Magnesium Aluminate Nanoparticles for Chemical Detoxification of Sarin and Soman.

The solutions of Mg(NO3)2, Al(NO3)3, and (NH4)2CO3 were mixed at pH 8 and then heated at 95 °C for 4 h, aged at room temperature for 16 h, and calcined at 650 °C for 4 h to obtain magnesium aluminate nanoparticles. The obtained materials exhibited spinel structure with the particle size being 6 to 26 nm. The nanoparticles demonstrated type IV nitrogen adsorption isotherm, typical of mesoporosity with a surface area of 325 m²/g. They were utilized for studies on chemical detoxification of deadly chemical warfare agents such as sarin and soman. Our results showed that the magnesium aluminate nanoparticles effectively decontaminated more than 99% of sarin and soman within 8-10 min when used at a ratio of 1:50-60% w/w.

Iron phthalocyanine modified mesoporous titania nanoparticles for photocatalytic activity and CO2 capture applications.

An iron(II)phthalocyanine (Fepc) modified mesoporous titania (Fepc-TiO2) nanocatalyst with a specific surface area of 215 m(2) g(-1) has been synthesized by a hydrothermal method. Fepc-TiO2 degrades one of the highly toxic chemical warfare agents, sulfur mustard (SM), photocatalytically under sunlight with an exposure time of as low as 70 min. Furthermore, the mesoporous Fepc-TiO2 also captured 2.1 mmol g(-1) of CO2 at 273 K and 1 atm.

Synthesis of sputter deposited CuO nanoparticles and their use for decontamination of 2-chloroethyl ethyl sulfide (CEES).

We report the synthesis of copper oxide (CuO) nanoparticles by dc magnetron sputtering for adsorptive degradation of 2-chloroethyl ethyl sulfide (CEES), a simulant of well-known chemical warfare agent sulfur mustard (HD). The synthesized CuO nanoparticles were characterized by XRD, TEM, FE-SEM, N2-BET, FT-IR and TGA. The average particle size calculated from XRD pattern was found to be 7 nm for as-deposited and varied up to 86 nm after postannealing. The particle size was also calculated through TEM analysis. The surface area of the particles (∼110-36 m(2)/g) is found to be enhanced significantly in comparison with reported in the literature. Degradation kinetics of CEES was investigated over the CuO nanoparticles and it was found that dc sputtered CuO nanoparticles give superior decontamination properties against CEES. The reactions seemed to be first order with rate constant (k) and half-life (t(1/2)) values in the range of 0.434-0.134 h(-1) and 1.59-5.17 h respectively. The reaction products were characterized by GC-MS and verified through FT-IR. The data reveal the role of hydrolysis reactions in the decontamination of CEES.

Effect of calcinations temperature of CuO nanoparticle on the kinetics of decontamination and decontamination products of sulphur mustard.

Present study investigates the potential of CuO nanoparticles calcined at different temperature for the decontamination of persistent chemical warfare agent sulphur mustard (HD) at room temperature (30 ± 2 °C). Nanoparticles were synthesized by precipitation method and characterized by using SEM, EDAX, XRD, and Raman Spectroscopy. Synthesized nanoparticles were tested as destructive adsorbents for the degradation of HD. Reactions were monitored by GC-FID technique and the reaction products characterized by GC-MS. It was observed that the rate of degradation of HD decreases with the increase in calcination temperature and there is a change in the percentage of product of HD degradation. GC-MS data indicated that the elimination product increases with increase in calcination temperature whereas the hydrolysis product decreases.

Significance of porous structure on degradatin of 2,2' dichloro diethyl sulphide and 2 chloroethyl ethyl sulphide on the surface of vanadium oxide nanostructure.

