Abstract:
The experimental work has been carried out to study the absorption-desorption properties of the silica aerogels, for
their use in oil spill cleanup application. For these studies, silica aerogel granules were prepared by two step acid–
base catalyzed sol–gel process, involving ambient pressure drying of alcogels, were made use for absorption & desorption
studies of different organic liquids. The optimal molar ratio of precursors tetraethoxysilane (TEOS):Methanol
(MeOH):Oxalic acid:NH4OH:NH4F:trimethylchlorosilane (TMCS) was kept constant at 1:16.5:0.71:0.58:0.60:0.98,
respectively. In all, four alkanes, four aromatic compounds, four alcohols and three oils were used for absorption and
desorption studies of organic liquids. The absorption capacity of aerogel sample was quantified by measuring the mass
of the organic liquid absorbed by unit mass of the aerogel sample. The hydrophobic aerogel granules showed a very
high uptake capacity and high rate of uptake. The desorption of solvents and oils was studied by keeping the liquid absorbed
aerogel granules at various temperatures and weighing them at regular time intervals until all the absorbed
liquid got totally desorbed. The Fourier transform infrared spectroscopy analysis showed that the aerogel structure was
not much affected by the solvent absorption, while the oil absorption led to the shrinkage, resulting in a dense structure
after desorption.
