| Summary: | 碩士 === 國立臺灣大學 === 化學研究所 === 96 === Short-channel SBA-15 with three different pore diameters (7.0, 8.2, and 9.2 nm) were synthesized by hydrothermal reaction at different temperatures with the aid of a
small amount of Zr(IV) in the synthesis solution. The mesoporous silica with various functional groups including phenol, thio, carboxylic acid, amino, and octyl were also
prepared. They were used as the supports for lipase (from porcine pancreas) immobilization. The large pore facilitated the adsorption of the enzyme. The optimal
pH value for immobilization of lipase changed with the functional groups, and pH 5 is the best for pure siliceous SBA-15 and those functionalized with phenol, thiol, and
carboxylic acid while pH 7.4 is the best for amino functionalized SBA-15. In catalytic hydrolysis of triacetin, highest catalytic activity was achieved at pH 7.4 and in the presence of a small amount of hydrophobic co-solvent.
Among the functionalized SBA-15 materials, the one functionalized with amino or octyl groups gave the highest catalytic activity. It is attributed to the amino group
could keep in lipase at pH 7.4 through the electrostatic interaction and the octyl group facilitates the approach of triacetin to the active sites of lipase.
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