Degradation of the king of chemical warfare agent, 2,2' dichloro diethyl sulphide (HD), and its simulant 2 chloroethyl ethyl sulphide (CEES) were investigated on the surface of porous vanadium oxide nanotubes at room temperature (30 ± 2°C). Reaction kinetics was monitored by GC-FID technique and the reaction products were characterized by GC-MS. Data indicates that HD degraded faster relative to CEES inside the solid decontaminant compared to the reported liquid phase degradation of CEES and HD. Data explores the role of hydrolysis, elimination and oxidation reactions in the detoxification of HD and CEES and the first order rate constant and t(1/2) were calculated to be 0.026 h(-1), 26.6h for CEES and 0.052 h(-1), 13.24h for HD. In this report faster degradation of HD compared to CEES was explained on the basis of porous structure.

Photocatalytic inactivation of spores of Bacillus anthracis using titania nanomaterials.

Studies on photocatalytic inactivation of spores of Bacillus anthracis have been carried out using nanosized titania materials and UVA light or sun light. Results demonstrated pseudo first order behaviour of spore inactivation kinetics. The value of kinetic rate constant increased from 0.4h(-1) to 1.4h(-1) indicating photocatalysis facilitated by addition of nanosized titania. Nanosized titania exhibited superior inactivation kinetics on par with large sized titania. The value of kinetic rate constant increased from 0.02 h(-1) to 0.26 h(-1) on reduction of size from 1000 nm to 16 nm depicting the enhanced rate of inactivation of Bacillus anthracis Sterne spores on the decrease of particle size.

Decontamination of Yperite using mesoporous mixed metal oxide nanocrystals.

Mixed metal oxide nanocrystals of AP-Al(2)O(3), AP-Al(2)O(3)-Fe(2)O(3), AP-Al(2)O(3)-V(2)O(5) and AP-Al(2)O(3)-CuO have been prepared by aerogel process. XRD data of prepared materials revealed the formation of nanocrystals with a size range of 3-15 nm diameters. N(2) BET investigations on these materials revealed larger values of surface area ranging from 350 to 540 m(2)/g. Reactivity of these nanocrystalline materials against Yperite was examined by gas chromatography, gas chromatography-mass spectrometry and infrared spectroscopy techniques. AP-Al(2)O(3)-Fe(2)O(3), AP-Al(2)O(3)-V(2)O(5) and AP-Al(2)O(3)-CuO nanocrystals exhibited superior decontamination properties against Yperite than AP-Al(2)O(3). The reactions exhibited pseudo first order behaviour. 100% of Yperite was found to be decontaminated on Al(2)O(3)-Fe(2)O(3), Al(2)O(3)-V(2)O(5) and Al(2)O(3)-CuO where only 75% of the same was found to be decontaminated on AP-Al(2)O(3) within 40 h.

Modified titania nanotubes for decontamination of sulphur mustard.

Modified titania nanotubes have been studied as powder decontaminants against sulphur mustard (HD), a deadliest chemical warfare agent. Decontamination reactions were carried out at room temperature (30+/-2 degrees C) and monitored by gas chromatography and gas chromatography mass spectrometry techniques. Reactions displayed first order kinetics. HD underwent accelerated hydrolysis on Ag(+)-titania nanotubes when compared to Cu(2+), Ni(2+), Co(2+), Mn(2+) and Ru(3+)-titania nanotubes depicting catalysis. Thiodiglycol, 1,4-oxathiane were observed to be major products formed except on Ru(3+)-titania nanotubes. Sulphur mustard sulphoxide formed on Ru(3+)-titania nanotubes indicating oxidative decontamination of HD.

Nanocrystalline zinc oxide for the decontamination of sarin.

Nanocrystalline zinc oxide materials were prepared by sol-gel method and were characterized by X-ray diffraction, scanning electron microscopy, thermogravimetry, nitrogen adsorption and infrared spectroscopy techniques. The data confirmed the formation of zinc oxide materials of zincite phase with an average crystallite size of approximately 55 nm. Obtained material was tested as destructive adsorbent for the decontamination of sarin and the reaction was followed by GC-NPD and GC-MS techniques. The reaction products were characterized by GC-MS and the data explored the role of hydrolysis reaction in the detoxification of sarin. Sarin was hydrolyzed to form surface bound non-toxic phosphonate on the surface of nano-zinc oxide. The data also revealed the values of rate constant and half-life to be 4.12h(-1) and 0.16 h in the initial stages of the reaction and 0.361 h(-1) and 1.9h at the final stages of the reaction for the decontamination reaction on nanocrystalline ZnO.

