Removal of Organic Pollutant in Sulfonated Drilling Wastewater with Novel Solar-Assisted Catalytic Oxidation Process

The chemical oxygen demand was over standard seriously due to residual organic additives in sulfonated drilling wastewater, especially sulfonated phenolic resin with hardly degradable chemical structure. The novel solar-assisted catalytic oxidation process was developed to remove the organic pollutants in sulfonated drilling wastewater. The factors including irradiation light source, oxidant, Fe2+, were investigated. The results showed that, solar has more catalytic effects than UV on H2O2-K2S2O8/Fe2+system, H2O2- K2S2O8/Fe2+system was more effective in degrading organic pollutants than H2O2/Fe2+and K2S2O8/Fe2+, in which the synergies occurred between H2O2and K2S2O8in the solar-assisted catalytic oxidation process. The removal amount of organic pollutants was increased with the dosage of Fe2+additon. With the catalytic oxidation process developed, the COD was reduced to 114.4 mg·L-1. Meanwhile, the sulfonated phenolic resin was completely destroyed, and heavy metal was decreased significantly.