论文部分内容阅读
用IR、Raman光谱研究了SO2 -4 /TiO2 固体酸在不同烧结温度下的结构、晶相转变和表面酸中心。结果表明 ,SO2 -4 与TiO2 表面的结合为螯合式双配结构。当烧结温度小于 5 0 0℃时 ,SO2 -4 /TiO2 样品具有较高的结构稳定性 ,晶相结构以锐钛矿为主 ,表面B酸位数目约是L酸位数目的 2倍。当烧结温度大于5 0 0℃时 ,随着烧结温度的升高 ,表面结合的SO2 4 逐渐流失 ,晶相从锐钛矿转变为金红石 ,表面B酸位减少并消失。
The structures, phase transitions and surface acid sites of SO2-4 / TiO2 solid acid at different sintering temperatures were investigated by IR and Raman spectroscopy. The results show that the binding of SO2 -4 to the surface of TiO2 is chelated double-structure. When the sintering temperature is less than 500 ℃, SO2-4 / TiO2 samples have high structural stability. The anatase phase is mainly composed of anatase, and the number of B acid sites on the surface is about twice that of L acid sites. When the sintering temperature is higher than 500 ℃, as the sintering temperature increases, the surface bound SO2 4 gradually lost, the crystalline phase transformed from anatase to rutile, and the surface B acid sites decreased and disappeared.