Sorption behavior of tritiated water on Armenian natural zeolites

The use of columns of the zeolite clinoptilolite in the remediation of aqueous nuclear waste streams

“…Clinoptilolite is one of 20 naturally occurring zeolites that have been used to extract aqueous radionuclides, and although Cs + and Sr 2+ are the most commonly extracted species, U, Th, Ra, Am, 3 H and Co are also extracted [ 5 , 9 ]. It has been suggested that clinoptilolite could form a component of permeable reactive barriers for the remediation of Cs + and Sr 2+ contaminated sites [ 10 , 11 ].…”

Effects of γ-irradiation on the Cu2+ sorption behaviour of NaOH-modified Philippine natural zeolites

“…Lower water content in the channels of zeolites increases free space, which facilitates diffusion of incoming cations in the exchangeable sites (Moraetis et al , 2007). This means more room for incoming Cu 2+ ions (Keheyan et al , 2005), partly related to the slight increase in the HTO sorption capacity of Armenian zeolite due to the dehydration/dehydroxylation of the zeolite surface.…”

“…(Moraetis, et al, 2007) This means more room for incoming Cu 2+ ions. (Keheyan, et al, 2005) somewhat associate the slight increase in the HTO sorption capacity of Armenian zeolite to the dehydration/ dihydroxylation of the zeolite surface.…”

“…This confirms the reported enhancement of the Cu 2+ sorption capacity of γ-irradiated NaOH-modified zeolites in our previous study . (Keheyan, et al, 2005) reported that γ-irradiation at 200 and 700 kGy slightly increases the sorption capacity of raw Armenian clinoptilolite-rich natural zeolites on tritiated water (HTO). However, no direct dependence between the sorption and irradiation dose was observed.…”

“…Best-fit lines of the linearized adsorption kinetic data according to (a) Lagergren's pseudo-first-order kinetic model, (b) the pseudo-second-order kinetic model and (c) the intra-particle kinetic model. Keheyan et al (2005) reported that γ-irradiation at 200 and 700 kGy slightly increased the sorption capacity of raw Armenian clinoptilolite-rich natural zeolites for tritiated water (HTO). However, no direct dependence between the sorption and irradiation dose was observed.…”