摘要
采用超临界流体干燥法制备VPO催化剂 ,并在N2 气氛或反应气氛 (1.5 %n -C4 H10 /17.0 %O2 /N2 ,体积比 )下进行活化 ,应用BET、XRD、XPS等表征手段 ,考察了各VPO催化剂粒子的比表面积、晶相结构、表面性质。实验表明 ,活化气氛不同 ,对催化剂物理性质影响也不同。在N2 气氛中活化的样品比表面积大于反应气氛中活化的样品 ;活化气氛对催化剂的晶相组成影响不大 ;在N2 气氛中活化的样品V的 2p电子结合能较反应气氛中活化有所降低 。
VPO catalysts were prepared by the supercritical fluid drying (SCFD) and were activated in the reactant mixture or in nitrogen after SCFD. BET, XRD and XPS techniques were used to investigate the surface area, the phase composition and the oxidation state of various samples. The results indicated that the activation atmosphere had effects on the physical properties of VPO catalysts. VPO catalysts had the larger surface area activated in the nitrogen at 673K for 6h. The samples phase composition was not changed by activation in the reactant mixture or in nitrogen. The oxidation state of surface vanadium atoms of samples was around +4, similar to that of vanadium in (VO) 2P 2O 7. Activation in the nitrogen atmosphere the samples surface P/V ratio was a little higher, but V 2p electron binding energy was a little lower.
出处
《石油与天然气化工》
CAS
CSCD
北大核心
2002年第3期111-113,共3页
Chemical engineering of oil & gas
