Simple time weighted average level air-monitoring method for sulfur mustard in work places

Sulphur mustard vapor breakthrough behaviour on reactive carbon systems

Breakthrough behaviour of sulphur mustard, the deadliest of persistent chemical warfare agents, on carbon systems such as NaOH/CrO(3)/C, NaOH/CrO(3)/EDA/C and RuCl(3)/C has been studied and the data were compared with that of active carbon. Effects of bed lengths of carbons on breakthrough time have also been correlated. Thereafter, the effects of flow rate of air-sulphur mustard mixture, concentration and temperature on the kinetic parameters such as rate constant (k(v)) and kinetic saturation capacity (W(e)) were analyzed and interpreted by means of modified Wheeler equation. Rate constant was found to be increasing while W(e) was found to be invariable with the increase in air flow rate. Both k(v) and W(e) decreased with the increase of temperature, however, no significant effect on W(e) and k(v) was observed due to concentration change (0.3-0.6 mg/l). The values of kinetic saturation capacity were used to predict the service lives/breakthrough times of carbon beds (when used in filtration systems).

Breakthrough behavior of diethyl sulphide vapor on active carbon systems

Breakthrough behavior of diethyl sulphide vapors on carbon systems such as active carbon, NaOH/CrO3/C, NaOH/CrO3/EDA/C and RuCl3/C has been studied by using modified Wheeler equation and the same was used to calculate the pseudo-first-order rate constant (kv) and kinetic saturation of capacity (W(e)) values. Effects of various parameters such as bed height, air flow rate, concentration and temperature on the above parameters have also been studied. Rate constant was found to be increasing with air flow rate, while W(e) was found to be invariable. Both kv and W(e) decreased with the increase in temperature, however, no significant effect on W(e) and kv was observed due to concentration change. The values of kinetic saturation capacity were used to predict the service lives/breakthrough times of carbon beds (when used in filtration systems).

Breakthrough behavior of sulphur mustard vapor on whetlerite carbon

Sulphur mustard vapor breakthrough behavior on whetlerite carbon has been studied by using modified Wheeler equation. The values of pseudo-first-order rate constant (k(v)) and kinetic saturation capacity (W(e)) were calculated and the effects of various parameters such as bed height, air flow rate, concentration and temperature on the above parameters have also been studied. Rate constant is found to be increasing with air flow rate, while W(e) is found to be invariable. Both k(v) and W(e) decrease with the increase of temperature, however, no significant effect on W(e) and k(v) is observed due to concentration change. The values of kinetic saturation capacity are used to predict the service lives/breakthrough times of carbon beds (when used in filtration systems).

Preparation and application of the sol–gel-derived acrylate/silicone co-polymer coatings for headspace solid-phase microextraction of 2-chloroethyl ethyl sulfide in soil

Three types of novel acrylate/silicone co-polymer coatings, including co-poly(methyl acrylate/hydroxy-terminated silicone oil) (MA/OH-TSO), co-poly(methyl methacrylate/OH-TSO) (MMA/OH-TSO) and co-poly(butyl methacrylate/OH-TSO) (BMA/OH-TSO), were prepared for the first time by sol-gel method and cross-linking technology and subsequently applied to headspace solid-phase microextraction (HS-SPME) of 2-chloroethyl ethyl sulfide (CEES), a surrogate of mustard, in soil. The underlying mechanisms of the coating process were discussed and confirmed by IR spectra. The selectivity of the three types of sol-gel-derived acrylate/silicone coated fibers was studied, and the BMA/OH-TSO coated fibers exhibited the highest extraction ability to CEES. The concentration of BMA and OH-TSO in sol solution was optimized, and the BMA/OH-TSO (3:1)-coated fibers possessed the highest extraction efficiency. Compared with commercially available polyacrylate (PA) fiber, the sol-gel-derived BMA/OH-TSO (3:1) fibers showed much higher extraction efficiency to CEES. Therefore, the BMA/OH-TSO (3:1)-coated fibers were chosen for the analysis of CEES in soil matrix. The reproducibility of coating preparation was satisfactory, with the RSD 2.39% within batch and 3.52% between batches, respectively. The coatings proved to be quite stable at high temperature (to 350 degrees C) and in different solvents (organic or inorganic), thus their lifetimes (to 150 times) are longer than conventional fibers. Extraction parameters, such as the volume of water added to the soil, extraction temperature and time, and the ionic strength were optimized. The linearity was from 0.1 to 10 microg/g, the limit of detection (LOD) was 2.7 ng/g, and the RSD was 2.19%. The recovery of CEES was 88.06% in agriculture soil, 92.61% in red clay, and 101.95% in sandy soil, respectively.