自组装低负载量Pd/γ-Al2O3催化剂催化氧化甲苯  

A Self-assembled Pd/γ-Al2O3 Catalyst with Low Loading for Catalytic Oxidation of Toluene

作　　者：李奔 周贝 李思汉 严新焕[1] LI Ben;ZHOU Bei;LI Si-han;YAN Xin-huan(State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology,Zhejiang University of Technology,Hangzhou 310014,Zhejiang,China)

机构地区：[1]浙江工业大学绿色化学合成技术国家重点实验室培育基地

出　　处：《精细化工》2018年第9期1555-1561,共7页Fine Chemicals

基　　金：浙江省科技计划项目(2016C31104);国家重点研发计划(2017YFC0210900)~~

摘　　要：以PdCl2和Pd2（dba）3[三（二亚苄基丙酮）二钯]为前驱体，通过浸渍法、沉积沉淀法和自组装法分别制备了负载量（质量分数，下同）为0．03％的Pd／γ-Al203-IM、Pd／γ-Al203-DP和Pd／γ-Al203-SA催化剂用于催化氧化甲苯。在甲苯体积分数为0．1％、空速（sv）为18000mL／（g.h）条件下，Pd／γ-Al203-SA催化剂上甲苯实现98％转化率的温度（T98）为220℃，比Pd／γ-Al203-DP和Pd／γ-Al203-IM分别降低了40和75℃。通过N2吸附-脱附、XRD、TEM、XPS和H2．TPR对催化剂进行了表征。结果表明：自组装法制备的Pd／γ-Al203-SA催化剂的比表面积（345m2／g）和孔体积（0．52cm3／g）最大，Pd纳米粒子（PdNPs）平均粒径最小（5．0nm），活性物种主要以PdO的形式高度分散于载体y-Al203表面。此外，PdO与载体γ-Al203之间的强相互作用（SMSI）促进了其催化氧化甲苯的活性。Pd/γ-Al203-IM, Pd/γ-Al203-DP and Pd/γ-Al203-SA catalysts with 0.03% （mass fraction） Pd loading for catalytic oxidation of toluene were respectively prepared by the impregnation, deposition-precipition, and self-assembly methods using PdC12 and Pd2（dba）3 as precursors. The temperature for conversion of 98% toluene （T98） over Pd/γ-Al203-SA catalyst was 220 ℃ under the conditions of toluene volume fraction at 0.1% and space velocity （SV） at 18000 mL/（g.h）, which was 40 and 75 ℃lower than those of Pd/y-Al203- DP and Pd/γ-Al203-IM. The catalysts were characterized by N2 adsorption-desorption, XRD, TEM, XPS, H2-TPR. The results indicated that Pd/γ-Al203-SA catalyst possessed the largest specific surface area （345 m2/g） and pore volume （0.52 cm3/g）, the smallest average diameter （5.0 nm） of Pd nanopaticles （NPs）, and the main active PdO species were well-dispersed on the surface of the y-Al203 support. Besides, the strong metal-support interaction （SMSI） between PdO and γ-Al2O3 promoted its oerformance in catalytic oxidation of toluene.

关 键 词：自组装 Pd/γ-Al203 催化氧化 甲苯 挥发性有机物 催化技术 

分 类 号：O643[理学—物理化学] X13[理学—化学]