掺杂金属介孔分子筛MCM-48的合成及储氢研究

Synthesis and Hydrogen Storage Properties of Metal Doped Mesoporous MCM-48

以十六烷基三甲基溴化铵为模板剂,正硅酸四乙酯为硅源,在碱性条件下一步法水热晶化合成掺杂金属的介孔分子筛MCM-48。采用XRD、N2吸附脱附对产品进行结构表征,结果表明金属掺杂的介孔分子筛仍保持了三维立方介孔结构,但有序性略有降低,比表面积减小。对样品进行储氢性能研究发现,纯的MCM-48氢吸附量随温度的降低而增加,在0.2MPa、-25℃时氢吸附量达0.678 8%;金属掺杂介孔分子筛中,Ni、Fe、Pd有利于提高储氢量,Zr、Mg反而使氢吸附量减小,其中Ni-MCM-48在0.2MPa、-10℃时氢吸附量最高,达到0.772 0%。

With cetyltrimethylammonium bromide as mouldboarding agent,tetraethyl orthosilicate as silica source,by adding metal salts solution directly into the process of synthesis which is the first step,we can get metal doped mesoporous molecular sieve MCM-48 through hydrothermal synthesis in alkaline conditions.XRD,N2 adsorption-desorption can characterize the structure of some product,and the results show that the metal doped mesoporous molecular sieve maintained the three-dimensional cubic mesoporous structure,but the consistency was slightly lower and the specific surface decreased.Research on the hydrogen storage capability of this mesoporous molecular sieve suggests that the amount of hydrogen adsorption of pure MCM-48 increases with temperature decreasing.At 0.2 MPa,-25 ℃,the amount of hydrogen adsorption can reach 0.678 8%;In metal-doped mesoporous molecular sieve,Ni,Fe,Pd can help improve the hydrogen storage capacity,Zr,Mg negatively will reduce the amount of hydrogen adsorption,of which Ni-MCM-48 gets the highest amout of hydrogen adsorption at 0.2 MPa,-10 ℃,reaching 0.772 0%.