Salt-mediated Synthesis Ot SBA-15Mcsostructures

Mesoporous materials is generally refers to the orderly porous materials which has thepore size in2~50nm range. Porous materials show regular pore size distribution and alarge BET surface area. However, mesoporous passes is constructed of amorphous hole wall,consequently compared with the microporous molecular sieve, mesoporous materials showlow hermal and mechanical stability. At the end of the twentieth century, Zhao et.synthesized thick wall of SBA-15mesoporous molecular sieve by using pluronic as atemplate which improve hermal and mechanical stability of molecular sieve in a certaindegree. The mesoporous molecular sieve SBA-15has been received much attention in thefields of catalytic chemistry and adsorption-separation, due to the advantages of highsurface area, ordered and tunable pore structure, high thermal and hydwthermal stability andfacile modification of surface properties. In spite of the weak acidicity, SBA-15can still beused as acidic catalyst when some non-silicon atoms, such as Al, P, Zr, were introduced intoits skeleton and, thus, some acid centers were obtained. In this thesis, SBA-15was firstlyprepared, and then SBA-15has modified by Zr doping and SH loading. We have obtainedcertain innovation in the preparation method.The main research work is as follows:1. Highly ordered mesoporous ZrSBA-15silica with ordered morphology wassynthesized through a hydrothermal route by using pluronic P123as a template,tetraethyl-orthosilicate as a silica source, by the synergy of zirconium oxchloride andsodium choride. The as-synthesized materials were characterized by transmission electronmicroscopy (TEM), scanning electron.microscopy (SEM), fourier-transform infraredspectroscopy (FTIR), N2adsorption/desorption isotherms,and LXRD. The results demonstr-ate that ZrSBA-15materials have highly ordered two-dimensional hexagonal mesoporousstructure similar to conventional SBA-15.2. Mesoporous ZrSBA-15silica with ordered morphology was synthesized through ahydrothermal route by using pluronic P123as a template, tetraethyl-orthosilicate as a silica source,MPTMS as the organic functional component,by the synergy of zirconium oxchlorideand sodium choride and salt effect. The as-synthesized materials were characterizedcomprehensively by transmission electron microscopy (TEM), scanning electron.microscopy(SEM), fourier-transform infrared spectroscopy (FTIR), N2adsorption-desorption isotherms,and LXRD. Results show that the functionalized mesoporous materials till showed regularpore structure.