Degradation of 4-chlorophenol in aqueous solution by contact glow discharge electrolysis

In order to probe the degradation mechanism of 4-chlorophenol by contact glow discharge electrolysis(CGDE),the intermediate products and hydrogen peroxide formed during 4-chlorophenol degradation were determined by high performance liquid chromatography and colorimetric method,respectively.Experimental results show that a lot of hydrogen peroxide is formed during 4-chlorophenol degradation.Both the rates of 4-chlorophenol degradation and hydrogen peroxide formation speed up with the increase of electric current,which the increase of 4-chlorophenol initial concentration can decrease its removal rate and the formation rate of hydrogen peroxide.However,the absolute amount of 4-CP removed increases with the increase of 4-chlorophenol initial concentration.Iron salts have apparent catalytic effect on 4-chlorophenol removal,where the catalytic action of ferric ions is better than that of ferrous ions.Without iron salts,the primary intermediate products are hydroxylated phenols,while 4-chlorocatechol,benzoquinone and hydroquinone are major intermediate products with iron salts.