Method for synthesizing calcium epoxy succinate suspension and method for producing L-(+)-tartaric acid

Abstract

The invention discloses a method for synthesizing calcium cis-epoxy succinate. According to the method, maleic anhydride, calcium carbonate, and hydrogen peroxide are adopted for a reaction in the presence of sodium tungstate as a catalyst, and calcium hydrate is used for adjusting the pH value. The invention further discloses a method for producing L-(+)-tartaric acid. According to the method, calcium cis-epoxy succinate is used for producing calcium L-(+)-tartrate in the presence of an enzyme as a catalyst; a solid coarse calcium L-(+)-tartrate product is separated; sulfuric acid is adopted for acidolysis; separation is carried out to remove calcium sulfate; and purification is carried out to produce the final L-(+)-tartaric acid product. Instead of a current sodium cis-epoxy succinate conversion process, according to the method, calcium L-(+)-tartrate is directly produced, so that a calcium salt precipitation operating unit is saved; discharge of sodium ions is reduced; and consumption of raw materials is decreased. The methods have significant industrial application value and environmental benefit.

Description

technical field [0001] The invention belongs to the field of biocatalytic preparation of organic acids, in particular to a method for synthesizing calcium epoxysuccinate suspension and a method for producing L-(+)-tartaric acid using the suspension. Background technique [0002] L-(+)-tartaric acid is a natural organic acid, which is an important food additive and chemical raw material. The traditional enzymatic conversion to produce L-(+)-tartaric acid generally uses cis-epoxysuccinate sodium as the catalytic substrate, and under the catalysis of cis-epoxysuccinate hydrolase (ESH), L-(+) -sodium tartrate, and then use the calcium salt method to extract L-(+)-tartaric acid (that is, add a calcium neutralizer to the conversion solution containing L-(+)-sodium tartrate to generate L-(+)- Calcium tartrate, after repeated crystallization and washing, add sulfuric acid acid hydrolysis to extract L-(+)-tartaric acid, and decolorize with activated carbon, and remove impurity ions ...

AI Technical Summary

Problems solved by technology

In order to overcome the defects such as low batch conversion efficiency of traditional cis-calcium epoxysuccinate, the present invention adopts the mode of continuous feeding, and adds sodium sulfate co-solvent during the conversion process of cis-calcium epoxysuccinate, so that in the reaction system The various ions are in the dynamic equilibrium state of "cis-calcium epoxysuccinate-calcium sulfate-sodium cis-epoxysuccinate-sodium sulfate", thereby improving the conversion efficiency of calcium cis-epoxysuccinate and L-( +)-Tartaric acid production efficiency

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