导向剂法合成吸附分离液蜡的5A分子筛的研究  

PREPARATION OF 5A MOLECULAR SIEVES BY HYDROTHERMAL METHOD WITH GUIDING AGENT FOR SEPARATION OF LIQUID PARAFFIN

作　　者：楚迎亚 陈乐[1] 陈群[1] 

机构地区：[1]常州大学石油化工学院,江苏省精细石油化工重点实验室,江苏常州213164

出　　处：《离子交换与吸附》2013年第6期496-504,共9页Ion Exchange and Adsorption

基　　金：江苏省自然科学基金青年基金项目(No.BK20130251);国家自然科学基金(No.21201026)

摘　　要：在水热法合成5A分子筛的过程中添加结晶导向剂,通过考察导向剂的老化时间、加入时间、添加量,使得5A分子筛具有较优的吸附液体石蜡的能力。实验结果表明,在4A分子筛开始老化前加入8%(相对于水的体积含量)老化24h的导向剂,制得的5A分子筛试样吸附正癸烷和正十五烷的静态饱和吸附量最大,分别为0.371g/g和0.309g/g。表征结果显示,导向剂的添加量对5A分子筛晶体尺寸有一定的影响,添加量的增加会使样品的晶粒变小,但过高的添加量会使分子筛的晶型发生改变,生成其他晶型的分子筛,从而影响A型分子筛的纯度;晶体的孔结构对静态饱和吸附量和吸附速率影响较大,导向剂添加量为8%的5A分子筛试样B的平均孔径最大,既存在微孔又有较多的中孔,具有较宽的孔径分布,有利于减小长链烷烃分子在吸附剂内的扩散阻力,其对正癸烷和正十五烷的的静态饱和吸附量最高。5A molecular sieves were synthesized by hydrothermal method with guiding agent and used in the adsorption of liquid paraffin. A series of experiments were carried out to investigate the effect of aging times, addition time and addition amount of guiding agent on the performance of 5A molecular sieves. The results showed that the maximum static adsorption capacities of 0.371g/g for n-decaneand and 0.309gig for n-pentadecane were obtained with the 5A molecular sieves, which were synthesized with 8% （relative to the volume of water） of guiding agent added and 24h of aging time. The characterization results showed that the main influencing factor on crystal size of 5A molecular sieves was the addition amount of guiding agent, Higher amount of agent could lead to smaller size of crystal grains, but too much addition amount will change the crystal type and affect the purity of A-type molecular sieves. The crystal microstructures showed significant influence on the static saturated adsorption capacity and adsorption rate of n-decaneand and n-pentadecane on 5A molecular sieves. Micro- and appropriate meso-pores were introduced into the 5A molecular sieves by 8% of guiding agent added, so that the pore size distribution was wider and the molecular diffusion resistance of the long chain alkanes was effectively reduced. Finally, higher static saturated adsorption capacity was obtained.

关 键 词：5A分子筛 导向剂 液体石蜡 吸附分离 

分 类 号：TQ424.2[化学工程]