Carbonylation at Atmospheric Pressure in Strong Acid

Abstract

Rhodium compounds are an excellent catalyst in the synthesis of acetic acid, ethanol and ethyleneglycol from synthesis gas. As the amount of rhodium is not enough, research of other catalysts is necessary.
The synthesis of ethylene glycol via glycolic acid was studied. The synthesis of glycolic acid was improved by using copper or silver carbonyl co-catalyst. Carbonylation of formaldehyde proceeded at atmospheric pressure of CO at 20 °C without side reactions by using copper or silver catalyst in H₂SO₄, BF₃-H₂O, and HF. Rate constants of carbonylation increased 30 times in the presence of co-catalyst. The rate decreased with the decrease of acid concentration. Ethyleneglycol was obtained by a hydrogenation of glycolic acid using Co-Cu, Co-Cr, Co-Zn-Cu, or RuO₂ catalyst.
Copper and silver carbonyl catalysts were applied to the carbonylation of olefins, alcohols, and saturated hydrocarbons at atmospheric pressure of CO and room temperature. Tertiary-carboxylic acids were obtained in high yields.