Preparation and Properties of Ionic Liquids Supported on Organic-Inorganic Hybrid Porous Materials
|School||Dalian University of Technology|
|Keywords||Porous materials Sol-gel Ionic liquid Immobilization Knoevenagelcondensation|
Ionic liquids as a new green solvent and catalyst, make it become organic synthesis,separation and analysis, and functional materials such as one of the hot areas of research, butthe cost is higher, use large, easy catalyst separation disadvantages limit its wide application.There is now one of the ways to solve the problems is to load ionic liquids into the inorganicporous materials or organic polymer materials, the system was "quasi-homogeneous" catalyst,thereby transferring the properties of ionic liquids to the heterogeneous solid catalyst, thetransition from "homogeneous" to " heterogeneous " of the transformation. In view of this, inthe preparation process, this thesis mesoporous silicon oxide as the carrier, the ionic liquidload to the porous material, and selection of a more comprehensive characterization methodssuch as BET, SEM, TEM, FT-IR, TG-DTG, etc. of ionic liquids in the channels ofmesoporous silica micro-environment and interaction between rule, while the immobilizedionic liquid for the Knoevenagel condensation reaction in order to study its catalytic activity.The main work of this thesis:1. PMHS as the structure directing agent to synthesize new porous materials. Hybridsiliceous xerogels with superior hydrophobic frameworks have been facilely prepared usinglinear polymethylhydrosiloxane (PMHS) and tetraethylorthosilicate (TEOS) as silicaprecursor via a one-step synthesis approach, It was shown that, The sample exhibitsdeveloped structural characteristics and excellent hydrophobicity. This kind of hydrophobicxerogels may be potential adsorbents for cleaning up spills of oil or organic chemicals on thewater surface and toxic organic pollutants in water at very low concentrations.2. Immobilization of ionic liquid by grafting method.The1-methyl-3-[3-(trimethoxysiyl)propyl]imidazolium chloride, which contains the cation of the ionic liquid, was prepared andgrafted on the surface of the porous materials. obtained functional ionic liquid/silicon oxidecomposite materials. and indicated that it is better to load to the ionic liquid on porous silicon;At the same time, the composite materials for Knoevenagel condensation reaction, the resultsshow that the catalyst shows excellent catalytic performance, and4times in the recycling rate is still over84%yield.3. Immobilization of ionic liquid by sol-gel method. By using mixture containing1-methyl-3-[3-(trimethoxysiyl)propyl]imidazolium chloride and TEOS as silicon source, themesoporous hybrids were prepared via sol-gelroute. and indicated that it is better to load tothe ionic liquid on porous silicon; And pore size distribution is relatively narrow. At the sametime, This composite material used for Knoevenagel condensation reaction, the results showthat the catalyst shows excellent catalytic performance, and4times in the recycling rate isstill over78%yield.