Search

Abstract: Silica nanoparticles of diameter, 24–75nm and surface area, 875m2/g were synthesized using aero-gel route. Thereafter, nanoparticles were impregnated with reactive chemicals, and used as reactive adsorbent to study the removal of toxic nerve and blister chemical warfare agents and their simulants from solutions. Trichloroisocyanuric acid impregnated silica nanoparticles showed the best performance and indicated physisorption followed by chemisorption/degradation of toxicants. This indicated their suitability as universal decontaminant for nerve and blister agents. This system showed a decrease in t 1/2 from 1210 to 2.8min for the removal of king of chemical warfare agents, i.e., sulphur mustard. Hydrolysis, dehydrohalogenation and oxidation reactions were found to be the route of degradation of toxicants over impregnated silica nanoparticles. [Copyright &y& Elsevier]

Abstract: Alumina nanoparticles in the size range of 2–30nm and surface area 375m2/g were synthesized using aerogel route and then characterized using N2–BET, SEM, TEM, XRD, FTIR and TGA techniques. Thereafter, these were impregnated with reactive chemicals and tested for their potential by conducting studies on kinetics of adsorption of 2-chloroethylethylsulphide (2-CEES) under static conditions. Kinetics was studied using linear driving force and Fickian diffusion model. The kinetics parameters such as equilibration constant, equilibration capacity, diffusional exponent and adsorbate–adsorbent interaction constant were also determined. AP-Al2O3 with 10% impregnation of MoVPA (V3) and NaOH showed the maximum (574mg/g) and minimum (88mg/g) uptake of 2-CEES among impregnated systems respectively. All impregnated systems except NaOH impregnation showed the values of diffusional exponent to be <0.5, indicated the diffusion mechanism to be Fickian, whereas AP-Al2O3 with and without NaOH impregnation showed the diffusional mechanism to be anomalous. Hydrolysis and dehydrohalogenation reactions (identified using GC/MS technique) were found to be the route of degradation of 2-CEES. [Copyright &y& Elsevier]