Pomelo peel modified with acetic anhydride and styrene as new sorbents for removal of oil pollution.

Pomelo peel (PP), as one of the well-known agricultural wastes, is cost-effective and environmentally friendly. Based on PP, two new kinds of oil sorbents were prepared by using acetic anhydride and styrene. The structures of raw pomelo peel (RP), acetic anhydride-treated pomelo peel (AP) and styrene-treated pomelo peel (SP) were characterized by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM), contact-angle (CA) measurements. The optimum reaction conditions for preparation of AP and SP were also investigated. The resulting products exhibited better oil sorption capacity than that of RP for diesel and lubricating oil, also SP had better oil sorption capacity than AP, while the oil sorption capacities of SP for diesel and lubricating oil reached 18.91 and 26.36 g/g, respectively. Adsorption kinetics was well described by the pseudo-second-order model. The results indicated that AP and SP, especially SP could be used as the substitute for non-biodegradable oil sorption materials.

Graphite/isobutylene-isoprene rubber highly porous cryogels as new sorbents for oil spills and organic liquids.

The preparation, by a freeze-thaw method, of new graphite/isobutylene-isoprene rubber (IIR) sorbents for oil and organic liquid is described. Graphite was expected to improve the adsorption properties. The cryogels were prepared by solution crosslinking IIR rubber in the presence of graphite in benzene at various temperatures, using sulfur monochloride as the crosslinker, and characterized by SEM and contact angle measurements. The dried cryogels, with interconnected macropores were sponge-like soft materials, with excellent buoyancy and hydrophobicity. They also showed excellent sorption characteristics, with the best sample exhibiting maximum sorption capacities of 17.8 g g(-1) for crude oil, 21.6 g g(-1) for diesel oil, and 23.4 g g(-1) for lubricating oil, respectively. The samples also showed excellent sorption capability for organic liquids, absorbing up to around twenty times their own mass. After rapid and effective desorption, taking just 3-5 h, the cryogels were recovered. They could also be reused more than 30 times by simply centrifuging to remove the sorbed liquid. These characteristics mean that the cryogels prepared in this study are promising materials for removal of large-scale oil or toxic organic spills.