摘要
以醋酸铜为前驱物，采用浸渍法负载后进行热处理使醋酸铜热解，获得了负载型无氯Cu2O／AC（活性炭）催化剂，并通过催化甲醇直接气相氧化羰基化合成碳酸二甲酯（DMC）．在氮气和惰性气体气氛下，一水合醋酸铜Cu（CH3COO）2·H2O在30～450℃范围内产生3个失重过程，其中在150—300℃范围内Cu（CH3·COO）2热解生成Cu2O；而在300～450℃范围内生成单质Cu．在200～350℃范围内，将Cu（CH3COO）2·H2O／AC加热处理4h后，催化剂上逐步形成了Cu2O，到350℃时，水合醋酸铜几乎全部转化为Cu2O，并有极少量单质Cu形成．在300～350℃热处理4h后，催化剂中铜主要以Cu2O形式存在，并表现出良好的氧化羰基化催化活性．在n（CO）：n（MeOH）：n（O2）=4：10：1及SV=5600h^-1条件下，于300℃热处理4h所制备的催化剂的甲醇转化率达到6．21％，DMC的时空收率为128．16mg·g^-1·h^-1，选择性为64．26％．
The chloride-free Cu2O/AC catalyst was prepared via pyrolysis of copper acetate supported on active carbon Cu （CH3 COO）2/AC and used to catalyze vapor-phase oxycarbonylation of methanol to dimethyl carbonate（DMC）. The Cu （CH3COO）2AC precursor was prepared by the incipient wetness impregnation. When Cu（CH3COO）2·H2O was heated from 30 ℃ to 450 ℃ under inert nitrogen atmosphere, it decomposed successively to Cu（ CH3COO） 2, Cu2O and Cu, corresponding to three chemical processes. Cu2O was obtained at 150-300 ℃ heating temperature, and Cu was formed at 300-450 ℃. When Cu（CH3COO）2·H2O/AC was heated at 200-350 ℃ for 4 h, Cu2O was gradually formed on the surface of AC. The Cu2O/AC catalyst with predominant Cu2O and only a little Cu was obtained when Cu（CH3COO）2·H2O/AC heated at 350 ℃ for 4 h. It was observed that the Cu2O/AC catalyst heat-treated at 300-350 ℃ for 4 h exhibited very high catalytic activity for methanol oxycarbonylation. On the conditions of n （CO） ： n （MeOH） ： n （ O2 ） = 4：10：1 and SV = 5600 h^-1, and in the presence of Cu2O/AC catalyst prepared at 300 ℃ for 4 h, the methanol conversion, the space time yield and the selectivity of DMC was reached 6. 21%, 128.16 mg·g^-1· h^-1 and 64.26%, respectively.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2009年第10期2024-2031,共8页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:20576085)
国家“九七三”计划(批准号:2005CB221204)资助
