Adsorption isotherms of removing copper from aqueous solutions by low cost adsorbent-lignite

Abstract

Serbian lignite from ’’Kolubara’’ deposit was used as a low cost adsorbent for removal of copper ions (Cu2+) from aqueous solutions. Lignite was subjected to the elementary and technical analysis as well as BET and FTIR analysis to provide complete characterization. Basic comparison between lignite and activated carbon was also done. Adsorption efficiency was studied as function of initial metal concentration and amount of adsorbent. Three different amounts of lignite were used (30, 45, and 60 g). Initial solutions with three different concentrations of copper (50, 200, and 330 mg/l) were prepared. Results proved that investigated lignite is very efficient sorbent material, especially in case of low copper concentration where the usual methods are either economically unrewarding or technically complicated. The effect of adsorbent amount on adsorption kinetics is visible but not crucial.