Potassium citrate mother liquor deironing purification process

Abstract

The invention relates to a potassium citrate mother liquor deironing purification process, which comprises the following specific steps: (1) adding pure water into potassium citrate last mother liquorto dilute the potassium citrate last mother liquor, and then heating to 60-80 DEG C to obtain a solution A; (2) adding citric acid into the solution A, and adjusting the pH value to 6.5-8.0 to obtaina solution B; (3) adding a certain amount of hydrogen peroxide into the solution B, and oxidizing ferrous iron in the solution B into ferric iron to obtain a solution C; (4) enabling the solution C to pass through an ion exchange column filled with cationic resin according to the flow rate of 150L / h-200L / h to obtain a solution D; (5) enabling the solution D to pass through an activated carbon column at the flow rate of 150L / h-200L / h, and removing readily carbonizable compounds to obtain a solution E; and (6) carrying out evaporative crystallization, centrifugal separation and drying on the solution E to obtain a potassium citrate product. According to the potassium citrate mother liquor purification process, iron and readily carbonizable compounds in the potassium citrate mother liquor can be effectively removed, the yield of potassium citrate is increased by about 5%, zero emission of the potassium citrate mother liquor is achieved, and economic benefits and environmental protectionbenefits are remarkable.

Description

technical field [0001] The invention relates to the technical field of food additives, in particular to a process for iron removal and purification of potassium citrate mother liquor. Background technique [0002] Potassium citrate is colorless crystal or white crystalline powder, easily soluble in water, tastes salty and cool. It can be used as buffering agent, chelating agent, stabilizer, antioxidant, emulsifier, etc. in the food industry, and can be used as an anticoagulant, hypokalemia and alkaline urine treatment in the pharmaceutical industry. In recent years, its demand volume has been growing steadily. [0003] The production process of potassium citrate is to dissolve citric acid in water and potassium hydroxide solution for neutralization reaction to generate potassium citrate solution. The potassium citrate solution obtained by the reaction is finely filtered, evaporated and crystallized, centrifuged and dried to obtain the finished product of potassium citrate....

AI Technical Summary

Problems solved by technology

[0004] In the process of industrial potassium citrate production, a large amount of potassium citrate final mother liquor will be produced. This part of the mother liquor contains high iron and other metal ions, a small amount of easily carbonized substances such as protein colloids and organic impurities, making citric acid The color of the potassium mother liquor becomes darker and the viscosity becomes larger, and the qualified potassium citrate product can no longer be crystallized, and it can only be used as waste liquid to enter the sewage treatment system

This not only causes a huge waste of resources and reduces the yield of potassium citrate products, but also invests in special sewage treatment equipment, which costs a lot of treatment costs

After research, the main factors affecting the quality of lemon potassium are iron and easy carbon compounds in the mother liquor. When the iron ion content in potassium citrate is greater than 10ppm, the product will turn yellow, the light transmittance will be significantly reduced, and the product quality will be significantly reduced.