本研究旨在探討CuCl2/C和CuCl2-PdCl2/C兩觸媒的甲醇加氧羰基化的活性，反應是在一個的連續流動的微型反應器中進行，壓力為常壓，主要反應溫度為160℃，進料中有CH3OH、CO、及O2，目標產物為碳酸二甲酯。
實驗的結果顯示，CuCl2/C為具甲醇加氧羰基化活性之觸媒，CuCl2的含量在14.0wt%時觸媒的活性最高。氯化鈀(PdCl2)有活性促進的效果，添加於CuCl2/C可增加其的活性，碳酸二甲酯的選擇率也可因而提高，最佳的氯化鈀添加量為0.5 wt%，過量的添加反而造觸媒活性的下降。
反應的產率與進料的組成有關，達到最大產率的最佳進料組成與所使用的觸媒有關，在固定O2於8%之引爆安全濃度下，10%CuCl2/C觸媒的最佳CH3OH/CO進料比為1:12，在此進料比下，可在40%甲醇轉化率下，達到87%的碳酸二甲酯選擇率；以CuCl2(10%)-PdCl2(0.5%)/C為觸媒時，在相同的反應條件下，最佳的CH3OH/CO進料比為1：6.6，在此進料比下，可在38%甲醇轉化率下，達到95%的碳酸二甲酯選擇率。
CuCl2/C及CuCl2-PdCl2/C觸媒在反應時皆有失活現象，前者較嚴重，由XRD的實驗結果發現，反應後的CuCl2/C觸媒中有多種含二價銅的結晶物出現，但是在反應後的CuCl2-PdCl2/C觸媒中並沒有發現類似的情形，說明了CuCl2/C較易失活的原因，而添加PdCl2有防止銅聚集的作用。另於ESCA的分析結果發現，觸媒上的銅，在反應前後皆為二價，氯含量則大幅減少，EDX實驗結果也證實有此現象，所以觸媒活性衰退應是與銅晶體的成長及氯的流失有關。

Abstract

The aim of this investigation is to examine the activities of CuCl2/C and CuCl2-PdCl2/C catalysts in the oxidative carbonylation of methanol. The reactions were carried out in a continuous flow micro-reactor under atmospheric pressure and at 160C. The feed contained methanol, carbon monoxide and oxygen. The desired product was dimethyl carbonate.
The experimental results show that both CuCl2/C and CuCl2-PdCl2/C are active for the reaction. The most active CuCl2/C catalyst contains 14 wt% CuCl2. The activity of CuCl2/C may be enhanced by the incorpo-
ration of palladium chloride. The incorporation increases not only the activity of the catalyst but also the selectivity of dimethyl carbonate. The optimum amount of palladium chloride in CuCl2-PdCl2/C catalyst is 0.5 wt%. Excess amount of the chloride will only make the catalyst less active.
The yield of dimethyl carbonate in the reaction is related to the feed composition. The optimum feed composition for maximum yield depends on the catalyst used. With the oxygen contain being limited to 8% to avoid explosion, the optimum feed ratio of CO/CH3OH for 10% CuCl2/C is 12. Under the ratio, the reaction may have 40% methanol conversion and 87% dimethyl carbonate selectivity. When CuCl2-PdCl2/C is used as the catalyst, the optimum ratio becomes 6.6. The reaction under the ratio may have 38% conversion and 95% selectivity.
Deactivation was found in either CuCl2/C or CuCl2-PdCl2/C and the situation for CuCl2/C is more severe. The growth of crystalline copper compounds, as found by XRD, during the reaction is one of the causes for the deactivation. CuCl2-PdCl2/C catalyst has less of the crystalline compounds indicating PdCl2 is capable of preventing the growth of the crystals. Both ESCA and EDX analyses have shown that the chlorine content in the catalyst is significantly reduced during the reaction. Therefore, the loss of chlorine may be another reason for the deactivation.

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