Continuous preparation of polyHIPE monoliths from ionomer-stabilized high internal phase emulsions (HIPEs) for efficient recovery of spilled oils

Abstract

We present a facile and continuous approach to prepare polyHIPE monoliths for efficient reclamation of spilled oils. The polyHIPE monoliths were produced from a light induced polymerization of an ionomer, namely sulfonated polystyrene stabilized high internal phase emulsions (SPS-HIPEs). The SPS-HIPEs consisted of seawater as the dispersed aqueous phase and inexpensive monomers such as butyl acrylate and tetraethyl orthosilicate (TEOS) as the continuous phase. Sulfonated polystyrene was from used foams, realizing a sustainable transformation of waste polystyrene. PolyHIPE monoliths from SPS-HIPEs (SPS-polyHIPEs) reached a high gel fraction of 93% with exposure to UV light for only 5min, providing a possibility to produce them continuously. SPS-polyHIPEs are much greener in comparison to those from surfactant- or particles-stabilized HIPEs, and no purification is required prior to use. SPS-polyHIPE monoliths exhibit interconnected macro-porous structures, and the sizes of pores as well as pore throats can be controlled simply by the volume fraction of the dispersed phase. These monoliths are hydrophobic with a water contact angle over 140°. Excellent performances have been verified for oil spill reclamation, including high absorption capacity to a series of organic solvents or oils, high absorption rate of reaching saturated absorption in 3–5min, a high recovery rate over 85% and a high reusability over 20 times. A continuous process has been illustrated using SPS-polyHIPEs as absorbents for oil spill recovery.