CuCl/phen/NMI in Homogeneous Carbonylation for Synthesis of Diethyl Carbonate: Highly Active Catalyst and Corrosion Inhibitor

• Published in: Industrial & engineering chemistry research Vol. 48; no. 24; pp. 10845 - 10849
• Main Authors: Xiong, Hui, Mo, Wanling, Hu, Jianglin, Bai, Rongxian, Li, Guangxing
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 16.12.2009
• Subjects: Applied sciences; Catalysis; Catalytic reactions; Chemical engineering; Chemistry; Exact sciences and technology; General and physical chemistry; Kinetics, Catalysis, and Reaction Engineering; Reactors; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Carbonylation; Catalyst; Corrosion inhibitor
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/ie901139e

The effects of N-donor ligands on CuCl-catalyzed oxidative carbonylation of ethanol were investigated. It was found that 1,10-phenanthroline (phen) and N-methyl imidazole (NMI) exhibited a synergic effect on the catalytic activity. Catalytic efficiency of the CuCl system was enhanced dramatically, and corrosion of the reaction system was effectively inhibited when phen and NMI were simultaneously used as the ligands. Under the reaction conditions of c CuCl = 0.2 mol/L, n Cu:n phen:n NMI = 2:1:1, T = 393 K, P = 2.4 MPa with P CO/P O2 = 2:1, and time = 3 h, conversion of ethanol and selectivity to diethyl carbonate (DEC) were 15.2% and 99.0%, respectively. As compared to pure CuCl, the catalytic activity of CuCl/phen/NMI is much higher (3.6-fold). Furthermore, the high catalytic activity could be kept for a long time of service during the reaction. Corrosion of CuCl was also inhibited by using phen and NMI as ligands. For example, the inhibition efficiencies of CuCl/phen/NMI catalyst system on stainless steel 304 and Hastelloy 5923 were 98.1% and 98.2%, respectively.