Fe–Al NANO-OXIDE PREPARED BY SOL–GEL METHOD USING PRECURSOR OF HCl DIGESTED LIQUID FRACTION OF LATERITE: ARSENIC ADSORPTION PERFORMANCE

Abstract

Nanoparticle oxide of Fe–Al with surface area 68.9 m2/g and pore volume of 0.10–0.11 mL/g is synthesized using Fe–Al precursor obtained from HCl digested liquid fraction of laterite. Acid digestion of laterite is performed using solid acid ratio of 50 g raw laterite to 200 mL 6 N HCl . The liquid fraction is filtered through Whatman filter of grade 1 and 200 mL filtrate consists mainly of ~ 0.5 mol/L Fe and ~ 0.11 mol/L Al ions. Sol–gel method is used to prepare nano-oxide of Fe–Al . SEM, HRTEM and surface area analyzer are used for textural characterization of the nanoparticles. HRTEM micrograph indicates that sizes of prepared nanoparticles of Fe–Al oxide are in the range of 50 nm to 100 nm. In batch mode operation, 1.5 g/L adsorbent concentration is found to be capable to reduce the arsenic concentration of contaminated groundwater (collected from Dhobdhobi, Mallikpur, 24 Paraganas (s), West Bengal, India) from ~ 440 to ~ 11 μg/L. The Langmuir maximum capacities of As(V) and As(III) from synthetic solution and arsenic (as total) from contaminated groundwater on Fe–Al nano-oxide are obtained as 20.74 mg/g, 6.13 mg/g and 6.8 mg/g, respectively.