New purpose of corn core

Abstract

The invention relates to a new use of corn core, in particular to the application of the corn core in the citric acid preparation with a fermentation method. The preparation method comprises acidolysis, enzymolysis, fermentation, separation, and post treatment. The acid hydrolysis, namely, the corn core is hydrolyzed in 0.5 to 1.2 percent of dilute sulfuric acid solution at the temperature of 90 to 140 DEG C for 1.0 to 3.5 hours, and is separated and cleaned to obtain acidolysis sludge, the enzymolysis, namely, enzyme hydrolysis is performed to the acidolysis sludge with cellulase and cellobiase, so as to convert the cellulose into glucose, the glucose is separated and cleaned, and then enzymolysis liquid containing glucose is fermented with known spergillus niger, so as to convert the glucose into citric acid, and finally a monohydrate citric acid crystal with the purity being more than or equal to 99.8 percent can be obtained through the post treatment. About 5 to 7 tons of corn core are consumed for producing 1 ton of citric acid at a time, and therefore the raw material cost of the citric acid is greatly reduced.

Description

1. Technical field [0001] The invention relates to a comprehensive utilization of agricultural waste, in particular to a new application for preparing citric acid by fermenting corn cobs. 2. Background technology [0002] Citric acid is also known as citric acid, its English name is citric acid, and its chemical name is 3-hydroxy-3-carboxyglutaric acid. Appearance Colorless translucent crystal, or white granule, or white crystalline powder. The crystalline form of citric acid is different due to different crystallization conditions. There is anhydrous citric acid C 6 h 8 o 7 , there is also citric acid 2C containing crystal water 6 h 8 o 7 ·H 2 O, C 6 h 8 o 7 ·H 2 O or C 6 h 8 o 7 2H 2 O. Commercial citric acid is mainly anhydrous citric acid and monohydrate citric acid. [0003] The traditional production method of citric acid in my country is to use starchy agricultural products as raw materials. The applicant once pioneered the method of preparing citric...

AI Technical Summary

Problems solved by technology

[0004] The annual output of corn in my country reaches 123 million tons. According to the calculation of the grain cob ratio of 1:0.25, the corn cob is also produced about 30 million tons per year. It is a renewable resource with great potential, especially as a raw material for renewable energy and chemical products, which has been widely valued. , but at present, except for a small part used as raw material for furfural production, most of them are not utilized