几种碱金属元素对硫酸催化剂低温活性的影响
来源期刊：中南大学学报(自然科学版)2000年第5期
论文作者：陈振兴 黄彩娟 方忠和 叶华 刘今
文章页码：425 - 428
关键词：助催化剂;碱金属元素;熔盐;低温活性;硫酸;二氧化硫
Key words：catalyst promoter; alkali-metal element; melting salt; activity under low temperature; sulfuric acid; sulfur dioxide
摘 要：研究了用冶金废液制备的低温硫酸催化剂中铯、铷、锂等碱金属元素的助催化作用和熔盐用量对催化剂低温活性的影响.结果表明,铯的低温助催化效果最好,其用量宜控制在n(Cs)/n(V)=0.3~0.6.当n(Cs)/n(V)=0.6时,410℃的SO2转化率达42.5%,比无铯催化剂的SO2转化率高18.5%.铷的加入会降低催化剂的低温活性,宜采取措施降低废液中的铷含量.在多种碱金属元素混合使用的情况下,锂元素有较好的助催化作用,其最佳用量为n(Li)/n(V)=0.4,410℃时SO2转化率达46%.活性组分含量对催化剂低温活性和高温活性影响较大, n(M)/n(V)宜小于4.5.
Abstract: The thesis presents the effect of alkali-metal elements (Cs, Rb, Li ) and dosage of melting salt on activity of sulfuric acid catalyst at low temperature, which has been prepared with metallurgical waste liquid. The result shows that cesium is the best promoter among all the alkali-metal elements and the suitablen(Cs)/n (V) is about 0.3~0.6. Whenn(Cs)/n(V)=0.6, the conversion of SO2 increases to 42.5% at 410℃, which is 18.5% higher than the activity of catalyst without cesium. The effect of rubidium on activity of sulfuric acid catalyst at low temperature is negative, so rubidium in metallurgical waste liquid should be decreased as little as possible. Lithium has a good effect on activity of catalyst at low temperature if there exist manifold alkali metals in catalyst, its optimum dosage isn(Li)/n(V)=0.4 and then the conversion of SO2 is 46% at 410℃. Furthermore, if content of active components is excessive, the activity of catalyst at low temperature will be reduced on the contrary and the suitablen(M)/n(V) is less than 4.5.
