蒙皂族粘土基催化材料的设计制备和催化作用

Designed Preparation and Catalysis of Smectite Clay-Based Catalytic Materials

较全面地评述了蒙皂族粘土矿物层间催化活性组分的设计制备及其催化应用的研究新进展.2:1型层状结构的蒙皂族粘土具有层间阳离子的可交换性和活性物种的可嵌层性,使层间设计和构造催化活性中心极具灵活性.迄今在蒙皂族粘土层间可设计制备的物种有金属阳离子、金属单质、金属氧化物及复合氧化物、金属络合物、金属硫化物和碳等.作为一类主客体纳米复合催化材料,对层间物种的分布和微结构的深入认识,进而能精确调控,是开发和应用此类材料的关键和难点.蒙皂族粘土基催化材料已在氧化、脱水、加氢、裂化、异构化和烷基化等催化反应中显示出工业应用前景.最后,评述了该领域尚存在的若干科学问题和发展方向.

This paper presents a critical overview of research progress in the synthesis, properties, structure, and applications of smectite clay-based catalytic materials. The 2：1-type layered structure of smectites, which consists of two Si-O tetrahedral sheets sandwiched by a metal-oxygen octahedral sheet, along with changeable composition of layers, exchangeable cations within interlayers, and intercalation of active species, allows numerous preparation strategies to produce a variety of clay-based catalytic materials. So far the catalytically active species intercalated into the interlayers of clays are metal ions, zero-valent metal, metal oxides, metal complexes, metal sulfides, and carbon, and so forth. The scientific knowledge and accurate control of the distribution and the microstructure of the guest species in the interlayer are critical issues. Such advanced clay-based materials obtained by preparation through designed species within interlayers have provided promising applicability in a number of catalytic reactions such as oxidation, dehydration, hydrogenation, cracking, isomerization, and alkylation. Several key problems and prospects are also remarked.