Modified mesoporous silicates for the adsorption and decomposition of toxic gases

New adsorbents based on MCM-41 have been developed for the adsorption and decomposition of HCN and CNCl. Adsorption of CNCl is provided by diaminoalkylsilane tethers bound to the surface. Reactivity towards HCN is provided by Cu2+ ions complexed by the diamines. Overall reactivity towards the two gases depends on the balance between free amine and Cu2+ concentrations. The performance of these adsorbents is superior to that of carbon-based adsorbents in which alkylamine and copper(II) salt are physisorbed on the carbon surface.