利用 X 射线衍射(XRD)，X 射线光电子能谱(XPS)及活性测试对铈钛复合氧化物的结构及催化脱硫特性进行了研究。结果表明：当铈?钛摩尔比(n(Ce)/n(Ti))≥5：5时，铈钛复合氧化物形成固溶体；当 n(Ce)/n(Ti)=7：3(即Ce0.7Ti0.3O2)时，具有最佳的催化脱硫效果；500°C 下 SO2的转化率达到93%，单质硫的产率达到99%。根据Ce0.7Ti0.3O2的活性测试曲线发现：未经预处理的 Ce0.7Ti0.3O2约10 min 后开始逐渐被反应气体活化，并在60 min后达到稳定活化状态。通过对不同反应时间下所得 Ce0.7Ti0.3O2进行 XPS 分析发现： CeO2为活性物质，在反应过程中形成 Ce4+/Ce3+氧化还原电对和活性氧空位，而 TiO2仅起到稳定催化剂结构的作用。Ce0.7Ti0.3O2催化 SO2+CO反应48 h 后未出现硫化现象，始终保持结构的稳定，表现出较好的抗硫中毒性能。
The structure and catalytic desulfurization characteristics of CeO2?TiO2 mixed oxides were investigated by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and catalytic activity tests. According to the results, a CeO2?TiO2 solid solution is formed when the mole ratio of cerium to titanium n(Ce):n(Ti) is 5:5 or greater, and the most suitable n(Ce):n(Ti) is determined as 7:3, over which the conversion rate of SO2 and the yield of sulfur at 500 °C reach 93% and 99%, respectively. According to the activity testing curve, Ce0.7Ti0.3O2 (n(Ce):n(Ti)=7:3) without any pretreatment can be gradually activated by reagent gas after about 10 min, and reaches a steady activation status 60 min later. The XPS results of Ce0.7Ti0.3O2 after different time of SO2+CO reaction show that CeO2 is the active component that offers the redox couple Ce4+/Ce3+ and the labile oxygen vacancies, and TiO2 only functions as a catalyst structure stabilizer during the catalytic reaction process. After 48 h of catalytic reaction at 500 °C, Ce0.7Ti0.3O2 still maintains a stable structure without being vulcanized, demonstrating its good anti-sulfur poisoning performance.
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