Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for recovering pentane diamine through steam stripping from water phase containing pentane diamine

A technology in the water phase of pentamethylenediamine, applied in organic chemistry, amino compound purification/separation, etc., can solve problems such as salt scaling, low extraction purity, and easy-to-coke pigments, etc., and achieve high-efficiency separation effects

Active Publication Date: 2019-10-25
NANJING UNIV OF TECH
View PDF16 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

But the recovery extraction method of present pentamethylenediamine, the removal of salt and pigment is mainly carried out by chromatographic method (for example patent CN108276292A, CN106861236A), experiment proves that this method is difficult to thoroughly remove salt and pigment, residual salt and pigment will affect Due to the continuity of the subsequent distillation, the salt is easy to scale on the tray, and the heat transfer is hindered, resulting in a sharp decrease in the recovery efficiency of the tray. At the same time, the eluent and the dicarboxylic acid form a salt and crystallize, and the residual inorganic salt in the product is high, which is very difficult. It is difficult to obtain high-quality nylon salt monomer
[0005] Another method for removing salt and pigment is mainly the extraction method, the patent CN106984061A butanol extraction method, the main problem is that the use of butanol will increase the cost of recovery, and water and butanol have certain miscibility, butanol extraction The extract contains water, and part of the salt will dissolve in the extract, so it is difficult to effectively remove the salt in the feed liquid
[0006] Patents CN107043333A and CN107043331A also disclose a method for extracting pentamethylenediamine, which uses a wiped-film evaporator or rake drying to evaporate the pentamethylenediamine in the system. However, the problem with this method is that the extraction purity is low. Pigments and inorganic salts are difficult to remove well
On the other hand, due to the existence of pigments and miscellaneous proteins in the system, it is easy to coke and produce new pigments in the later stage of evaporation, causing the decomposition of pentamethylenediamine

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0052] Take 150L of lysine sulfate fermented liquid, carry out catalytic conversion with reference to the catalytic decarboxylation technology disclosed in patent CN109402189A, obtain the conversion liquid of pentamethylenediamine salt, add NaOH or KOH to adjust alkali, adjust pH to 12.0, the The composition is as follows: the content of pentamethylenediamine is 120.0g / L, the T430nm light transmittance of the feed liquid is 20%, the total content of inorganic salt expressed as ash is 17%, and the remaining substances are other impurities and bacterial cells in the fermentation medium.

[0053] Take 10L of this material liquid and move it into a 20L stainless steel autoclave with a mechanical stirring device, and inject steam at 180°C for extraction. The part is connected with a glass condenser tube, and the pentamethylenediamine condensate is collected to obtain an aqueous solution of pentamethylenediamine. The temperature of the whole system is maintained at 175-185°C, the st...

Embodiment 2

[0055] Get 1.0L of pentamethylenediamine feed solution after alkali adjustment in Example 1, move it into a 2L stainless steel pressure-resistant kettle with a mechanical stirring device, pass into the air filtered through lime water and preheated to 180°C from the bottom of the liquid surface, The flow rate is 15L / h, and the temperature of the system is maintained at 175-185°C through the electric heating jacket. The condenser is used to fully condense at the top outlet of the autoclave, and the temperature of the refrigerant is -10°C. The extraction process was carried out for 4 hours, and 952mL of condensate was collected. The test results showed that the mass concentration of pentamethylenediamine was 122.2g / L, the extraction yield of pentamethylenediamine was 96.9%, and the T430nm was 96.2%. The purity is 97.3%, and the total inorganic salt content is 160 ppm expressed as ash.

Embodiment 3

[0057] Take three parts of 1.0L each of the pentamethylenediamine feed liquids after alkali adjustment in Example 1, respectively, and transfer them into 2L stainless steel pressure-resistant kettles respectively, and feed them from the bottom of the liquid surface, which have been preheated to 215~220°C, 145~ Nitrogen gas with a purity of 99.9% at 150°C and 100-105°C, with a flow rate of 15L / h, maintain the temperature of the system at 220°C, 150°C, and 100°C by heating or keeping warm, and use a heat exchanger at the top of the kettle to fully Condensation, the temperature of the refrigerant is -10°C. After passing through the condenser, the nitrogen is recovered, and the nitrogen is collected, compressed and recycled. The extraction process was carried out for 100min, and 960mL, 450mL, and 25mL of condensate were collected respectively. The test results showed that the mass concentrations of pentamethylenediamine were 123.1g / L, 60.2g / L, and 32.5g / L, respectively, and the ex...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a method for recovering pentane diamine through steam stripping from a water phase containing the pentane diamine. The method is characterized in that the water phase containing the pentane diamine is in direct contact with high temperature steam, after steam liquid equilibrium, a steam phase is recovered, steam containing the pentane diamine is obtained or an aqueous solution containing the pentane diamine is obtained after condensation, and then purification is further conducted to obtain pure pentane diamine or pentane diamine dicarboxylate. The method has the beneficial effects that one-step separation of the pentane diamine from salt, pigment and protein can be realized, chromatographic purity of a obtained dpentane diamine solution can be up to 99.5%, operability and continuity of preparation of the pure pentane diamine in the subsequent distillation process are advantageous, or for preparation of nylon 5X monomer salt by salifying crystallization, the pressure of crystallization can be reduced, and a high purity crystal is obtained. According to the method, the pentane diamine can also be recovered from waste liquid containing the pentane diamine produced in the preparation process of the pentane diamine by a biological method, the extraction process is simple, and the extraction yield can be up to 98%.

Description

technical field [0001] The technology relates to the field of recovery of chemical products, in particular to a method for stripping and recovering pentamethylenediamine from an aqueous phase containing pentamethylenediamine. Background technique [0002] At present, the main varieties of the polyamide market in the world are polyamide 6 and polyamide 66, which are produced by chemical methods using petroleum as raw materials, and the raw materials are poor in sustainability and environmental friendliness. Hexamethylenediamine, the raw material monomer for the synthesis of polyamide 66, has been monopolized by a few foreign companies for a long time. China is completely dependent on imports. There has been no obvious breakthrough until now, which greatly limits the development of China's polyamide industry. 1,5-Pentanediamine can be produced from biomass through green bio-methods. Pentamethylenediamine and adipic acid can be polymerized to obtain nylon 56, which is considere...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): C07C209/86C07C209/84C07C211/09
CPCC07C209/86C07C209/84C07C211/09
Inventor 应汉杰杨朋朋沈涛林晨光温庆仕吴菁岚陈勇朱晨杰王骏之欧阳平凯
Owner NANJING UNIV OF TECH