摘要
用真空重量法研究了水在3A分子筛上的吸附行为,得到不同温度(373.15,393.15,423.15,463.15,523.15K)下的吸附等温线,分别采用Freundlich模型、Langmuir模型以及Langmuir-Freundlich模型对实验数据进行拟合,得到吸附量与温度的关联式。讨论了模型各参数与温度的关系。通过改变分子筛粒径验证了吸附过程为晶体扩散控制,采用程序升温脱附法得到不同温度下的扩散系数,找出了校正扩散系数随温度和吸附质浓度的变化规律。
Using method of TG, the adsorption of water on 3A molecular sieve had been investigated. The equilibrium experiments were conducted at 373.15,393.15,423.15,463.15,523.15 K and pressures up to 10 kPa. Fitting the equilibrium isotherms by Langmuir, Freundlich and Langmuir - Freundlich models separately, the consequent equilibrium isotherms verified that the adsorption complied with Langmuir-Freundlich model. Relationship between parameters of the model and temperature was discussed. Test results of on 3A molecular sieve with various granular sizes proved that intracrystalline diffusion was the rate -control step of adsorption. The regularity of variation of corrected diffusion coefficients with temperature and concentration were found out.
出处
《石油化工》
CAS
CSCD
北大核心
2004年第10期932-936,共5页
Petrochemical Technology
关键词
分子筛
吸附等温线
晶体扩散
程序升温脱附
水
<Keyword>molecular sieve
equilibrium isotherms
intracrystalline diffusion
temperature - programmed desorption
water
