Uso da casca de coco verde como adsorbente na remoção de metais tóxicos The use of green coconut shells as absorbents in the toxic metals

• Main Authors: Francisco W. Sousa, Sarah A. Moreira, André G. Oliveira, Rivelino M. Cavalcante, Ronaldo F. Nascimento, Morsyleide F. Rosa
• Format: Article
• Language: English
• Published: Sociedade Brasileira de Química 2007-10-01
• Series: Química Nova
• Subjects: green coconut shells; toxic metals; wastewater
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422007000500019

<abstract language="eng">Green coconut shells were treated with acid, base and hydrogen peroxide solutions for 3, 6, 12 and 24 h for removing toxic metals from synthetic wastewater. The removal of ions by the adsorbent treated with 0.1 mol L-1 NaOH/ 3h was 99.5% for Pb2+ and 97.9% for Cu2+. The removal of Cd2+, Ni2+, Zn2+, using adsorbent treated with 1.0 mol L-1 NaOH/3 h, was 98.5, 90.3 and 95.4%, respectively. Particle size, adsorbent concentration and adsorption kinetics were also studied. An adsorbent size of 60-99 mesh and a concentration of 30-40 g/L for 5 min exposure were satisfactory for maximum uptake of Pb2+, Ni2+, Cd2+, Zn2+ and Cu2+ and can be considered as promising parameters for treatment the aqueous effluents contaminated with toxic metals.