Coal and <i>Zea mays</i> cob waste as adsorbents for removal of metallic ions from wastewater

Abstract

The efficiency of coal (CO) and Zea mays (ZM) cob adsorbents for the removal of metallic ions from wastewater is reported. The adsorbents were used in both their granular (GCO and GZM) and powdered (PCO and PZM) forms respectively. Chromium, nickel, iron and cadmium were used as
model ions. Efficiency of the method relied on the use of Shimadzu AA650 double beam atomic absorption/flame spectrophotometer. Effects of varying adsorbent dose, adsorbate loading concentration, pH and adsorbent surface area on the percentage removal of the adsorbates were
studied. Results revealed that coal relatively have higher affinity for the tested ions compared to zea mays cob. The order of removal on the two adsorbents are nearly similar with little variations for Ni and Cd. Thermodynamic analyses at 303, 313, 323 and 333K and at optimum adsorbent weight and 60mgL-1 initial adsorbate loading concentration indicates a spontaneous and feasible process.

Keywords: Adsorbate, Adsorbent, Coal, % Removal, Wastewater, Zea mays cob.