INFLUENCE OF PROCESSING OF NATURAL ZEOLITE UPON METALS REMOVAL CAPACITY

摘要

Natural zeolite deposits contain a variety of accessory minerals in different proportions. Where the proportion of non-exchanging material is high the processing of the deposit has implications for the composition and performance of the resulting product. Material sorted to >50μm after initial crushing shows a lower ion exchange than material sorted to 2-3mm during the initial crash and subsequently ground to >50μm. Adsorption and desorption isotherms were determined for 4 metals and ammonium for both processing routes. The removal of ammonium from solution follows the Langmuir isotherm for both materials with an increase in q(max) from 5.7 to 7,2 mg/g. The Langmuir coefficient showing little alteration between the two cases. The adsorption of metals however is not similarly improved between the two processing routes, with the removal efficiency reducing in all cases, changes in isotherm fitting are also observed.