Post-Consumer Polyurethane Foams Hydrophobization Through Surface Modifications for Oil Spill Sorption

To increase oil sorption, polyurethane foams were modified with MoS₂, ZnO grafting and/or hexadecanoic acid coating. The foams were characterized by Scanning Electron Microscopy + Energy Dispersive X-ray Spectroscopy and Contact Angle techniques. Three sorption tests were performed. In tests with 100% water, the ZnO-PC modification showed a reduction of 35.7% in the seawater sorption when compared to Un-PC. In tests with 100% oil, there was a 29-fold increase in sorption (more than 2803%) of S46 lubricant oil when Un-PC performance was compared with ZnO-PC. In tests on the multicomponent systems, the lowest seawater sorption was 0.01 ± 0.00 g.g^-1 (HA-PC), 0.08 ± 0.01 g.g^-1 (Un-PC), and 1.39 ± 0.02 g.g^-1 (Un-PC) for 20W40 engine oil, S46 lubricating oil, and diesel, respectively. The highest oil sorption in the systems was 41.34 ± 1.02 g.g^-1 (HA-PC), 32.81 ± 0.31 g.g^-1 (MoS₂-PC), and 14.78 ± 0.27 g.g^-1 (ZnO-PC) for diesel, S46 lubricating oil, and 20W40 engine oil, respectively. The reuse tests indicated that even after 10 cycles, the ZnO-PC foam kept its sorption capacity unchanged. Post-consumer foams proved to be effective in the sorption of different oils spilled into seawater, especially those grafted with ZnO rods or impregnated with MoS₂.

Keywords:
Oil pollution; Oil spills; Polyurethane foams; Reduce; reuse; recycle