摘要
以十二胺(DDA)为模板剂,利用杂原子掺杂技术合成了Cs-HMS载体。以n-丁醇为溶剂,按照Cs/磷钨酸(HPW)摩尔比为1.5,等体积浸渍法制备了负载HPW的催化剂HPW/Cs-HMS,并对载体及催化剂进行了表征分析,考察了负载量对催化剂结构及其醋酸甲酯(MeOAc)水解性能的影响。结果发现,随着HPW负载量的增加,Cs-HMS介孔结构的规整度、比表面积及孔容显著下降,其结构及形貌由短程有序的球状介孔逐渐转化为无序的片状微孔,最佳的HPW负载量为40%。40%HPW/Cs-HMS在55℃、9 g H2O、m(H2O)/m(MeOAc)=1、HPW总用量为1 g的条件下,反应2 h后,MeOAc转化率为45.7%,并具有优良的耐温性。在100℃、4.5 g H2O、18 gMeOAc、HPW总用量为0.5 g的条件下,反应0.5 h,MeOAc转化率为21.8%,比相同条件下酸性树脂NKC-9的活性高5%,重复使用5次,活性维持在20.8%,而NKC-9则逐次失活。
A series of HPW/Cs-HMS catalysts with different HPW loadings （the molar ratio of Cs to HPW is 1.5） were prepared by the equal volume incipient impregnation method, in which n-butanol was used as solvent, and the carrier, cesium-containing molecular sieve（Cs HMS）, was synthesized by the technique of doped atoms with dodecylamine （DDA） as template. The HPW/ Cs-HMS catalysts were characterized by various means. The influences of HPW loadings on the structural properties and catalytic performance of HPW/Cs HMS for methyl acetate hydrolysis were investigated. The results showed that with the increase of HPW loadings the mesoporous structural order, the BET surface area and the pore volume of molecular sieve drastically decreased, thestructure and shape of HPW/Cs-HMS catalyst turned from a short-range-ordering mesopore and a hollow micrometric spherical shape to the disordered micropore and the flaky shape gradually. The optimal HPW loading of HPW/Cs-HMS catalyst for methyl acetate hydrolysis was 40%. The hydrolysis conversion of methyl acetate on 40%HPW/Cs-HMS reached 45.7% in 2 h at 55℃ with the conditions that H2O was 9 g, m（H2O）/m（MeOAc）=1, and the total HPW loading was 1 g, while under the conditions that MeOAc was 18 g, H2O was 4.5 g and the total HPW loading was 0.5 g, the hydrolysis conversion of methyl acetate reached 21.8% in 0.5 h at 100℃, which had anenhancement of 5% compared to NKC-9 resin. The activity of 40% HPW/Cs-HMS was not changed after 5 cycle uses, keeping 20.8%, but the conversion of methyl acetate on NKC-9 decreased gradually with the increase of cycle uses.
出处
《石油学报（石油加工）》
EI
CAS
CSCD
北大核心
2009年第4期509-515,共7页
Acta Petrolei Sinica(Petroleum Processing Section)
基金
国家自然科学基金项目(20671020)
中国石油化工股份有限公司科技开发项目(X504003)
福建省高等学校新世纪优秀人才支持计划项目(HX2006-100)资助
关键词
Cs—HMS
磷钨酸
浸渍
醋酸甲酯
水解
Cs-HMS
phosphotungstic acid
impregnation
methyl acetate
hydrolysis
