氧化羰基化甲醇觸媒之合成，結構，與催化反應研究

Preparation, Structure And Catalytic Properties Of Methanol Oxidative-Carbonylation Catalysts

陳世揚(Chen, Shihyang)

指導教授 ： 張仁瑞

國立中正大學/工學院/化學工程學系/碩士(2012年)

摘要

由連續式固定床反應器進行SiO2擔體Q50和HY型 zeolite CBV600與CBV760嫁接CuCl2與ZrO2金屬前驅物之催化實驗，分別命名為CuQ5、CuZQ5、CuCBV600及CuCBV760。將一氧化碳、氧及甲醇進行氧化羰基化反應合成碳酸二甲酯，在400psi、溫度為100℃、150℃、200℃及250℃底下操作。反應後之產物藉由GC-Mass鑑定成分，GC(FID)分析產物濃度，得到催化性能測試的結果發現觸媒之活性為CuCBV600 > CuCBV760 > CuQ5 > CuZQ5。利用FT-IR測定觸媒的酸基與使用粉末X射線繞射(PXRD)觀察觸媒結構之特性分析。從PXRD結果發現CuQ5與CuZQ5皆有形成CuCl2•2H2O及Cu(OH)Cl結晶相，而CuCBV600及CuCBV760只有形成Cu2Cl(OH)3結晶相，配合Rietveld method去計算結構參數與各晶相的結晶度。因為FT-IR與PXRD結果指出CuZQ5有較多的酸量與Cu(OH)Cl結晶度，因此推測在SiO2擔體上的催化活性為銅晶相扮演著比酸量更重要的角色。相反的，在HY zeolite擔體方面，CuCBV760有比CuCBV600較高的Si/Al 比、較低的酸量與較低的碳酸二甲酯選擇性，因此我們認為酸量在HY zeolite擔體上對觸媒催化活性扮演著相對重要的角色。

關鍵字

甲醇 ； 碳酸二甲酯 ； 氧化羰基化

並列摘要

SiO2, ZrO2/SiO2, and HY-zeolite supported copper catalysts, namely, CuQ5, CuZQ5, CuCBV600, CuCBV760, were used as catalysts for the preparation of dimethyl carbonate via oxidative carbonylation of methanol. A continuous fixed-bed reaction system was used to test the performance of these catalysts at temperatures ranging from 100℃ to 250℃ with total pressure of 400 psi. The species in the effluent of the reaction system were identified by GC-Mass and the concentration of these species was determined by GC. The tests indicated methanol conversion and selectivity to dimethyl carbonate for different supports is in the order of CuCBV600 > CuCBV760 > CuQ5 > CuZQ5. The structure and acidity of catalysts were characterized by synchrotron PXRD and FT-IR, respectively. PXRD results indicated that both CuCl2•2H2O and Cu(OH)Cl were observed for CuQ5 and CuZQ5, while only Cu2Cl(OH)3 for CuCBV600 and CuCBV760. The PRXD spectra were further refined by Rietveld method to determine the structure parameters and the fraction of each phase. The results indicated that CuZQ5 presents higher Cu(OH)Cl crystalline fraction and acid amount as opposed to CuQ5, suggesting that phase of Cu play much more important role in catalysis than that of catalyst acidity for the silica base supports. In contrast, for HY support, CuCBV760, of higher Si to Al ratio than CuCBV600, the Cu catalyst presented higher Cu2Cl(OH)3 fraction, lower acid amount, and lower selectivity to dimethyl carbonate, suggesting that the acidity play a significant role for the HY-supported catalysts.

並列關鍵字

methanol ； dimethylcarbonate ； oxidative-carbonylation

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