Preparation and study of a new type of Fe-C microelectrolysis filler in oil-bearing ballast water treatment.

In the transportation of petroleum, large amount of oil polluted water will be produced, and the oil polluted water pumping into ocean will destroy ocean environment. To address oil-bearing ballast water, we fabricated a novel type of Fe-C microelectrolysis filler by using magnet powder, coconut shell biochar powder, bentonite, ammonium oxalate, and nickel powder. The COD and oil content removal efficiencies of 100 g/L oily wastewater were approximately 79.82% and 91.68%, respectively, after 100 min treatment at the following conditions: Fe-C mass ratio, 5:1; bentonite content, 20%; calcination temperature, 900 °C; calcination time, 2 h; ammonium oxalate content, 1.5%; and amount of nickel addition, 6.78%. The characteristics of the Fe-C microelectrolysis filler were analyzed. The surface structure of the filler was loose and porous, and its pores were developed. The Brunauer-Emmett-Teller (BET) surface area reached 49.4667 m2 g-1. A microelectrolysis filler is mainly mesoporous and contains large pores. Its average pore size is 2.6942 nm. Meanwhile, the results of our XRD analysis showed that some fillers were metal oxides, and most of them were simple metal substances.