INVESTIGATION THE ADSORPTION PROPERTIES OF THE NATURAL ADSORBENTS ZEOLITE AND BENTONITE TOWARDS COPPER IONS

ABSTRACT The possibilities for using Bulgarian natural adsorbents bentonite and zeolite is have been investigated for purification of model solution of Cu 2+ at correlation of liquid to solid phase, v:m=100:1. It has been found out, that the specific surface of the both minerals takes leading part at the adsorption of Cu 2+ from model solutions with concentration higher than 70 mg/dm 3 . The cation adsorption capacity is highest at size of the particles of both adsorbents -0,071+0 mm. The thermodynamics of adsorption has been described with the most appropriate isotherms of uptake of Cu 2+ from different particle sizes adsorbents. It has been reported, that the two natural adsorbents can be used to remove Cu 2+ from model solutions with concentrations not higher than 10-20 mg/dm 3 with one stage of purification at adsorption time 5 min for reaching the Bulgarian standards for drinking waters. Under t these conditions the optimum values of pH for the zeolite are in a wider interval from 4,6 to 8 and for the bentonite 4,6