Research Of The Preparation And Capacity Of A New Isobutylene-isoprene Rubber Cryogels Oil Sorbent Material

This paper is about the preparation, characterization and sorption tests ofisobutylene-isoprene rubber （IIR） cryogels. The IIR based cyogels wereprepared at-2^-15℃. Nano SiO₂and graphite were used as modifier and S₂Cl₂was used as cross-linking agent.The pore size of the cryogels prepared at-5and-10℃were large, whichranged from20to50μm when the strut thickness ranged from10to20μm. Themodified cryogels were much water repellent. The sorption velocity of thecryogels for oils with low viscosity was very high. The samples can reachswollen state in only1min, and reach swollen state in7min for oils with highviscosity. After oil uptake, simple squeezing of centrifuging allowed thecryogels to be recycled and reused at least30times.In this study, the oil retention of the cryogels modified with SiO₂wasmuch higher. The oil retention of the samples with SiO₂4w/w%was10%higher than the samples with no SiO₂. While the cryogels modified withgraphite got higher sorption capacity. The max sorption capacity of sampleGC1（-10℃，graphite1w/w%） was21.54g/g for diesel,19.68g/g for crude oiland24.15g/g for lubricating oil, respectively.The cryogel samples also showed excellent sorption capability foraromatic compounds and alkanes. The sorption capacity of the cryogelsmodified with SiO₂reached9.00g/g for benzene,12.80g/g for toluene,12.75g/g for xylene,6.87g/g for hexane,15.90g/g for heptanes and8.21g/g forcyclohexane, respectively. On the other hand, the sorption capacity of thecryogels modified with graphite reached14.13g/g for benzene,17.56g/g fortoluene,21.35g/g for xylene,13.72g/g for hexane and22.78g/g for heptanes,respectively. It was expected that the chain length and polar groups of thepollutants would influence the swelling behavior and sorption. The methylgroups of toluene and xylene have a high affinity for the cryogel networks. Andthe sorption capacity increased with the length of the carbon chain of alkanes.And after a rapid and effective desorption process, taking just3-5hours, thevolume and mass of the cryogels returned to their original values.