Reactions of sulphur mustard and sarin on V 1.02 O 2.98 nanotubes.

Reactions of sulphur mustard and sarin were studied on the surface of V(1.02)O(2.98) nanotubes by gas chromatography and gas chromatography-mass spectrometry techniques. The V(1.02)O(2.98) nanotube samples were made by using hydrothermal method and characterized by scanning electron microscopy, nitrogen adsorption, X-ray diffractometry and thermogravimetry. Later, they were exposed to sulphur mustard and sarin separately at ambient temperature (30+/-2 degrees C). The data explored the formation of sulphoxide of sulphur mustard, thiodiglycol for sulphur mustard and isopropyl methyl phosphonic acid for sarin on V(1.02)O(2.98) nanotubes illustrating the role of oxidation and hydrolysis reactions in the decontamination.

Photocatalytic inactivation of Bacillus anthracis by titania nanomaterials.

Photocatalytic inactivation of Bacillus anthracis was studied by using titania nanomaterials and UVA light. Experimental data clearly indicated that, time of exposure, quantity of catalyst, intensity of light, particle size and Sunlight affected the inactivation. It also demonstrated the pseudo-first order behavior of inactivation kinetics and pointed out the enhanced rate of inactivation in the presence of nano-titania existing as a mixture of anatase and rutile phases. The values of rate constant were found to increase when the quantity of catalyst and intensity of UVA light were increased. Nanosized titania exhibited better inactivation properties than the bulk sized titania materials. Sunlight in the presence of nano-titania (mixture of anatase and rutile phases) displayed better photocatalytic bactericidal activity of B. anthracis than sole treatment of Sunlight.

Detoxification reactions of sulphur mustard on the surface of zinc oxide nanosized rods.

Detoxification reactions of sulphur mustard, a deadliest chemical warfare agent were studied on the surface of zinc oxide nanorods at room temperature (32+/-2 degrees C) and the data was compared with that of the bulk ZnO. Prior to the reaction, the nanorods of zinc oxide were synthesized by the hydrothermal method and subsequently characterized by XRD, SEM, TG, N(2) BET, FT-IR. The data revealed the formation of nanorods with diameter ranging from 100 nm to 500 nm with length in microns. Obtained nanomaterial along with bulk ZnO were tested as reactive sorbent for the detoxification of sulphur mustard. Reaction was monitored by GC-FID technique and the reaction products were characterized by GC-MS. Data explores the role of hydrolysis and elimination reactions in the detoxification of sulphur mustard and it also reveals that zinc oxide nanorods and bulk ZnO show the half lives of 8.48 h, 24.75 h in the first 12h and 122.47 h, 177.29 h from 12h to 48 h of the reaction.

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).

Lamellar nanocomposites based on exfoliated SbP2O8- nanosheets and ionic polyacetylenes.

Novel lamellar nanocomposites composed of exfoliated SbP2O8- nanosheets and poly(N-methyl-2-ethynyl pyridinium iodide) (PNMe) or poly(N-octadecyl-2-ethynyl pyridinium bromide) (PNO) have been synthesized by exfoliation and re-stacking method. The XRD data of the nanocomposites SbP2O8-:PNMe and PNO:SbP2O8- indicate the formation of nanostructures containing SbP2O8- nanosheets and PNMe or PNO with interlayer expansions of 2.22 and 4.2 nm along the stacking direction of SbP2O8- nanosheets. Formation of these nanocomposites is further supported by the results obtained by FT-IR spectroscopy, scanning transmission electron microscopy and thermogravimetry. The values of electrical conductivity of the polymers and nanocomposites have also been measured.

Evaluation of different granulated active carbons for removal of Microcystin-LR from contaminated water.

