Huls developed this process to industrial maturity and started up
a smaller production unit in West Germany. There are two plants
operating in Rumania using the same process with a total
capacity of 8000 tonnes per year. Tertiary amines, quaternary
ammonium salts or active carbon impregnated with NaOH are
all suitable catalysts. The process is conducted at 160-200°C
and 70 - 100 bar. A 97 - 98% yield is obtained. Texaco and Dow
produce ethylene carbonate commercially in the USA.