摘要
考察了碱金属助剂对ＰｄＣｌ２－ＣｕＣｌ２ＡＣ催化剂上甲醇气相氧化羰基化直接合成碳酸二甲酯反应性能的影响及助剂的作用。结果表明：采用不同碱金属助剂时的碳酸二甲酯收率顺序为Ｋ＞Ｎａ＞Ｌｉ；ＫＯＡｃ助剂的主要作用是与ＰｄＣｌ２、ＣｕＣｌ２发生化学反应，促进催化活性位的形成；ＫＯＡｃ为助剂母体的效果明显好于ＫＣｌ母体；Ｋ助剂的最佳含量为２～３ｗ％；在反应温度Ｔ＝１５２℃，进料气体空速和液体空速分别为１４８３ｈ－１和４ｈ－１，进料ＣＯＯ２比为２８３时，对于Ｐｄ＝０６１ｗ％，原子比为ＰｄＣｕＫ＝１１４１４的ＰｄＣｌ２－ＣｕＣｌ２－ＫＯＡｃＡＣ催化剂，在６ｈ的运转时间内碳酸二甲酯的时空收率可达到３１７～３６１ｇＬ－ｃａｔｈ，甲醇的单程转化率为１４８～１６９％
The effect of different promoters on the reactive property of direct gas-phase synthesis of dimethyl carbonate (DMC) was studied at atmospheric pressure The functions of promoters were also investigated Experimental results show that the space time yield (STY) of DMC decreases with different alkali promoters in following order: K>Na>Li The optimal content of K promoter is 2～3w% Potassium acetate can enhance the reactivity of the oxidative carbonylation more markedly than potassium chloride The main function of promoter KOAc is to react with PdCl 2 and CuCl 2, and then promote the generation of the catalytic active sites Under the conditions of T=152℃, GHSV=1483h -1 and LHSV=4h -1 , CO/O 2=2 83, over PdCl 2-CuCl 2-KOAc/AC catalyst in which Pd% is 0 61% and the atomic ratio of Pd/Cu/K is 1/14/14, the STY of DMC attains 317～361g/L -cat h, and the conversion of methanol is 14 8～16 9% in the run time of 6h
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
1999年第4期319-322,共4页
Journal of Fuel Chemistry and Technology
基金
河北省博士基金
关键词
助剂
催化剂
碳酸二甲酯
甲醇
气相氧化
羰基化
alkali promoter, supported solid catalyst, dimethyl carbonate(DMC) synthesis, methanol, gas-phase oxidative carbonylation
