Degradation of basic and acid dyes in high-voltage pulsed discharge

•We researched in a gas–liquid series high-voltage pulsed discharge reactor.•Comparing the degradation of monocomponent basic dyes, acid dyes, and the mixture of basic or acid dyes.•Nearly complete bleaching in 21 minutes for all monocomponent dye, 90% for mixtures.•The initial pH and conductivities had significant effect on the degradation of both acid and basic dyes.

The degradation of monocomponent basic dyes (Basic Orange, Methylene Blue), acid dyes (Methyl Orange, Eosin Yellowish) and the mixture of basic and acid dyes was investigated in a gas–liquid series high-voltage pulsed discharge reactor. The decolourization efficiency of the reactor was higher; nearly complete bleaching was achieved in 21 min for all the monocomponent dyes and over 90% bleaching for the mixtures. The total organic carbon removal of the monocomponent was 32% for acid dyes and 22% for basic dyes; the mineralization of mixtures was lower than that of single dyes. On comparing with the single dyes, the energy yield significantly increased when this reactor was used to treat the mixtures. The initial pH and conductivities had significant effect on the degradation of both acid and basic dyes.