负载型MoO_3/SiO_2催化剂催化酯交换合成草酸二苯酯的反应性能  

CATALYTIC ACTIVITY OF SUPPORTED MoO_3/SiO_2 CATALYSTS IN ESTER EXCHANGE FOR SYNTHESIS OF DIPHENYL OXALATE

作　　者：边丽[1] 王胜平[1] 潘发勇[1] 张永光[1] 马新宾[1] 

机构地区：[1]天津大学绿色合成与转化教育部重点实验室,天津300072

出　　处：《石油学报（石油加工）》2007年第2期88-92,共5页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：国家自然科学基金项目(20276050);天津市科委科技攻关培育项目(033103511)资助

摘　　要：以钼酸铵、SiO2为原料,采用浸渍法制备了负载型MoO3/SiO2催化剂。通过草酸二乙酯(DEO)与苯酚的酯交换反应合成了草酸二苯酯(DPO)。采用XRD探讨了催化剂表面活性组分的分散状态对草酸二乙酯和苯酚酯交换反应的影响。结果表明,呈高度分散的无定型MoO3有利于该反应的进行,而大量晶态MoO3的出现导致了催化活性的降低。考察了催化剂负载量、反应温度、反应时间和原料摩尔配比等对反应性能的影响。当负载量为6%(质量分数)时,MoO3/SiO2的催化性能最佳,草酸二乙酯的转化率为54.9%,草酸二苯酯的收率为13.7%,乙基苯基草酸酯(EPO)的收率为41.2%;目的产物草酸二苯酯和乙基苯基草酸酯的总选择性为100%。A series of supported MoO3/SiO2 catalysts with different MoO3 loadings were prepared by the impregnation method, and their activities in the transesterifieation of diethyl oxalate （DEO） with phenol to produce diphenyl oxalate （DPO） were tested. The cata!ysts were characterized by X-ray diffraction （XRD）, and the relationship between the catalytic acticity of MoO3/SiO2 and the structure of MoO3 dispersed on the surface of SiO2 was studied in detail. The results indicated that amorphous MoO3 with high dispersion was favorable for the production of DPO. However, the formation of a great amount of the crystal MoO3 resulted in the decrease of catalytic activity. The effects of reaction temperature, reaction time, molar ratio of reagent, MoO3 loadings and so on were investigated. The catalyst of MoO3/SiO2 with 6% （mass fraction） MoO3 performed best, giving 54. 9% conversion of DEO, 13. 7% yield of DPO, 41. 2% yield of ethyl phenyl oxalate （EPO） and 100% selectivity to target products of DPO and EPO.

关 键 词：草酸二乙酯(DEO) 草酸二苯酯(DPO) 乙基苯基草酸酯(EPO) 负载型M003/SiO2催化剂 酯交换 

分 类 号：TQ245[化学工程—有机化工]