Novel method for preparing vanillin by lignin

Abstract

The invention relates to a novel method for preparing vanillin by lignin, and relates to the chemical technical field. The novel method is as follows: selecting wood fragments and cleaning, treating for 2 minutes by adopting vapor of 220 DEG C, washing for twice to three times by adopting water of 100 DEG C, then, filtering, treating solid insolubles by adopting sodium hydroxide liquor with PH of 3, filtering again, treating filtrate for 10 minutes by sulfuric acid with PH of 2 in water at a temperature of 80-90 DEG C, continuously filtering to obtain lignin which is not easy to acidified, adding the login and sodium hydroxide liquor in a proportion of 1:10 into a high-pressure kettle, adding copper oxide, introducing chloride gas, controlling pressure to 1.4 MPa, stirring, heating to 160-180 DEG C, carrying out constant-temperature reaction for 2-4 minutes, removing copper oxide by filtering after the reaction is ended, acidifying mother liquor to obtain crude vanillin, placing into a crystallization kettle to crystallize and dry to obtain a finished product, and then packaging and storing. The novel method disclosed by the invention has beneficial effects that the preparation method is simple and convenient, environmentally friendly and pollution-free, less in equipment investment, high in purity and convenient to operate, materials are easily available; and the prepared vanillin is good in using effect, safe and reliable.

Description

technical field [0001] The invention relates to the technical field of chemical industry, in particular to a novel method for preparing vanillin from lignin. Background technique [0002] Vanillin, also known as vanillin, is a widely used edible spice, which can be found in the seeds of vanilla or artificially synthesized, and has a strong milky aroma. It is widely used in various flavored foods that need to increase the milk flavor, such as cakes, cold drinks, chocolate, candy; it can also be used in soap, toothpaste, perfume, rubber, plastic, and pharmaceuticals. Vanillin is one of the important food spices, and it is a food flavoring agent. It has vanilla bean aroma and strong milky aroma. It is an indispensable and important raw material in the food additive industry. It is widely used in various needs to increase milky aroma. Flavoring food, such as cakes, cold drinks, chocolate, candy, biscuits, instant noodles, bread and tobacco, flavored wine, toothpaste, soap, perf...

AI Technical Summary

Problems solved by technology

From 1993 to 2002, the average annual growth rate of China's vanillin export volume was 12%. The traditional production process of vanillin is relatively complicated, and the purity of production is relatively low, which is difficult to meet the needs of human beings.