中文摘要：

用快速燃烧法制备了纳米钒钛硫催化剂并采用固定床反应器考察了甲醇氧化一步制取二甲氧基甲烷（DMM）的性能。结果表明硫的改性有效抑制了甲酸甲酯（MF）的生成，显著提高了DMM选择性，这与硫对催化剂表面酸性修饰有关。XRD，FT-IR，NH3-TPD和H2-TPP-MS结果表明，硫以硫酸根形式存在，硫物种的存在没有改变钒氧化物的赋存形式及其氧化还原性能，但显著增加了催化剂表面酸性中心。反应前后催化剂硫酸根含量及催化剂表面酸性均无明显变化，催化剂具有良好的稳定性。

英文摘要：

The sulfur modified nanostructured vanatia-titania catalysts were prepared by the rapid combustion method and applied to the one-step oxidation of methanol to dimethoxymethane （DMM）. The results showed that the addition of sulfur efficiently inhibited the formation of by-product methyl formate and greatly increased DMM selectivity and yield due to the acidity modification of catalyst surface. FT-IR, NH3-TPD and H2-TPR-MS results showed that the sulfur mainly existed as sulfate and the addition of sulfur did not change the existing state of VOx and its reducibility, while it greatly enhanced the intensity and number of weaker acidic sites. There was no change of sulfate content and catalyst surface acidity before and after reaction, which led to good stability of the sulfur modified catalyst in the methanol oxidation.