高选择性乙醇脱水制乙烯催化剂的研制

Development of High Selectivity Catalysts for Preparing Ethylene from Ethanol Dehydration

采用在氧化铝中引入氧化硅组份和水蒸汽处理手段来提高乙醇脱水制乙烯催化剂的酸量,从而达到提高乙烯选择性的目的。考察了氧化硅含量和水蒸汽处理条件对催化剂活性和稳定性的影响。结果表明,氧化硅含量是催化剂选择性和稳定性兼顾的关键,适当水蒸汽处理有利于提高催化剂的选择性。以20%氧化硅含量制得的氧化硅-氧化铝复合催化剂,再在550℃的水蒸汽处理4h,可得到高转化率(99.98%)和高选择性(98.70%)的乙醇脱水催化剂,与工业催化剂相比乙烯选择性提高2个多百分点。

The SiO2-Al2O3 catalyst with more content of acid used in ethanol dehydration to ethylene can be obtained by incorporating SiO2 into A1203 and processing steaming catalyst, which increased ethylene selectivity. Effect of SiO2 content and the steaming conditions on the catalytic activity and stability was investigated. The results showed that SiO2 content was a key factor for both high ethylene selectivity and good catalytic stability. The SIO2-A1203 catalyst with high ethanol conversion （99.98%） and high ethylene selectivity （98.70%） was obtained when the catalyst with 20% SiO2 content was treated at 550℃ steaming for 5 h. The ethylene selectivity was 2% more comparing with industry catalyst.