【摘要】 采用程序升温还原方法制备了TiO2负载的晶态N i2P催化剂。用X射线衍射(XRD)及低温N2吸附(BET)等技术对样品的物相、比表面积等性质进行了表征。以苯气相加氢为模型反应考察了N i2P/TiO2催化剂加氢性能,并对N i2P负载量、前驱体中P的质量分数对催化剂的物相及性能的影响进行了研究。实验结果表明,TiO2负载的晶态磷化镍催化剂上,N i2P是主要物相。N i2P/TiO2催化剂对苯加氢反应具有较高的活性、选择性以及良好的稳定性能。N i2P/TiO2制备对催化剂的性能有影响。N i2P负载量增加,催化剂的活性先升高后降低,N i2P负载量为12%时催化剂活性较高。催化剂前驱体中P的质量分数越高,制备出的催化剂对苯加氢反应的稳定性越好,但随前驱体中P的质量分数增加,催化反应的活性先升高,后降低。与N i2P/SiO2比较,N i2P/TiO2催化剂具有较高的活性和稳定性。更多还原

【Abstract】 Transition metal phosphides have recently been reported as a new class of high-activity hydrodesulfurization（HDS） and hydrodenitrogenation（HDN） catalysts.Among them,Ni₂P has better HDS and HDN activity.The surface area of unsupported Ni₂P catalysts is rather low（< 1m²/g）.To increase the active surface area,the dispersion of Ni₂P on a high-surface support is needed.SiO₂ is widely used as support of the Ni₂P catalysts. TiO₂ is commonly used as support of catalysts.It can cause strong interaction with metal,that facilitates disperse of active components on its surface.In this paper,a series of supported Ni₂P catalysts on TiO₂ were prepared via temperature-programmed reduction.The structure characteristics of samples have been characterized by means of X-ray powder diffraction（XRD）,N₂ adsorption（BET） and temperature-programmed reduction（H₂-TPR）.Benzene hydrogenation was chosen as a model reaction to investigate the influences of Ni loading,initial Ni/P mole ratio.Results showed that Ni₂P was the main phase on the TiO₂ supported catalysts.Ni₂P/TiO₂ catalysts had high activity with 100% cyclohexane selectivity and excellent stability in benzene hydrogenation reaction.The preparation factors had great effects on the activity of benzene hydrogenation reaction.With the increase of Ni₂P loading,the activity of the Ni₂P/TiO₂ catalyst increased firstly and then decreased.Benzene conversion reached a maximum with Ni₂P loading of about 12%.The activity and stability of the Ni₂P/TiO₂ catalysts were also affected profoundly by the initial phosphorus content.With the increase of the initial P/Ni mole ratio,the reaction stability is better,but the steady activity increased firstly and then decreased.In comparison with Ni₂P/SiO₂,Ni₂P/TiO₂ catalysts had much better activity and stability in benzene hydrogenation reaction.更多还原