利用磷肥副产含氟硅胶制δ型层状结晶二硅酸钠

磷肥副产含氟硅胶经氨洗、水洗至中性后，与片状烧碱反应，制得模数为2．0的水玻璃，然后加3％的KCI作晶型转化剂，经煅烧制备δ型层状结晶二硅酸钠。实验得出制取中间产物水玻璃的最佳工艺条件是：反应温度720-800℃、反应时间40min；水玻璃煅烧制d型层状结晶二硅酸钠的最佳工艺条件是：煅烧保温温度600℃、保温时间30．50min。在最佳条件下，可得到钙离子交换量大于4A沸石的优质δ型层状结晶二硅酸钠。

Preparation of δ-Type Laminated Crystalline Sodium Silicate Using Byproduct Silica Gel Containing Fluorine from Phosphate Fertilizer Industry

δ - Type laminated crystalline sodium silicate was prepared by calcinating sodium silicate which was obtained by the reaction of flake caustic alkali and the byproduct silica gel containing fluorine from phosphate fertilizer industry. The optimum conditions were determined： the middle - product sodium silicate was obtained under reaction temperature 720 - 800 ℃ and reaction time 40 min, and the object product δ - type laminated crystalline sodium silicate was obtained by calcinating middle - product at 600 ℃ for 30 - 50 min. The calcium ion exchange capaeity of the object product prepared under the optimum conditions was larger than that of 4A zeolite.