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采用常规体积吸附装置测定了77、195、293K和7MPa的条件下氢在A、X及ZSM-5沸石上的吸附特性和吸附容量．所有的氢吸附等温线基本符合Ⅰ型等温线,但在77K,压力为2-5MPa的等温线上观察到了超临界高压吸附所特有的最大吸附量．从等温线确定了等量吸附热并讨论了其影响因素．根据骨架结构和所含阳离子类型的差异,各种沸石表现出不同的氢吸附量．其中NaX沸石在77K/4MPa下的重量储氢分数为2．55％,是该实验中所测得的最高吸附量．CaA、NaX和ZSM-5沸石的氢吸附量与其比表面积成正比,这与沸石中的可用空穴容积有关．然而NaA和KA沸石不存在这种线性关系．实验中还观察到,NaA与KA沸石间出现氢吸附量的临界值是由KA沸石中较大的阳离子堵塞效应引起的．该实验将吸附质分了的动力学直径与沸石主晶孔的有效直径之比用于判断物理吸附中的堵塞效应．
Adsorption characteristics and adsorption capacities of hydrogen on zeolites A, X and ZSM-5 were measured at 77, 195, 293 K and 7 MPa using conventional volumetric adsorption equipment. All of the hydrogen adsorption isotherms are basically in line with the type I isotherms, but the maximum adsorption capacity characteristic of supercritical pressure adsorption was observed on the isotherms of 77K and pressure of 2-5MPa. Equal amount of adsorption heat was determined from the isotherm and its influencing factors were discussed. Depending on the skeletal structure and the type of cations contained, the various zeolites exhibit different amounts of hydrogen uptake. Among them NaX zeolite under 77K / 4MPa weight hydrogen storage fraction of 2.55%, is the maximum adsorption capacity measured in this experiment. The hydrogen adsorption capacity for CaA, NaX and ZSM-5 zeolites is proportional to their specific surface area, which is related to the available void volume in zeolites. However, there is no such linear relationship between NaA and KA zeolites. It has also been observed experimentally that the critical hydrogen adsorption capacity between NaA and KA zeolites is due to the larger cation plugging effect in KA zeolites. In this experiment, the ratio of the kinetic diameter of the adsorbed mass to the effective diameter of the main pores of the zeolite was used to judge the clogging effect in the physical adsorption.