Impregnated silica nanoparticles for the reactive removal of sulphur mustard from solutions

Abstract

High surface area (887.3 m 2/g) silica nanoparticles were synthesized using aerogel route and thereafter, characterized by N 2-Brunauer–Emmet–Teller (BET), SEM and TEM techniques. The data indicated the formation of nanoparticles of silica in the size range of 24–75 nm with mesoporous characteristics. Later, these were impregnated with reactive chemicals such as N-chloro compounds, oxaziridines, polyoxometalates, etc., which have already been proven to be effective against sulphur mustard (HD). Thus, developed novel mesoporous reactive sorbents were tested for their self-decontaminating feature by conducting studies on kinetics of adsorptive removal of HD from solution. Trichloroisocyanuric acid impregnated silica nanoparticles (10%, w/w)-based system was found to be the best with least half-life value ( t 1/2 = 2.8 min) among prepared systems to remove and detoxify HD into nontoxic degradation products. Hydrolysis, dehydrohalogenation and oxidation reactions were found to be the route of degradation of HD over prepared sorbents. The study also inferred that 10% loading of impregnants over high surface area and low density silica nanoparticles enhances the rate of reaction kinetics and seems to be useful in the field of heterogeneous reaction kinetics.