凹凸棒土粘结剂对13X分子筛吸附性能的促进作用

以凹凸棒土为粘结剂制备了13X分子筛吸附剂.研究了其孔结构、表面电性和对水、CO2和N2分子的吸附性能,并与高岭土为粘结剂的同类吸附剂进行了比较.结果表明,凹凸棒土发达的孔隙结构、大的比表面和表面负电性质有利于其吸附容量的改善,而13X/凹凸棒土中丰富的中孔促进了其对CO2的吸附速率.另外由CO2吸附热力学分析可知,CO2在13X/凹凸棒土上具有较低的吸附热,结果将有利于其在吸附剂上的脱附.

IMPROVEMENT EFFECT OF ATTAPULGITE BINDER ON THE ADSORPTION PROPERTIES OF ZEOLITE 13X ADSORBENT

Shaped 13X zeolite adsorbent was prepared by using attapulgite binder, and the effect of binder on the adsorption properties of shaped zeolite was investigated. The adsorptions of H2O, CO2 and N2 on shaped zeolite bonded with attapulgite show higher adsorption capacity and higher adsorption rate compared with that with kaolin. The characterizations of N2 adsorption at 77K and isoelectric point measurement display that the higher pore volume, large surface area and surface negative charge property of attapulgite can be responsible for the higher adsorption capacity of resulting shaped zeolite, and relative higher adsorption rate for CO2 on 13X/attapulgite is resulted from the existence of more abundant mesopore in adsorbent. Moreover, the lower adsorption heat for CO2 on 13X/attapulgite, reflecting the weaker interaction between CO2 and adsorbent, is beneficial to the desorption CO2.