镍基氨分解制氢催化剂的制备及性能

Preparation and properties of Ni-based catalyst for hydrogen production by ammonia decomposition

用浸渍法制备Ni/Al_2O_3和Ni/xMo-Al_2O_3催化剂,以氨分解为模型反应,考察Ni负载量、焙烧温度、溶剂和助剂等合成条件对催化剂催化性能的影响,通过XRD和TG-DTG表征方法对催化剂进行表征。结果表明,最佳合成条件:Ni负载质量分数为16%,焙烧温度350℃,采用丙酮为溶剂制备的Ni/Al_2O_3催化剂具有较好的催化活性。500℃添加质量分数3%的助剂Mo可以使Ni/Al_2O_3催化剂的活性显著提高39%,Ni/3%Mo-Al_2O_3催化剂的氨分解率达93.5%。

Ni/Al2O3 and Ni/xMo-Al2O3 catalysts were prepared by impregnation method and the influence of Ni loadings, calcination temperature, the solvents and the additives on catalytic properties of the catalysts was investingated using ammonia decomposition as the model reaction. The catalysts were characterized by XRD and TG-DTG. The results indicated that Ni/Al2O3 catalyst exhibited better catalytic activity under the optimum preparation condition of Ni loading 16% （mass fraction）, calcination temperature 350 ℃, and acetone as the solvent. At 500 ℃ the activity of Ni/Al2O3 for ammonia decomposition was significantly increased by 39% by adding 3% Mo to the catalyst and the ammonia conversion of 93.5% was attained over Ni/3% Mo-Al2O3 catalyst.