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Carbonate is an important compound in organic synthesis, dyeing, electrochemical and petrochemical and other fields have a wide range of applications, so carbonate green, efficient synthesis of recent years become a research hotspot. The ionic liquid by virtue of its own characteristics, such as high pressure can amount of dissolved CO 2 , for epoxide cycloaddition with good catalytic effect, the catalyst can be reused, so as to make the ionic liquid In carbonate synthesis become a research hotspot. But liquid ionic liquid is present, higher prices, a large amount of catalyst is not easy to separation and purification and other shortcomings, so by adsorption or grafting immobilization method attempts to ionic liquid supported on an inorganic porous material or organic polymer materials, manufacturing much-phase catalyst, the ionic liquid properties transferred to the heterogeneous solid catalyst, as the current on ionic liquids research a hot area. In this paper, the cationic polymerization of the imidazolium cation binding to the inorganic silica gel, and then through the ion exchange method, get a different anions immobilized ionic liquid. By IR, carbon spectra NMR, elemental analysis by means of immobilization of [mim] Cl, [mim] BF4, [mim] PF6 qualitative analysis to determine its structure. Through the reaction influencing factors investigated, drawn simply using immobilized ionic liquid catalyst, the activity was significantly lower than the traditional homogeneous reaction results, propylene oxide (PO) conversion rate was only 67.74%. According to the literature, co-catalyst can increase the PO conversion rate, so experiment to examine more cocatalysts this reaction, obtained cocatalyst AlCl 3 formation of the catalyst system, can improve the PO conversion rates. Experimental finally get optimum catalytic reaction conditions: catalyst [mim] Cl 0.3g, co-catalyst AlCl 3 0.03g, propylene oxide (PO) 2.0g, CO 2 pressure 3MP, reaction temperature 120 ℃, reaction time 4h. In this condition, PO conversion rate can reach 99.12%, propylene carbonate (PC) selectivity of 99.1%. On the catalytic system reusability study found that the catalytic system reused four times, the activity was not significantly reduced. This article and this immobilized ionic liquid catalyst for one-step synthesis of dimethyl carbonate catalytic activity to inspect, test through the reaction influencing factors of investigation, draw a suitable catalytic reaction conditions: catalyst [mim] BF4 0.75g of catalyst sodium 0.25g, methanol 200mmol, PO 25mmol, CO 2 Pressure 4MP, reaction temperature 120 ℃, reaction time 6h. In this condition, PO conversion of 85.14% of dimethyl carbonate (DMC) selectivity and yield were 45.99% and 39.16%. On the catalytic system reusability study found that the catalytic system reused four times, the activity was not significantly reduced.
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