Preparation of Complex of L-Histidine Calcium with Cation Exchange Resin

The complex of L-histidine calcium was prepared with D151 and 110 cation exchange resins.The calcium exchange capacities and exchange kinetic curves at 26 ℃ with the resins were measured.And the effects of temperature, molar ratio of NaOH to L-histidine, concentration of L-histidine, and quantity of resin on calcium exchange process were determined.The results show that calcium exchange capacities of D151 and 110 resins were 1.12 and 2.59 mmol/g, the exchange process was quick, and calcium exchange process exothermic, so industrial process could be carried out at room temperature or low temperature.The proper molar ratio of NaOH to L-histidine was(1～1.25):1, the proper concentration and resin quantity of D151 cation exchange resin were 0.46 mol/L and 0.125 g/mL or so, and those of 110 resin were 0.4 mol/L and 0.15 g/mL or so.