A boron doped diamond (BDD) electrode was employed in an electrochemical reactor to oxidize the phenolic content of Jordanian olive mill wastewater. The BDD anode was fabricated using the hot filament chemical vapor deposition on niobium and the morphology of the BDD electrode was characterized by using an atomic force microscope. Then, electrolysis batch runs were carried out in laboratory scale to test the effect of different process parameters namely, initial chemical oxygen demand (COD) load (72.9, 33.8, and 0.18 g/L), addition of Na2SO4 as supporting electrolyte, and adding NaCl along with Na2SO4, on the efficiency of the treatment process. The results were reported in terms of COD, color and turbidity removal, and pH variation. The experiments revealed that electrochemical oxidation using BDD significantly reduced the COD by 85% with no supporting electrolytes. It was observed that adding Na2SO4 with NaCl brought the COD removal to higher than 90% after 7 hours of treatment for COD loads of 72.9 and 33.8 g/L and after 2 hours for a COD load of 0.18 g/L. Likewise, color was completely removed regardless of the initial COD load. The turbidity for samples with 72.9 and 33.8 g/L as COD load reached a minimal value of 2.5 and 1 NTU respectively.
- advanced oxidation processes
- boron-doped diamond electrode
- electrochemical oxidation
- olive mill wastewater
- phenolic compounds
- First received 28 March 2016.
- Accepted in revised form 15 July 2016.
- © IWA Publishing 2016