JNGC 16-2007-273

Carbon Dioxide Fixation Method for Electrosynthesis of
Benzoic Acid from Chlorobenzene

Carbon dioxide fixation technique was developed as an alternative dechlorination method of
chlorobenzenes. Electrolysis of chlorobenzene was carried out in a one-compartment cell fitted with an aluminium
anode and a platinum cathode. Electrolysis in N,N-dimethylformamide (DMF) solution containing
0.1 M of tetrapropylammonium bromide (TPAB) at 0 ℃, 100 ml/min of CO2 flow rate and 120 mA/cm2
of current density was found to be the optimum conditions of this electrocarboxylation, which gave 72%
yield of benzoic acid from chlorobenzene. These conditions were then applied to 1,2-dichlorobenzene and
1,3-dichlorobenzene in order to convert them to their corresponding benzoic acids.