Studies on adsorptive removal of lead and chromium compounds using banana pseudo stem and corn cob

Abstract

V newlineABSTRACT newlineThe extensive use of commercial activated carbon as an adsorbent for the purification of newlineindustrial effluent is not economically feasible due its high operational cost. Therefore, newlinethis research has been undertaken to explore the potential of certain agro based residues newlineto produce suitable adsorbent for removal of lead (II) and Chromium (VI) from aqueous newlinesolution. newlineIn this regard, powdered adsorbents were produced from cellulosic precursors namely newlinebanana pseudo stem (BPS) and corn cob (CC) by physio-chemical activation. FTIR, newlineSEM, EDX and PZC characterize the prepared adsorbents to evaluate the newlinephysicochemical properties before and after adsorption of heavy metals such as lead (II) newlineand chromium (VI). Design of experiment (DOE) based on central composite design newline(CCD) was used to study the effect of initial pH, initial metal ion concentration and newlineadsorbent dosage for optimized removal efficiency of lead (II) and chromium (VI). newlineThe results demonstrated that the optimum condition to obtain highest removal newlinepercentage and yield were different depending on the characteristics of the raw materials newlineand the adsorbate under investigation. newlineIn batch study, the experiment conducted and data were found by the amount of newlineadsorption efficiency of lead (II) and chromium (VI) onto unmodified and modified newlinebanana pseudo stem and corn cob. The optimum pH was found 6 for unmodified and newlinemodified BPS and CC on treatment of lead (II) and 4 for unmodified and modified BPS newlineand CC on treatment of chromium (VI) respectively, and maximum adsorbent dosage 1 newline(g/L) obtained for treatment of lead (II) and chromium (VI) onto unmodified and newlinemodified BPS and CC. newlineThe percentage removal of lead (II) and chromium (VI) was studied by selecting these newlinetwo metal ion concentrations from 10 to 50 ppm of interval 10 ppm and varying the newlinecontact time from 20 to 120 minutes with the fixed condition of 1g/L of adsorbent dosage newlineand at constant pH 6 (lead (II)) and pH 4 (chromium (VI)) respectively. It shows that newlinedecrease of the percentage adsorption