Formaldehyde crosslinked peanut testa extract was used as an adsorbent to remove Fe²⁺, Ni²⁺, Pb²⁺, Cu²⁺ and Zn²⁺ in wastewater by batch experiments at varying parameter conditions. The efficiencies of the removal processes were found to depend significantly on the pH and temperature of wastewater; initial adsorbate concentration and contact time, less significantly on the amount of adsorbent used but were independent of the stirring speed of the suspension. The removal efficiency of Zn²⁺ increased from 61.2 to 72.1 and to 80.3% at RT, 50 and 60o C respectively. The percentages of Ni²⁺ removed at pH 2, 6 and 8 were: 18.7; 62.7 and 61.9 respectively. The amount of Fe²⁺ removed improved from 21.7 to 78.6 and dropped to 74.2% between the 30^th, 120^th and 150^th minute while 57.4; 46.8 and 33.1 and 57.7; 48.4 and 37.2% of Pb²⁺ were removed at initial concentrations of 10; 20 and 30mg/L respectively. The percentage removal of Fe²⁺ which rose from 65.3 to 71.4 when the adsorbent dose was increased from 2.0 to 4.0g only improved from78.6 to 78.8 when the amount was raised from 8.0 to 10.0g. When the solutions were stirred at 90; 180 and 210 rpm, 56.6; 57.1 and 57.3% of Pb²⁺ were removed. The equilibrium adsorption data agreed with Langmuir isotherm and pseudo-firstorder kinetic models. The study shows that formaldehyde crosslinked peanut testa extract is good for removing Fe²⁺, Ni²⁺, Pb²⁺, Cu²⁺ and Zn²⁺ in wastewater and supports the application of this technique in mitigating the burden of waste disposal. Keyword: Peanut testa extract, heavy metal ions, adsorption, Langmuir isotherm, pseudo-first-order

Biography:
Theresa Uchechukwu is currently a World Bank research fellow at the African Centre of Excellence in Oilfield Chemicals Research, University of Port Harcourt, Nigeria. She has more than 20years work experience in industry laboratories especially in areas of production chemistry, laboratory operations and administration from the Aluminium Smelter Company, Ikot Abasi, Maylux Industries Nigeria Limited, Nigerian Gas Company (NGC) and West African Glass Industry. Her area of interest is in the development of Ion Exchange Resins from Agricultural wastes for the purification of wastewater. Theresa is a highly focused and diligent person, a great listener with excellent organizational skills.