制备方法对锰Mn掺杂钾六铝酸盐催化剂催化甲烷燃烧性能的影响

摘要

Manganese substituted potassium hexaaluminate catalyst was prepared by co-precipitation method,solgel method and reverse microemulsion-mediated method.The title catalyst was calcined at 1 200 ℃ and characterized by XRD and TG-DTA techniques.The catalytic activity was evaluated for methane combustion.The specific surface area of them was calculated using the BET model.The samples exhibit significant catalytic activity for methane combustion at 800 ℃.Upon calcination at 1 200 ℃ the K2MnAl11O19 prepared by reverse microemulsion-mediated method retains a specific surface area of 34 m2 · g-1 and shows an excellent activity for methane combustion (the conversions of 10％ and 90％ are obtained at 458 and 670 ℃,respectively).%以甲烷催化燃烧为目标反应,通过共沉淀法、溶胶凝胶法和反相微乳液法制备了Mn掺杂六铝酸盐催化剂,用XRD和TG-DTA技术对催化剂进行了物理性能表征,通过BET模型计算了其比表面积.结果说明3种方法所制备催化剂经1 200℃焙烧4h后均可以形成完整的六铝酸盐晶型,同时都具有高的催化性能和高温稳定性,其中反相微乳液法制备的K2MnAl11O19催化剂具有较高的比表面积和甲烷催化燃烧活性,起燃温度T10％为458℃,至676℃甲烷完全转化.