低浓度甲烷流向变换催化燃烧

Catalytic Combustion of Lean Methane in a Reverse-flow Reactor

以水铝石和改性过的γ-Al2O3为原料制备了铝溶胶涂层,考察了不同涂层固含量对催化剂比表面积的影响.以贵金属Pd作为催化剂活性成分,研究了催化剂在不同Pd含量和还原条件下催化活性的变化规律,并考查了催化剂预热温度、系统换向周期对反应系统床层温度的影响.结果表明:涂层固含量20%、Pd负载量占涂覆层质量分数1.5%为催化剂最佳制备条件;当催化剂预热温度为450℃、空速为15 000 h-1、换向周期为10 min、甲烷体积分数为0.2%时,甲烷转化率最高可达85%.

The washcoat deposited on a ceramic honeycomb was prepared with modified γ-Al2 O3 and pseudo boehmite. The effect of gel solid content on the gel viscosity and coating ability was investigated. The monolithic catalysts were made with noble metal being active component, cordierite and modified γ-Al2 O3 being the first and second carriers. The effects of Pd content and deoxidation on the monolith catalyst performance, the effects of the cyclic period, and preheated temperature on the operation performance of reactor were investigated. Result show that the quantity supported Pd of coating layer being 1. 5% and the coating of solid content being 20% was the best. The methane conversion attained 85% when the catalyst preheat temperature was 450 ℃, space velocity was 15 000 h - 1 , and reversing cycle was 10 min.