正硅酸乙酯为硅源制备吸附分离液蜡的5A分子筛的研究.pdf

石油化工
2014年第43卷第6期
PETROCHEMICAL TECHNOLOGY
正硅酸乙酯为硅源制备吸附分离
液蜡的5A分子筛的研究
楚迎亚,陈乐,陈群
(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)
[摘要]以正硅酸乙酯为硅源,采用水热法制备5A分子筛,考察晶化时间、晶化温度及无水乙醇的添加量对分子筛晶体结构
的影响,采用XRD、SEM、N2吸附-脱附等測试方法进行表征,并将制备的5A分子筛用于吸附正构烷烃。实验结果表明,制
备5A分子筛的优化条件为:碱水比ァ(Na2O):n(H2O)=1:50、晶化时间24h、晶化温度90℃、无水乙醇添加量12%(p),该
条件下制备的5A分子筛在吸附温度为30℃时对正癸烷、正十五烷的饱和吸附量分别为0.538,0.647g/g;无水乙醇作为共溶
剂,能加快正硅酸乙酯的水解,同时减小分子筛晶体尺寸,但添加过量将导致晶体尺寸不均匀,影响其吸附性能;分子筛晶
体的微观结构对静态饱和吸附量和吸附速率的影响很大,添加12%(q)的无水乙醇、以正硅酸乙酯为硅源制备的5A分子筛存
在多孔结构,有利于正构烷烃分子的扩散,饱和吸附量增加。
关键词]正硅酸乙酯;5A分子筛;无水乙醇;液体石蜡;吸附分离
文章编号]1000-8144(2014)06-0631-06
中图分类号]TQ424.25
[文献标志码]A
Prepaation of A Moleular Sieve from Ethyl Orthosilicate for Separation of Liquid Parain
Chu Yingya, Chen Le, Chen Oun
( Key Laboratory of Fine Petrochemical Engineering, School of Petrochemical Engineering, Changzhou University
Changzhou Jiangsu 213 164, China
I Abstract J A molecular sieves were synthesized from ethyl orthosilicate by a hydrothermal method
and used in the adsorption of liquid paraffin. The effects of crystallization time, crystallization
temperature and absolute ethanol dosage on the crystal structures of the molecular sieves were
investigated. The 5A molecular sieves were characterized by means of XRD, SEM and BET. The
results showed that under the optimum conditions of absolute ethanol dosage 12%( ) crystallization
time 24 h and crystallization temperature 90"C, the adsorptivity of the 5A molecular sieve was the
best with the static adsorption capacities of 0.538 g/g for n-decane and 0.647 g/g for n-pentadecane
Absolute ethanol as a cosolvent can accelerate the hydrolysis of ethyl orthosilicate and reduce the
crystal grain size, but too much addition of absolute ethanol will lead to uneven crystal size and
reduce the adsorptivity. The effects of the crystal microstructure on the static saturated adsorptivity
and adsorption rate of the 5A molecular sieve are large. The 5A molecular sieve with absolute ethanol
dosage 12%( )has vesicular structure, which is beneficial to the diffusion of alkanes, so its static
saturated adsorptivity is larger
I Keywords ethyl orthosilicate; 5A molecular sieve; absolute ethanol; liquid paraffin; adsorption
separation
据纽约 Pound Ridgel的化学咨询公司调査,使用UOP公司的ADS型5A分子筛吸附剂。1998
1990-2010年全球烷基苯洗涤用品的需求量由2.5〔收稿日期]2013-12-17:[修改稿日期】2014-03-09。
M增至3.5Mt,相应地对高纯度液蜡的需求量将由[作者筒介楚迎亚(1990-),女,河南省驻马店市人,硕士
,电话15951201307,电邮630065073②q9.com。联系人:陈
24M增至30M以上リ。20世纪0年代末以来、分群电郎。mnpm
子筛脱蜡技术主要采用UOP公司的 Melox工艺2
[基金项目]江苏省自然科学青年基金项目(BK2013025!)。