Adsorption and Reaction of 2-Chloroethylethyl Sulfide with Al₂O₃ Surfaces

Abstract

The reaction of 2-chloroethylethyl sulfide (CEES) with a high-area Al2O3 surface was investigated. Two different reactive sites were created by thermally pretreating the Al2O3 powder: isolated hydroxyl sites and Lewis acid−base pair sites. The reaction of CEES with the isolated hydroxyl groups at 303 and 473 K produced a surface-bound species, which is characterized by a carbon−oxygen stretching mode near 1100 cm-1. This assignment was confirmed by isotopic substitution of 18O into the isolated hydroxyl groups prior to reaction with CEES. The other reaction product detected at 473 K was HCl. For a more highly dehydroxylated Al2O3 surface, the reaction of CEES with the Lewis acid−base pairs produced a surface−bound species also exhibiting a carbon−oxygen stretching mode near 1100 cm-1. This species is postulated to form at O2- Lewis base sites as Al3+−Cl- bonds form on adjacent Lewis acid sites. The adsorption of pyridine onto the Lewis acid sites prior to CEES exposure effectively closes this reaction pathway. A maximum Al2O3 reactivity was achieved by pretreatment of the Al2O3 in the temperature range 673−773 K, judging by the integrated absorbance intensity of the product1100 cm-1 mode. This reactivity maximum is expected if both the isolated hydroxyl groups and Lewis acid−base pairs are involved in the reaction.

A facile ceria–zirconia binary oxide used for degradation of 2-chloroethyl ethyl sulfide

“…Figure 5 shows the ATR-FTIR spectra recorded after 5-min, 1-hour and 4-hour adsorption, respectively. According to previous literatures [4,9,13], the triplet band between 2850 and 2950 cm -1 corresponds to C-H stretching modes. The bands at 1442 and 1372 cm -1 are assigned to CH 3 deformation modes, the bands at 1260, 1215, 700 cm -1 are assigned to SC-H 2 scissor mode, ClC-H 2 scissor mode, and Cl-C vibrational modes, respectively.…”

“…For instance, the surface hydroxyl groups connecting to an edge and a corner, i.e., isolate hydroxyl groups, Electronic supplementary material The online version of this article (doi:10.1007/s10853-015-9159-x) contains supplementary material, which is available to authorized users. exhibit higher hydrolysis or nucleophilic substitution reactivity due to their basic characteristic compared to associated hydroxyl groups on flat planes [13,14].…”

Decontamination of Chemical Warfare Agents

“…However, hydrogen carbonate activator is efficient at generating peroxy anion 31 (OOH) for VX and GD perhydrolysis 75 . The reaction mechanism is similar to as given in Figs 8 to 11. 7.27 Nanosized Metal Oxides as CWA Decontaminants Recently, nanosized particles of MgO, Al 2 O 3 and CaO have been found to be the potential reactive sorbent materials owing to their high surface area, strong adsorbability, potential reactivity towards chemical warfare agents, and these remove the agent rapidly from the contaminated surfaces and degrade them in situ and render the hazardous agents non-toxic [32][33][34][35][36][37][38] . In addition, titania nanotubes, manganese oxide nanotubes were also found to be having promising CWA decontamination properties [76][77][78][79][80] .…”

“…Besides this, nanosized particles of MgO, Al 2 O 3 and CaO are promising reactive sorbent materials that have been used as advanced decontaminant materials. Owing to their high surface area, strong adsorbability, potential reactivity towards chemical warfare agents, these nanosized particles remove the agent rapidly from the contaminated surfaces and degrade it in-situ and render the agent non-toxic [32][33][34][35][36][37][38] .…”

Tungsten oxide: a catalyst worth studying for the abatement and decontamination of chemical warfare agents

“…The catalytic performance of inorganic oxides in the decontamination of hazardous chemicals is, to a large extent, related to their form, size and shape. When they are bulk aggregates or macroscopic powders, they are able to remove the hazardous contaminant quite efficiently by physical adsorption, but, then, they can scarcely degrade and catalytically convert it into nontoxic by-products (Mawhinney, Rossin, Gerhart, & Yates, 1999;Prasad, Ramacharyulu, Kumar, Ganesan, & Singh, 2012). On the other hand, when the inorganic oxides are dispersed at nanosized level, the large presence of defective and highly reactive sites at the surface of the solid gives rise to acid-base and/or redox properties and hence to enhanced hydrolytic and/or degradation capabilities (Guidotti, Evangelisti, Rossodivita, & Ranghieri, 2014).…”