Citric acid is a kind of important organic acid, also known as folic acid, and often contain a molecular crystal water, odourless, has a strong acid, soluble in water. Crystallization in control the temperature of the appropriate anhydrous citric acid can be obtained. In the industry, food industry. Application of ion exchange resins as adsorbent, by electrostatic attraction brought solution of the adsorption of opposite electric charge on the ion exchange resin, and then use the appropriate eluent adsorbate from elution ion exchange resin, so as to achieve the purpose of separation and purification. Suzhou Bojie Resin Techonology Co, Ltd Provide citric acid resin, isolation and purification of high exchange capacity, adsorption capacity is large, regeneration is convenient, good mechanical strength.