摘要
采用乙醇-盐酸萃取辅助高温焙烧法(萃取-焙烧两步法)脱除模板剂(聚环氧乙烷(PEO)-聚环氧丙烷(PPO)-聚环氧乙烷聚合物,P123),经金属Al原位掺杂改性,水热晶化法合成了一种具有蠕虫状形貌的Al-KIT-6介孔分子筛,使用浸渍法制备了不同镍负载量的Ni/Al-KIT-6金属-酸双功能催化剂。采用XRD、N2吸附-脱附、NH_(3)-TPD、IR、SEM和TEM等表征手段对Al-KIT-6分子筛及催化剂样品进行物化性能分析,并以正庚烷为反应原料,对Ni/Al-KIT-6催化剂样品进行正庚烷异构化反应性能评价。结果表明:采用萃取-焙烧两步法可以有效脱除模板剂,相比于常规焙烧法和萃取法脱除模板剂制备的分子筛样品,萃取-焙烧两步法脱除模板剂制备的KIT-6分子筛样品具有更大的比表面积、孔体积,同时孔径分布更加均一;分子筛骨架中掺杂Al原子增加了分子筛的酸性;在氢气流速30 mL/min、重时空速7.6 h^(-1)、反应温度190℃、反应时间3 h,常压的条件下,镍负载质量分数为5%的Ni/Al-KIT-6催化剂作用下进行庚烷异构化反应,正庚烷转化率最高为26.8%,异庚烷选择性高于99.5%。
Ethanol-hydrochloric acid extraction-assisted high-temperature roasting(A two-step approach of extraction and roasting)was adopted to remove template(PEO-PPO-PEO,P123).After being modified by Al in situ doping,a wormlike Al-KIT-6 mesoporous molecular sieve was synthesized by hydrothermal crystallization method.Also,Ni/Al-KIT-6 metal-acid bi-function catalyst with different nickel loads was prepared by impregnation method.The physical and chemical properties of Al-KIT-6 molecular sieve and catalyst samples were analyzed by characterized means,such as XRD,N_(2) adsorption-desorption,NH_(3)-TPD,IR,SEM and TEM.Later,n-heptane isomerization reaction performance of Ni/Al-KIT-6 catalyst samples was evaluated using n-heptane as the reactive material.The results reveal that the template can be removed effectively by the two-step approach of extraction and roasting.Compared with the molecular sieve samples prepared by removing the template using conventional roasting or extraction methods,KIT-6 molecular sieve samples prepared by removing the template using the two-step approach are characterized by greater specific surface area,larger pore volume and more uniform pore size distribution;Al atoms introduced into the molecular sieve framework has increased the acidity of the molecular sieve;when the hydrogen flow rate is 30 mL/min,the weight hourly space velocity(WHSV)is 7.6 h^(-1) and the reaction temperature is 190℃;at normal pressure,n-heptane isomerization reaction occurs under the action of Ni/Al-KIT-6 catalyst whose nickel load mass fraction is 5%,during which the n-heptane conversion rate is 26.8%,and the selectivity to isoheptanes can reach 99.5%.
作者
周一思
马守涛
张威
张微
所艳华
汪颖军
ZHOU Yisi;MA Shoutao;ZHANG Wei;ZHANG Wei;SUO Yanhua;WANG Yingjun(College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing 163318, China;Daqing Petrochemical Research Center, Petrochemical Research Institute, PetroChina, Daqing 163714, China;No.3 Oil Production Plant, Daqing Oilfield Co. Ltd, PetroChina, Daqing 163000, China)
出处
《石油学报（石油加工）》
EI
CAS
CSCD
北大核心
2021年第6期1346-1356,共11页
Acta Petrolei Sinica(Petroleum Processing Section)
基金
东北石油大学国家基金培育项目(2017PYYL-03)资助。
