Treatment of acid rock drainage by clinoptilolite — Adsorptivity and structural stability for different pH environments

Abatement of toluene from polluted air over Mn/Clinoptilolite–CeO2 nanopowder: Impregnation vs. ultrasound assisted synthesis with various Mn-loading

“…In acid treatment of clinoptilolite, it was believed that extra framework cations that could block the pores of clinoptilolite were replaced by H 3 O + and hence dealumination occurs. This phenomenon makes non-crystalline silicate layers and therefore increases the surface area and porosity [33][34][35][36][37].…”

Removal of arsenic from water using Fe-exchanged natural zeolite

“…Under acidic condition the clinoptilolite was stable while the uptake of Fe(III) by clinoptilolite was attributed to cation exchange and was affected by valence charge, the free energy of hydration, and the hydrated size of Fe(III) [29]. The increase of solution pH after Fe(III) sorption during the modification stage could shift the chemical equilibrium of Fe(III) to the formation of Fe(OH) 3 .…”

“…The amount of Fe(III) sorbed was similar to that on a zeolitic tuff collected from Romania, on which Fe(III) sorption capacity was 8 mg/g, corresponding to 140 mmol/kg [24]. The Fe sorption from AMD water on a zeolite collected from Princeton, British Colombia, Canada, was 5-6 g/kg, corresponding to 100 mmol/kg [29].…”

Trace Element Immobilization in Soil Using Amendments

“…Zeolites are reported to have a high selectivity for Cd [83] and Pb [84], but can also effectively sorb Cu, Zn, Tl, Mn, Co and As [47,62,[85][86][87]. However, results of trace element immobilization in contaminated soils following zeolite application are highly variable and were demonstrated to be both positive and negative depending on the soils tested and zeolite types [85,86].…”