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

Method for recovering imidazole from imidazole hydrochloride wastewater

A technology of imidazole hydrochloride and waste water, applied in the direction of organic chemistry, can solve the problems of increased cost and difficulty of imidazole recovery, easy blockage of distillation pipelines, complicated operation, etc., to improve the operating environment of employees, reduce environmental pollution, and simple operation Effect

Active Publication Date: 2021-08-27
SHANDONG HUIHAI PHARMA & CHEM
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] As an important intermediate in organic synthesis, imidazole is widely used in the fields of medicine, pesticides, special materials, etc. Cause the cost and difficulty of recovering imidazole from imidazole hydrochloride wastewater to increase greatly
[0003]In the existing recovery method, the main method is to adjust the imidazole hydrochloride wastewater to be alkaline with an organic base, then add a large amount of organic solvent to distill with water, and distill to a molten state The solid is heated up in a vacuum state to reach the boiling point of imidazole, and the imidazole is distilled. Due to the high boiling point of imidazole at room temperature, and it is easy to desublimate, it is easy to block the distillation pipeline, and it is quite complicated to operate under vacuum conditions. Distillation to extract the original height of imidazole

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

[0024] Add 72g of imidazole hydrochloride wastewater (containing about 46g of imidazole hydrochloride) into a 500ml four-neck flask, add 30% sodium hydroxide solution dropwise at room temperature, add 59g dropwise, adjust the pH to 11, then concentrate the water under reduced pressure, After concentrating with a small amount of water, add 72g of toluene with water. Toluene is preferably used with a purity of 99% or more. After evaporating the water, add 144g of toluene, stir to raise the temperature to 80°C, stir for 30min, then cool down to 60°C, perform hot filtration, and remove The solids in the system were then cooled slowly at room temperature, filtered after cooling down to 20°C to obtain imidazole, and weighed to obtain 28.1 g of imidazole after drying. After testing, the purity is 98.5%, and the content reaches 97.8%, which meets the product quality standard; after calculation, the yield reaches 93.67%.

Embodiment 2

[0026] Add 80g of imidazole hydrochloride wastewater (containing about 46g of imidazole hydrochloride) into a 500ml four-neck flask, add 15% sodium carbonate solution dropwise at room temperature, add 130g dropwise, adjust the pH to 11, then concentrate the water under reduced pressure, concentrate After containing a small amount of water, add 80g of toluene with water, evaporate the water, add 160g of toluene, stir to raise the temperature to 80°C, stir for 30min, then cool down to 60°C, perform hot filtration to remove the solids in the system, and then slowly cool down at room temperature , cooled to 20°C and then filtered to obtain imidazole, which was weighed to obtain 28.6 g of imidazole after drying. After testing, the purity is 98.8%, and the content reaches 98.2%, which meets the product quality standard; after calculation, the yield reaches 95.33%.

Embodiment 3

[0028] Add 82g of imidazole hydrochloride wastewater (containing about 46g of imidazole hydrochloride) into a 500ml four-neck flask, add 30% sodium hydroxide solution dropwise at room temperature, add 134g dropwise, adjust the pH to 11, then concentrate the water under reduced pressure, After concentrating with a small amount of water, add 82g of toluene with water, evaporate the water, add 164g of toluene, stir to raise the temperature to 70°C, stir for 30min, then cool down to 50°C, perform hot filtration, remove the solids in the system, and then slowly After cooling down to 20°C, filter to obtain imidazole, and weigh 28.5 g of imidazole after drying. After testing, the purity is 98.4%, and the content reaches 98%, which meets the product quality standard; after calculation, the yield reaches 95%.

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 imidazole from imidazole hydrochloride wastewater, which comprises the following steps: adjusting the pH value of a system by using liquid caustic soda or a sodium carbonate solution, concentrating solvent water under reduced pressure, carrying water by using toluene, and keeping the heating temperature of the wastewater at 70-80 DEG C in the whole recovery process. Compared with the prior art wherein high temperature distillation is adopted, and an imidazole boiling point is needed, the method has the advantages: the operation environment of staff is greatly improved, the environmental pollution is reduced, the operation is simpler, the production cost is lower, finally, imidazole is collected through hot filtration and suction filtration, and compared with a high-temperature distillation mode, the recovery rate and the purity are greatly improved.

Description

technical field [0001] The invention relates to the technical field of imidazole recovery, in particular to a method for recovering imidazole from imidazole hydrochloride wastewater. Background technique [0002] As an important intermediate in organic synthesis, imidazole is widely used in the fields of medicine, pesticides, and special materials. Because of its extremely water-soluble characteristics, it is very costly and difficult to recover imidazole from imidazole hydrochloride wastewater. Increase. [0003] In the existing recovery method, mainly adjust the imidazole hydrochloride waste water to be alkaline with an organic base, then add a large amount of organic solvent to distill with water, distill to the solid in the leftover molten state, heat up in a vacuum state, and reach the boiling point of imidazole. Imidazole distillation, due to the high boiling point of imidazole at room temperature, is easy to desublimate, and is easy to block the distillation pipeline...

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
Patent Type & Authority Applications(China)
IPC IPC(8): C07D233/58
CPCC07D233/58
Inventor 付德修郑庚修姜福元赵攀峰张路军王磊
Owner SHANDONG HUIHAI PHARMA & CHEM