• R.Sivakumar
• S.Arivoli
• V.Marimuthu

The presence of hexavalent chromium Cr(VI) ion in wastewater is a potential hazard to aquatic animals and humans. There are various mechanisms proposed, kinetic models used and adsorption isotherms employed for the efficient removal of hexavalent chromium from industrial and municipal wastewaters using biosorbent. Biosorption of heavy metals is a most promising technology involved in the removal of toxic metals from industrial waste streams and natural waters. Metal removal treatment systems using natural materials are cheap because of the low cost of sorbent materials used and may represent a practical replacement to conventional processes. The work aims at adsorption studies of Cr(VI) ion from aqueous solution onto activated nano carbon prepared from Syringodium Isoetifolium Leaves, by acid treatment was tested for its efficiency in removing Cr(VI) ion. The process parameters studied include agitation time, initial chromium ion concentration, adsorbent dose, pH and temperature. The adsorption followed second order reaction equation and the rate is mainly controlled by intra-particle diffusion. The equilibrium adsorption data were correlated with Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Hurkins-Jura, Halsay, Redlich-Peterson, Jovanovich and BET isotherm models. The influence of pH on Cr(VI) ion removal was significant and the adsorption was increased with increase in temperature. A portion of the Cr(VI) ion was recovered from the spent ASI-NC using 0.1M HCl.

Activated Syringodium Isoetifolium Leaves Nanocarbon (ASI-NC), Hexavalent chromium, Biosorption, Thermodynamics, Kinetics, Equilibrium models

"Adsorption Thermodynamics and Isotherm Analyses of Cr(VI) Ion from Aqueous Solution Using Low-Cost Adsorbent", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 6, page no.1044-1060, June-2019, Available :http://www.jetir.org/papers/JETIR1906582.pdf

"Adsorption Thermodynamics and Isotherm Analyses of Cr(VI) Ion from Aqueous Solution Using Low-Cost Adsorbent", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 6, page no. pp1044-1060, June-2019, Available at : http://www.jetir.org/papers/JETIR1906582.pdf