Fe-Al NANO-OXIDE PREPARED BY SOL-GEL METHOD USING PRECURSOR OF HC1 DIGESTED LIQUID FRACTION OF LATERITE: ARSENIC ADSORPTION PERFORMANCE

摘要

Nanoparticle oxide of Fe-Al with surface area 68.9 m~2/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 HC1. 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 ～11μg/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.