Evaluation of Croatian clinoptilolite- and montmorillonite-rich tuffs for ammonium removal
Year: 2002
Type: article
Abstract: In this study, the ability of a Croatian clinoptilolite- and montmo-rillonite-rich tuffs to take up ammonium from aqueous solutions was investigated. Montmorillonite tuff was converted into the Na+ and H+ form by treatment with Na2CO3 (w = 3–5%) and the solu-tion of H2SO4 (w = 15%). The properties of clay modified in this way were investigated as well. The results show that the clinoptilolite tuff efficiency for ammonium removal is far superior (by 45–50%) to the removal efficiency of montmorillonite tuff. Treatment of mont-morillonite tuff with Na2CO3 resulted in a slight improvement of its ammonium exchange efficiency. Acid modification of montmoril-lonite tuff causes a considerable decrease of ammonium exchange. Maximum loadings in ammonium exchange in clinoptilolite tuff, montmorillonite tuff, alkaline modified montmorillonite tuff, and acid modified montmorillonite tuff, as calculated by the Langmuir equa-tion, are 1.20, 0.54, 0.64, and 0.21 mmol g–1 NH4+, respectively. Key words: clinoptilolite-rich tuff, montmorillonite-rich tuff, alka-line modification, acid modification, ammonium removal.
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2526808068