Abstract

Adsorption equilibrium of arsenic (in both As(III) and As(V) states) onto laterite soil was studied at the temperatures of 298, 308 and 318 K. Batch experiments were conducted to find out the arsenic removal capacity. The effects of process parameters such as contact time, adsorbent dose, adsorbent size, temperature and pH were investigated. Detailed studies on adsorption isotherms (Langmuir, Freundlich and Dubinin-Radushkevich) were conducted. By using the Dubinin-Radushkevich (D-R) isotherm, the energy (E) related with adsorption was calculated and the results showed that the adsorption was mostly physisorption. It was observed by calculating the value of the dimensionless equilibrium parameter (R L ) that the adsorption was favorable. The standard free energy change (ΔG 0 ), enthalpy change (ΔH 0 ) and entropy change (ΔS 0 ) were determined and the calculated values showed that the adsorption process for both As(III) and As(V) was exothermic and spontaneous. Regeneration of the adsorbent was possible using 1M NaOH solution and the regenerated adsorbent could further be used for arsenic removal.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.