对SBA 15负载的钒、钼、钨氧化物催化的甲烷选择氧化反应性能进行了比较 ,发现VOx/SBA 15催化剂优于MoOx/SBA 15和WOx/SBA 15催化剂 .针对钒氧化物催化剂 ,考察了不同钒源、不同载体以及少量P元素的添加对催化性能的影响 ,结果表明以SBA 15为载体的催化剂的性能好于MCM 41和Cab O Sil为载体的催化剂 ;与V2 O5,VO(C2 O4)相比 ,NH4VO3是制备性能良好的VOx/SBA 15的钒源 ;在VOx/SBA 15中 ,添加少量P元素后 ,HCHO的选择性有一定程度的提高 .XRD ,N2 物理吸附、UV Raman和H2 TPR表征结果表明 ,负载量低于 3wt%时 ,钒组分可能主要以高分散的单核的VOx 物种存在 ,我们推测该物种对甲烷选择氧化制甲醛起关键作用 .The VO x/SBA-15 has been found to be a better catalyst for the selective oxidation of methane to formaldehyde than SBA-15-supported Mo and W oxides. The influences of catalyst support and vanadium source on catalytic performances have been studied. The results show that SBA-15 is a better support than MCM-41 and Cab-O-Sil, and the catalyst with NH 4VO 3 as the precursor exhibits higher performances. The addition of phosphorus has been found to enhance slightly the selectivity to HCHO. Characterizations by XRD, N 2 physical adsorption, Raman spectroscopy and H 2-TPR suggest that the supported VO x species with loading amounts lower than 3 wt% be highly dispersed (probably as monomer) and contribute to the selective oxidation of methane to formaldehyde.国家自然科学基金 (Nos.2 0 0 2 1 0 0 2 ,2 0 2 730 54);; 国家重点基础研究发展规划项目 (No .G1 9990 2 2 4 0 8);; 教育部留学回国启动基金资助项
