碱金属卤化物与NaA分子筛之间的固态离子交换反应

Solid-state Ion Exchange between Halides and Zeolites

在低于碱金属卤化物熔点的温度下热处理碱金属卤化物和脱水NaA分子筛干混样品时,一部分分散到分子筛内孔的金属离子能够与脱水分子筛进行程度不同的固态离子交换反应,生成的非挥发性NaCl产物将扩散到分子筛笼外单独结晶或与剩余的原卤化物形成固溶体.热处理温度愈高,离子交换度愈大;在一定温度下热处理干混样品,存在最大离子交换度.

Solid-state ion exchange of Na^+ in dehydrated NaA zeolite for K^+ or Li^+ can be conducted to a high degree by heating the mixture of alkali-halide and NaA zeolite at elevated temperature below the melting point of the alkali-halide. A part of the reactant product NaCl diffuses out of zeolite pores and Crystallizes itself or with residual former halides. The higher the elevated temperature is the greater the ion exchange degree is. There is the largest ion exchange degree at a heating temperature.