载钯硅藻土制备及吸/放氢性能分析

采用(NH4)2Pd(NO3)4浸渍-热分解法制备了钯含量为44.5%±0.1%的载钯硅藻土(Pd/K)颗粒,对材料进行了BET、XRD、X荧光、冷热循环分析,测定了常温下的吸/放氢(氘)等温线。结果表明,Pd/K经多次吸/放循环后有轻微的粉化;随循环次数的增加,粒径分布趋于稳定。与纯钯相比,吸/放氢(氘)等温线呈现坪台压力上升,坪斜增加,吸氢容量减小的特点;同一温度下,氕的滞后效应明显大于氘;温度升高,滞后效应减小。

Preparation of Palladium Coated on Kieselguhr and Analysis of Its Hydrogen Absorption/Desorption Properties

Palladium coated on kieselguhr(Pd/K) particles was prepared by dipping-thermo decomposition of(NH_4)_2Pd(NO_3)_4.Full characterization of the sample was performed by using BET,XRD,X-fluorescence spectroscopy and cold-heat recycling.Hydrogen(deuterium) absorption(desorption) isotherms at room temperature were measured.Results show that Pd/K is cracked down to some degree after repetitious cooling and heating,and the cracking slows down with cycles.Compared with data of pure Pd,the isotherms of protium(deuterium) absorption(desorption) were characterized by higher plateau pressure,larger plateau slope,and smaller hydrogen solubility.At the same temperature,the hysteretic effect of protium desorption is remarkably larger than that of deuterium.For both protium and deuterium desorption,the hysteretic effect is reduced with temperature increasing.