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采用双股并流共沉淀法制备了SnCuO系列催化剂 ,测定了它们对甲烷燃烧反应的催化活性及抗硫中毒性能 ,并采用XRD ,BET ,XPS ,DTA TG和FT IR等技术对催化剂进行了表征 .比表面积和活性测试结果表明 ,SnCuO系列样品的比表面积均大于纯氧化物 ,其低温催化活性大大高于纯氧化物 .在Sn Cu原子数比接近 1时 ,其比表面积最大 (超过 10 0m2 g) .具有最大比表面积的样品SnCu4和SnCu5的活性最高 .进一步测定了SnCu4样品的抗硫中毒性能 .结果发现 ,在 5 0 0℃下 ,反应刚开始时甲烷的转化率为 98% ,随着SO2 的不断通入 ,催化剂的活性逐渐降低 ,到 12h后基本稳定 ,此时甲烷转化率仅为5 0 % .采用FT IR和热重分析方法对SnCu4硫中毒的机理进行了研究 ,发现其中毒原因在于SnCuO系列催化剂中的CuO与SO2 反应几乎完全转化为CuSO4,导致催化剂活性降低
SnCuO catalysts were prepared by co-precipitation and co-precipitation method. Their catalytic activity on methane combustion reaction and anti-sulfur poisoning performance were measured. The catalysts were characterized by XRD, BET, XPS, DTA TG and FT IR The specific surface area and the activity test results show that the specific surface area of SnCuO series is larger than that of pure oxide, and its catalytic activity at low temperature is much higher than that of pure oxide.When the atomic ratio of Sn Cu is close to 1, its specific surface area is the largest (over 10 0m2 g) .The SnCu4 and SnCu5 samples with the highest specific surface area showed the highest activity.The anti-sulfur poisoning performance of SnCu4 sample was further determined.The results showed that the conversion of methane was 98% at the beginning of the reaction at 550 ℃ With the continuous access of SO2, the activity of the catalyst gradually decreased, and basically stabilized after 12h, when the methane conversion rate was only 50% .The mechanism of sulfur poisoning of SnCu4 was studied by FT IR and TG method, The reason for the poisoning is that the reaction of CuO with SO2 in the SnCuO series catalyst is almost completely converted to CuSO4, resulting in a decrease in catalyst activity