Most frequently encountered freshwater cyanobacterial toxin is Microcystin-LR (MC-LR). Microcystins released from cells into water have been responsible for the death of humans, domestic and wild animals. Removal of microcystin by active carbon has been one of the best methods available so far. This study evaluates three grades of active carbon namely 40, 60 and 80 CTC for their removal efficiency of MC-LR from contaminated water. Kinetics of toxin removal was studied in time course experiments. Protection in mouse model was studied for the samples after the adsorption. Toxin quantitation was done by HPLC method. The MC-LR concentration after 24 hr treatment with 40, 60 and 80 CTC carbons were 4.8, 3.3 and 1.3 microg/ml respectively from an initial concentration of 5.2 microg/ml. Protection in mouse bioassay was seen after 48, 24 and 2 hr of adsorption time respectively for 40, 60 and 80 CTC carbons. 80 CTC carbon was found to be most efficient in removing MC-LR from contaminated water.

Impregnated carbon for degradation of diethyl sulphide.

Activated carbon of surface area 1100 m2/g was impregnated with 5 wt.% ruthenium chloride by using its aqueous solution. Obtained carbon was exposed to the vapors of diethyl sulphide at room temperature (30+/-1 degrees C). Thereafter, the reaction products were extracted in dichloromethane and analyzed using gas chromatography and mass spectrometry. The data revealed that, the impregnated carbon reacted with diethyl sulphide producing the diethyl sulphone. In addition to the above reaction product, residual reactant was also observed. Reaction mechanisms have also been proposed for these interesting surface reactions.

Nanocomposite based on poly(N-octadecyl-2-ethynylpyridinium bromide) and Mg(0.04)Nb(1.66)O5 nanosheets.

A novel nanocomposite based on poly(N-octadecyl-2-ethynylpyridinium bromide) (PNOEtPyBr) and Mg(0.04)Nb(1.66)O5 nanosheets is synthesized by the method of exfoliation-reflocculation. The XRD data of the nanocomposite indicates the formation of Mg(0.04)Nb(1.66)O5 nanosheets/PNOEtPyBr nanostructure with an interlayer expansion of 4.6 nm along a direction perpendicular to the Mg(0.04)Nb(1.66)O5 nanosheets. Formation of this nanocomposite is further supported by the results obtained by FT-IR spectroscopy and thermogravimetry. This nanocomposite exhibits interesting dielectric properties with a dielectric constant of 18.7 F/m at 1000 Hz and 25 degrees C, which are also compared to the properties of HMg(0.34)Nb(1.66)O5 and PNOEtPyBr.

Kinetics of degradation of sulphur mustard on impregnated carbons.

Kinetics of degradation of sulphur mustard (HD) on the surface of NaOH/CrO3/C, NaOH/CrO3/EDA/C and RuCl3/C systems has been examined by using gas chromatography technique by extracting and analyzing the residual HD periodically. The carbons were prepared by impregnating activated carbon with 4% sodium hydroxide plus 3% Cr(VI) as CrO3 with and without 5% ethylene diamine (EDA) and 5% ruthenium chloride by using their aqueous solutions. Obtained carbons were characterized for surface area analysis by BET conventional method. Kinetic plots reveal that the observed reactions are fast at the initial stages, slow at the later stages and progress to a steady state indicating the first order behavior. Effect of moisture on kinetic rate is also observed. In the case of NaOH/CrO3/C system the rate constant is decreased from 13.36 to 5.53 x 10(-2) h(-1) and half life is increased from 5.2 to 12.54 h while moisture content is increased from 1.9% to 11.2%. Whereas, the rate constant of HD degradation reaction is decreased from 10.4 to 4.14 x 10(-2) h(-1) and half life is increased from 6.7 to 16.72 h while moisture content is increased from 2.1% to 10.8% on NaOH/CrO3/EDA/C. Reaction on RuCl3/C system also behaves in the similar manner. Extracted reaction products were characterized by GC/MS and it is found that on NaOH/CrO3/C, HD degrades to hemisulphur mustard, thiodiglycol and 1,4-oxathiane. Whereas, on NaOH/CrO3/EDA/C, HD is degraded to 1,4-thiazane and it is degraded to divinyl sulphone on RuCl3/C. All these investigations reveal that above mentioned carbons can be used in nuclear, biological and chemical (NBC) filtration systems for protection against sulphur mustard.