The adsorptive removal of arsenic and
fluoride in single as well
as binary system is studied with the help of acid-base treated
laterite as adsorbent. For single component system, the optimal
conditions for maximum removal of arsenic and
fluoride are found
at pH 5, adsorbent dose 20 g L1 and contact time 300 min. Both
Langmuir and Freundlich isotherms
fitted the equilibrium data
well; however Langmuir isotherm described the adsorption
process better for single component system. The maximum
Langmuir adsorption capacities are found to be 769 mg g1 and
526 mg g1 for arsenic and
fluoride respectively for single
component system. Both the anions followed pseudo second
order kinetics for adsorption. In the binary system, extended
Freundlich model
fitted best for the experimental data for both
arsenic and
fluoride. The leaching test (WET) also revealed
negligible concentration of arsenic and
fluoride in the leachate
which implicates the environmental sustainability of the adsor-
bent.