Iron-catalyzed wet air oxidation of biomethanated distillery wastewater for enhanced biogas recovery.

In the present work, catalytic wet air oxidation (WAO) technique was applied to biomethanated spent wash from a local sugar factory. This wash water exhibited high biological oxygen demand (BOD = 8100 mg/L) and chemical oxygen demand (COD = 40,000 mg/L). The objectives of oxidative pre-treatment were two-fold, viz.