Surface And Functional Modification Of Mesoporous Silicas And Its Application In Immobilization Of Trehalose Synthase And Separation Of Butanol

Silica has better biocompatibility.Served as one of the inorganic materials,silica is easy to be modified and the operation process is simple.Silica has a serious of porous channel with various size(micropore,mesoporous,macroporous).Silica also has other advantages,such as a large specific surface area,large size distribution and good mechanical properties.On the surface of Silicalite-1,hydroxy is easy to be activated and it provide a serious possible of subsequent chemical modification.Then,silica has a good application prospect.Butanol have many advantages in the industrial circle.Because served as a potential alternative energy sources,butanol has attracted more and more attention.Trehalose is used to serve as a protective agent of enzyme,vaccine and cell.Our group has prepared the high stability trehalose(50℃)synthase by recombinat E.Coli.In order to realize the continuous catalytic of Trehalose and improve the stability of enzyme,the enzyme is immobilized by silica.The main research results are showed following:This experiment select adsorption as the separation method,then the adsorbent is one of important things in the separation process.The commercial silicalite-1 is selected to serve as the adsorbent and silicalite-1 is modified by functional group to improve the adsorbing capacity of adsorbent.Dodecafluoroheptyl-propyl-trimethoxysilane and(3-Aminopropyl)trimethoxysilane are used to modify silicalite-1,then the hydrophobic/hydrophilic layer is constructed on the surface of silicalite-1.For the construction of hydrophobic layer,the functional material has decrease the adsorption capacity of water and increase the adsorption capacity of butanol.In order to improve the dispersive capacity of hydrophobic silica,a hydrophilic modification is proceeded.For this hydrophobic/hydrophilic layer is built,the layer has not influenced the adsorption rate of butanol and the thermal stability is good.In the adsorption experimental of butanol,the adsorbing capacity of functional silicalite-1 is increased by 50%.Firstly,the commercial silicalite-1 is served as a carrier and modified by epoxy silane,then the modified silicalite-1 is used to immobilized by enzyme and the immobilized enzyme can recycle 5 times.Secondly,Hexadecyltrimethylammonium chloride is served as a template,Tetraethyl orthosilicate and Glycidyl3-(trimethoxysilyl)propylethe are selected as a silicon source,then a nano-sized carrier is prepared and used to immobilized enzyme.After 10cycles,the immobilized enzyme can retain 80%of its original catalytic capacity.What we want to do is using the functional silica to realize the separation of butanol and catalytic of maltose.