HPW/Al2O3催化剂的制备、表征及催化四氢呋喃聚合的研究

Preparation, Characterization and Catalytic Performance of HPW/Al2O3 for THF polymerization

摘要:

采用溶胶-凝胶法结合超临界流体干燥技术制备了Al2O3气凝胶载体，以浸渍法制得Al2O3气凝胶负载磷钨酸固体酸催化剂（HPW/Al2O3）。利用N2吸附-脱附、X射线粉末衍射、NH3程序升温脱附、傅里叶红外、吡啶吸附红外等手段对HPW/Al2O3催化剂的织构、结构、表面性质等进行了表征，并考察了其在四氢呋喃聚合反应中的催化性能。结果表明：HPW/Al2O3催化剂负载量在50%～70%范围内能较好的保留HPW的Keggin结构，具有强的Bronsted酸性特征，催化剂的酸量与酸强度随HPW负载量的提高呈递增趋势，而聚四氢呋喃(PTMEG)的收率及分子量与催化剂的酸量间存在线性关系，酸量越大，收率越高，分子量越低。

Abstract:

A series of HPW/Al2O3 solid acid catalyst with loading from 10% to 70% was synthesized. These catalysts were characterized by N2 adsorption-desorption, XRD, NH3-TPD, FT-IR spectroscopy and Py-IR spectroscopy. The above studies indicated that HPW kept its Keggin type structure in the loading range of 50%～70% .The catalysts had strong Brönsted acid and their total acidity increased with the laoding of HPW. The catalytic activity of these catalysts were evaluated by carrying out polymerization of tetrahydrofuran (THF).The results indicated that higher acidic catalyst led to the higher yield of PTMEG, yet the lower average molecular of PTMEG.