The COD of direct dyestuff wastewater was reduced from 1136 mg/L to 871 mg/ L after ozone bubbling treatment for 2 h The COD of direct dyestuff wastewater was reduced to 398 mg/L when the pH was changed to 12.0.
The COD ofdirect dyestuff wastewater was reduced from 1136 mg/L to 871 mg/L after ozone bubbling treatment for 2 h The COD of direct dyestuffwastewater was reduced to 398 mg/L when the pH was changed to12.0.