【摘要】 利用浅床实验法研究查明了钠型斜发沸石Na~+–K~+离子交换过程以液膜扩散为主的控制机理,依据传质膜理论,推导出液膜控制下的离子交换传质速率模型,并测定了离子交换动力力学曲线和过程传质系数。研究结果表明:钠型斜发沸石Na~+–K~+离子交换速率与溶液流速、温度和溶液的K+浓度成正比,与溶液粘度和沸石粒径成反比,过程总传质系数的模型计算值与实验值拟和较好。更多还原

【Abstract】 The control mechanism of Na+—K+ ion-exchange on Na-clinoptilolite, which relies mainly on liquid film diffusion, has been found out by the shallow-bed method. Basing on the mass transfer theory, the mass transfer rate model of ion exchange under liquid film control was derived, and the kinetic curves of ion exchange and total mass transfer coefficient were determined. The experimental results showed that Na+—K+ ion exchange rate is directly proportional to solution flow rate, temperature and K+ concentration, and inversely to solution viscosity and the size of zeolite particles. The value of total mass transfer coefficient calculated by model fitted experimental results very well. The results provide the theory foundation for further development of potassium extraction from seawater by clinoptilolite.更多还原