Study on the formation and role of copper chloride hydroxide in the oxidative carbonylation of methanol to dimethyl carbonate

The synthesis of dimethyl carbonate by oxidative carbonylation of methanol over CuCl/SiO 2 -TiO 2 catalysts has been investigated in a slurry reaction system. The γ-Cu 2 (OH) 3 Cl crystals were detected by X-ray diffraction on the catalysts after reaction. It was revealed that γ-Cu 2 (OH) 3 Cl was formed by CuCl reacting with O 2 and by-product water. The catalytic tests showed that γ-Cu 2 (OH) 3 Cl was largely inactive for this reaction, may be attributed to its high stability that resisted the Cu + /Cu 2+ redox cycle.