【摘要】 以正硅酸乙酯、聚乙二醇和乙醇等为主要原料,采用溶胶-凝胶法制备了固定化酶用的块状多孔S iO2,着重研究了不同热处理温度下材料的红外光谱、孔径分布和水热稳定性。结果表明:600°C热处理后可有效去除残余有机物,形成无定形硅氧网络结构,并得到细孔比表面积为392m2/g、孔容积为0.93 cm3/g、平均孔径为17 nm的圆柱状多孔S iO2;但经800°C以上热处理后多孔材料的体积密度显著增加、开口气孔率和比表面积急剧减小。600°C热处理的多孔材料在80°C热水中浸泡72 h后,氧化硅溶出率小于2%,细孔比表面积减少小于7%,显示出较好的水热稳定性。更多还原

【Abstract】 Porous SiO₂ blocks used as an enzyme carrier were prepared by polymerization of tetraethyoxysilane in the presence of polyethylene glycol via a solgel route.Infrared spectra,pore distribution and hot water durability were obtained for the materials prepared at different temperatures.Heat treatment at 600（°C） removed most organic residues and resulted in a vitreous structure with Si—O bonds;the porous silica had a pore volume of 0.93 cm³/g,specific surface area of 392 m²/g,and average pore diameter of 17 nm.Density of the porous blocks was much higher while the porosity and specific surface area were substantially lower when the heating temperature was over 800（°C）.The porous blocks heated at 600 （°C） was durable in hot water;after immersed in water at 80 （°C） for 72 h,its weight loss was <2% and reduction in specific surface was <7%.更多还原