镍钨基硫化态和氮化态催化剂对十氢萘选择性开环性能研究

Study on performance of Ni-W based sulfide and nitride catalysts for selective ring opening of decalin

通过不同预处理方式制备镍钨硫化态和氮化态催化剂,利用X射线衍射、吡啶红外光谱、元素分析、CO滴定等技术对催化剂进行表征。以十氢萘为探针分子,利用固定床反应器考察不同预处理方式及负载量对催化剂十氢萘选择性开环反应转化率和寿命的影响规律。结果表明,氮化态催化剂初始转化率及选择性开环活性高,这与氮化态催化剂金属位活性高有关,但其稳定性低于硫化态催化剂,这是由于十氢萘在金属位脱氢后未能及时转移至酸性位开环,使其发生过度脱氢导致结焦失活。

A series of nickel-tungsten sulfide and nickel-tungsten nitride catalysts are prepared by different pretreatment methods,and characterized by means of techniques such as XRD,Py-IR,HRTEM,elemental analysis,and CO titration.Using decalin as a probe molecule,the influences of different pretreatment methods and different loading amount on the performance of the catalyst for selective ring opening reaction of decalin are investigated in a fixed bed reactor.It is found that Ni-W nitride catalyst delivers higher initial conversion rate and selective ring opening activity than Ni-W sulfide catalyst,because the former has higher metal site activity.Ni-W nitride catalyst exhibits a lower stability than Ni-W sulfide catalyst,which is due to the delayed transfer of decalin to the acidic site for ring opening after dehydrogenation on the metal site.