Recycle of oil waste via hydrophobic sponge prepared from toner waste

In this paper a hydrophobic sponge was prepared by solvent free coating of thermosetting toner from a laser printer via simple heating. The sponge was used for oil-water mixture and emulsion separation. The sponge had good separation performance for the oil-water mixture. In dynamic oil recovery study, the sponge had a flux up to thousands L/(m²·h) for kerosene and n-hexane. For the water-in-petroleum emulsion with 60% water content, the final water content could be brought down to 1.7-5.0% after 2 cycles of operation. While for the water-in-kerosene emulsion with low water content of 10%, the recovered oil had water content below 1.0%. The study revealed a potential industrial utilization of toner waste, which was beneficial to the emission reduction, and a facile way for fast separation of light oil from water, which was beneficial to the oil waste treatment.