor, add nylon-66 while heat then, nylon-66 is dissolved, add sulfuric acid again, under the condition of maintenance pressure, reacted 4～10 hours at 0.1～0.5MPa, obtain acid hydrolysis solution;
(2), crystallisation by cooling workshop section and thick sour centrifugal station, acid hydrolysis solution is entered crystallisation by cooling workshop section through strainer carries out crystallisation by cooling, separate obtaining thick adipic acid crystals and hexanediamine sulfate liquor then;
(3), recrystallization workshop section and refining workshop section, the thick adipic acid crystals that obtains in the step (2) decolour, recrystallization, oven dry obtain refined adipic acid;
(4), in and workshop section, in and add the milk of lime of capacity in the still, and then add the hexanediamine sulfate liquor that step (2) obtains, stir, make to react completely, the pH value of neutralization back solution filters to isolate the solution and the moist CaSO that contain hexanediamine greater than 12
42H
2O;
(5), refining workshop section, the solution that contains hexanediamine that obtains in the step (4) steamed with vacuum follows the example of or extraction process obtains the thick solution of hexanediamine; The CaSO of humidity in the recycling step (4)
42H
2Hexanediamine among the O is with the CaSO of the humidity that obtains in the step (4)
42H
2O filters, and adopts the method for oven dry to obtain exsiccant CaSO
42H
2The thick solution of O and hexanediamine; The thick solution of hexanediamine that obtains is mixed, concentrate the refining purified hexanediamine that obtains; In removal process, add simultaneously Na
3PO
4, to prevent to form CaSO
4Fouling.
2, a kind of method of producing hexanodioic acid, hexanediamine with nylon-66 disaggregation according to claim 1 is characterized in that the concentration of the formic acid described in step (1) the acidolysis workshop section is 1%～25%, is mass percent.
3, a kind of method of producing hexanodioic acid, hexanediamine with nylon-66 disaggregation according to claim 2 is characterized in that the concentration of the formic acid described in step (1) the acidolysis workshop section is 5%, is mass percent.
4, a kind of method of producing hexanodioic acid, hexanediamine with nylon-66 disaggregation according to claim 1 it is characterized in that the oven dry employing vacuum fluid bed dryer drying described in the refining workshop section of step (5), and temperature is lower than 160 ℃.
5, a kind of method of producing hexanodioic acid, hexanediamine with nylon-66 disaggregation according to claim 1 is characterized in that the adding Na described in the refining workshop section of step (5)
3PO
4Molar weight and CaSO
4Molar weight become 1: 2 relation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2007101564919A CN101423478B (en) | 2007-11-02 | 2007-11-02 | Method for producing hexane diacid and hexanediamine by using nylon-66 disaggregation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2007101564919A CN101423478B (en) | 2007-11-02 | 2007-11-02 | Method for producing hexane diacid and hexanediamine by using nylon-66 disaggregation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101423478A true CN101423478A (en) | 2009-05-06 |
| CN101423478B CN101423478B (en) | 2012-05-23 |
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ID=40614387
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2007101564919A Expired - Fee Related CN101423478B (en) | 2007-11-02 | 2007-11-02 | Method for producing hexane diacid and hexanediamine by using nylon-66 disaggregation |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102675084A (en) * | 2012-04-16 | 2012-09-19 | 周长秀 | A method for producing adipic acid by using waste polyurethane soles |
| CN107056625A (en) * | 2017-06-07 | 2017-08-18 | 巢湖市鼎盛渔具有限公司 | A kind of recovery method of polyamide 66 fishing net waste material |
| CN107056624A (en) * | 2017-04-19 | 2017-08-18 | 青岛科技大学 | A kind of alcoholysis recovery method of nylon 66 material |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1257880C (en) * | 2003-10-29 | 2006-05-31 | 宁波敏特尼龙工业有限公司 | Process for producing adipic acid and hexanediamine by depolymerization of nylon-66 |
-
2007
- 2007-11-02 CN CN2007101564919A patent/CN101423478B/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102675084A (en) * | 2012-04-16 | 2012-09-19 | 周长秀 | A method for producing adipic acid by using waste polyurethane soles |
| CN102675084B (en) * | 2012-04-16 | 2014-08-06 | 周长秀 | A method for producing adipic acid by using waste polyurethane soles |
| CN107056624A (en) * | 2017-04-19 | 2017-08-18 | 青岛科技大学 | A kind of alcoholysis recovery method of nylon 66 material |
| CN107056625A (en) * | 2017-06-07 | 2017-08-18 | 巢湖市鼎盛渔具有限公司 | A kind of recovery method of polyamide 66 fishing net waste material |
| CN107056625B (en) * | 2017-06-07 | 2019-04-23 | 巢湖市鼎盛渔具有限公司 | A kind of recovery method of -66 fishing net waste material of polyamide |
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| Publication number | Publication date |
|---|---|
| CN101423478B (en) | 2012-05-23 |
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