Practical Oil Spill Recovery by a Combination of Polyolefin Absorbent and Mechanical Skimmer

The objective of this research is to develop a practical and efficient oil recovery method that can be applied in large-scale crude oil spills in open water. The method is centered on a newly developed polyolefin oil superabsorbent, called i-Petrogel, in conjunction with existing mechanical (skimmer) recovery method. The i-Petrogel absorbent can be produced in large scale (>90 kg in our laboratory) by mixing two polyolefin polymers, including a semicrystalline linear low-density polyethylene (LLDPE) thermoplastic and a thermally cross-linkable poly(1-decene-co-divinylbenzene) (D-DVB) elastomer, to form an interpenetrated network structure with porous morphology. In two practical tests, i-Petrogel with a specific composition (LLDPE/D-DVB:1/1 weight ratio) shows selective absorption of Alaska North Slope crude oil on open water surface with fast kinetics and high absorption capacity of more than 40 times that of the polymer weight. In fact, i-Petrogel effectively stops the crude oil weathering process (evaporation, emulsification, and spreading) in open water. Furthermore, on the basis of our rheological findings on the resulting gel adducts, we propose that one can effectively recover these gels by a drum skimmer in both warm and cold conditions. The recovered oil/i-Petrogel adducts (hydrocarbons) contain almost no water, which can be refined as the original crude oil using regular refining processes (instead of chemical wastes). Overall, i-Petrogel technology potentially provides a comprehensive solution for combating crude oil spills in open waters, with dramatic reduction of environmental impact.