發(fā)布時間：2018-12-11 17:09

【摘要】：本文研究了乙二醇與甲醇一步氧化酯化制備乙醇酸甲酯的反應(yīng)。首先進行催化劑的篩選實驗,得到了具有良好催化活性的負載型Au/Al2O3催化劑,通過對反應(yīng)條件的研究,確定了乙醇酸甲酯的最佳合成工藝條件。 在催化劑的篩選階段,首先考察了一系列Keggin型P-Mo-V雜多酸催化劑。實驗結(jié)果表明,雜多酸催化劑對乙二醇與甲醇的氧化酯化反應(yīng)沒有催化活性。采用共沉淀法制備負載型Au/Al2O3催化劑,考察了不同Al203載體、Au負載量、催化劑制備過程中的焙燒溫度等對反應(yīng)轉(zhuǎn)化率和選擇性的影響。選用比較大的孔徑Al203載體、Au負載量為0.5-1.0wt%、經(jīng)過300℃焙燒2h制備的Au/Al2O3催化劑,顯示出良好的催化活性和選擇性。 反應(yīng)條件的研究結(jié)果表明,反應(yīng)溫度、壓力、氧氣濃度和原料配比等對反應(yīng)轉(zhuǎn)化率和選擇性影響很大。適宜的反應(yīng)條件為：反應(yīng)溫度120℃、反應(yīng)壓力0.45MP、氧氣與氮氣的分壓比1：1-1：2、原料乙二醇和甲醇摩爾比為1：10,乙二醇的轉(zhuǎn)化率和生成乙醇酸甲酯的選擇性都達到80%以上。
[Abstract]:The synthesis of methyl glycolate by one-step oxidation esterification of ethylene glycol and methanol was studied in this paper. At first, the supported Au/Al2O3 catalyst with good catalytic activity was obtained by screening the catalyst. The optimum synthesis conditions of methyl glycolate were determined by studying the reaction conditions. In the screening stage, a series of Keggin type P-Mo-V heteropoly acid catalysts were investigated. The experimental results show that the heteropoly acid catalyst has no catalytic activity for the oxidative esterification of ethylene glycol and methanol. Supported Au/Al2O3 catalysts were prepared by coprecipitation method. The effects of different Al203 support, Au loading amount and calcination temperature on the conversion and selectivity of the catalyst were investigated. The Au/Al2O3 catalyst prepared by calcination at 300 鈩，

本文編號：2372918