The New Process Of Continuous Removal Of Cation And Anion In Acid Hydrolysis Solution Of Citric Acid

Citric acid is an important organic acid, widely used in various fields. The production process of citric acid is mature. At present, the method of calcium and ion exchange are mostly used for the production of citric acid at home and abroad. The method of calcium and ion exchange for the production of citric acid is used to remove the anions and cations with the fixed bed in the ion exchange process, to purify the citric acid solution. Although the process of purifying citric acid is mature, but it has some disadvantages such as large labor intensity, covering a large area, low utilization rate of equipment and resin, the higher consumption of deionized water and regenerating agent, resulting in high production cost. So this paper presents the new process of continuous removal of cation and anion in acid hydrolysis solution of citric acid.Firstly this paper studies the law of single column removal of cation and anion at different flow rates. Focus on the relationship between the resin adsorption curve, adsorption time and washing and recycling law at different flow rates. Through the experimental research, this paper summarizes the relationship between flow rates, the resin adsorption time, exchange zone and resin content as removing the anions and cations of citric acid solution.According to the research results of single column test, using ISEP moving bed device, study on the process of continuous removal of cation and anion in citric acid hydrolysis solution. The process is based on a single column test, then studying the pilot test and industrial test.The pilot test and industrial test show that the new process of continuous removal of cation and anion in citric acid hydrolysis is feasible. The process has many advantages, such as small footprint devices, stable quality of citric acid ion exchange liquid, small fluctuation, high utilization rate of equipment and resin, production automation, high yield, low treatment cost. Relatively fixed bed intermittent ion exchange process, the acid-base regenerative agent consumption of the new technology reduced about30%, water consumption and waste emissions decreased by about70%, the yield increased about1.0-2.0%.