Cr_(2)S_(3)催化H_(2)S分解制氢的活性与动力学研究

Study on activity and kinetics of H2S decomposition catalyzed by Cr_(2)S_(3)for hydrogen production

目的将H_(2)S分解制氢既能解决废气污染问题,又能实现其资源化的高值利用。制备中低温段高效稳定的H_(2)S分解催化剂,掌握其催化动力学行为,有助于构建硫化学链促进的H_(2)S高效分解的新工艺。方法采用溶液燃烧法制备了Cr_(2)S_(3)催化剂,通过XRD、BET和SEM/EDS等方法表征了催化剂组成和结构,同时通过实验考查其在H_(2)S催化分解制氢中的催化性能、稳定性以及反应动力学,并研究了制备时燃料比例对催化剂性能的影响。结果在φ(H_(2)S)=5%,气体空速(GHSV)=24000 h−1的反应条件下,Cr_(2)S_(3)-T1.50具有最高的H2S转化率,在800℃时可达16.01%,并且无其他副反应;反应动力学分析表明,Cr_(2)S_(3)-T1.50催化H_(2)S分解的表观活化能为50.7 kJ/mol。结论溶液燃烧法制备出的Cr_(2)S_(3)催化剂在400~800℃具有极好的活性和稳定性,能够极大地降低H_(2)S分解的表观活化能。

Objective The decomposition of hydrogen sulfide to produce hydrogen can avoid waste gas pollution and utilize the resource to a greater degree.The preparation of high-efficiency and stable H_(2)S decomposition catalysts at medium and low temperature and the exploration of their catalytic kinetic behavior are helpful to construct a new process for the efficient decomposition of H_(2)S promoted by the sulfur chemical chain.Methods The catalyst Cr_(2)S_(3)was prepared using the solution combustion method.The composition and structure of the catalyst were characterized by XRD,BET and SEM/EDS.Additionally,its catalytic performance,stability and reaction kinetics in the catalytic decomposition of H_(2)S for hydrogen production were investigated.This paper also studies the effect of fuel ratio on the catalyst's hydrogen production performance.Results Under the reaction conditions ofφ(H_(2)S)=5%and GHSV=24000 h−1,Cr_(2)S_(3)-T1.50 has the highest H_(2)S conversion rate,up to 16.01%at 800℃,and no other side reactions appear.The kinetic analysis of the reaction shows that the apparent activation energy of H_(2)S decomposition catalyzed by Cr_(2)S_(3)-T1.50 is 50.7 kJ/mol.Conclusion The Cr_(2)S_(3)catalyst prepared with the solution combustion method has excellent hydrogen production activity and stability at 400-800℃and can significantly reduce the apparent activation energy of hydrogen sulfide decomposition.