摘要
采用水热合成法制备了介孔分子筛 MCM-41,并利用浸渍方法将磷钨酸负载在 MCM-41分子筛上,经煅烧得到 PW/MCM-41催化剂;利用 X 射线衍射、傅里叶变换红外光谱、N_2吸附-脱附和 NH_3程序升温脱附等手段对催化剂进行了表征;考察了 PW/MCM-41催化剂对苯甲醚及1,4-二甲氧基苯的乙酰化反应的催化性能。表征结果显示,磷钨酸负载到 MCM-41分子筛上后,保持了 Keggin 结构,MCM-41分子筛保持了介孔结构。实验结果表明,PW/MCM-41催化剂的活性随磷钨酸负载量的增大而降低;磷钨酸质量分数为30%的 PW/MCM-41催化剂上反应底物的转化率最高,使用该催化剂0.8 g,以10 mL 二氯甲烷为溶剂,在苯甲醚用量0.01 mol、乙酸酐用量0.02 mol、反应温度140℃、反应时间4 h 的条件下,苯甲醚转化率可达77.0%,对甲氧基苯乙酮的选择性为96.5%。
PW/MCM-41 catalyst was prepared by supporting phosphotungstic acid （PW） on mesoporous MCM-41 molecular sieves via impregnation and then calcination. The said molecular sieves were synthesized by hydrothermal method. The catalysts were characterized by means of XRD, FTIR, nitrogen adsorption and NH3-TPD. The original Keggin structure of PW and mesoporous structure of MCM-41 molecular sieves were maintained after supporting PW on MCM-41 molecular sieves. PW/MCM-41 catalyst was used in acetylation of 1,4-dimethoxybenzene or anisole. The catalyst activity decreased with increase of PW loading. PW/MCM-41 catalyst with 30% （ mass fraction） PW is preferable. Using this catalyst in acetylation of anisole, conversion of 77.0% and selectivity of 96.5% to p-methoxy acetophenone were obtained under the conditions： 140 ℃, 4 h, 10 mL dichloromethane as solvent, 0.8 g catalyst, 0.02 mol of acetic anhydride and 0.01 mol of anisole.
出处
《石油化工》
EI
CAS
CSCD
北大核心
2008年第9期931-936,共6页
Petrochemical Technology
作者简介
冯磊（1982-），男，河北省石家庄市人，硕士生，电话022—26564279，电邮topflei@126．com。
联系人：赵继全，电话022-60202926，电邮zhaojq@hebut．edu．cn。
