New method for synthetizing polyaspartic acid by fumaric acid

Abstract

The invention discloses a method for synthetizing polyaspartic acid by fumaric acid, which comprises the following steps of (1) fermenting and synthetizing L-polyaspartic acid by taking the fumaric acid and ammonia as raw materials and taking escherichia coli as a catalyst, wherein the molar ratio of the fumaric acid to the ammonia is 1:1; the dosage of the escherichia coli is 0.3-0.5 permillage of the total weight of the raw materials, the fermenting temperature is 36-40 DEG C and the fermenting time is 24 h; and (2) continuously carrying out polycondensation for 10-60min at the temperature of 180-250 DEG C by taking the rough L-polyaspartic acid which is not discolored and obtained in the step (1) as raw material to synthetize the polyaspartic acid. The method can realize the large scale and economization of the production of the polyaspartic acid.

Description

technical field

[0001] The present invention relates to a kind of fumaric acid and NH 3 As raw material, L-aspartic acid is obtained by fermentation method, and the crude product L-aspartic acid is used for large-scale production technology of polyaspartic acid by disc continuous reaction polymerization. Background technique

[0002] Polyaspartic acid is a polymeric amino acid, artificially synthesized polypeptide, a soluble polymer, non-toxic, non-polluting, biodegradable and environmentally friendly product, which has a wide range of uses, and is widely used in plant nutrition and industrial dispersants, water Treatment agents, pesticides, green ecological additives, etc.

[0003] As we all know, the method of synthesizing polyaspartic acid from L-aspartic acid mostly adopts intermittent polycondensation method, which has long polycondensation time, low thermal efficiency, product pulverization, product loading and unloading pollutes the working environment, small product...