Author: Rasoul Hoseini Seyed Alidokht Leila Oustan Shahin Aliasgharzad Naser Najafi Norsatollah
Publisher: Taylor & Francis Ltd
E-ISSN: 1549-7887|24|5|554-572
ISSN: 1532-0383
Source: Soil and Sediment Contamination: An International Journal, Vol.24, Iss.5, 2015-07, pp. : 554-572
Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.
Abstract
In this research, kinetics of Cr(VI) reduction by iron filings was investigated through a batch study in seven different soils. Chromate reduction experiments were carried out for initial Cr(VI) concentrations ranging from 20 to 100 mgkg−1 and iron filings dosage of 0 to 5% w/w. The experimental data were analyzed using various kinetic models including zero-order, pseudo first-order, power function, Elovich, and diffusion parabolic. Results showed that the Cr(VI) reduction efficiency in the presence of all studied soils increased with increasing iron filings dosage and decreased with increasing the initial Cr(VI) concentration. The reaction rates considerably depended on pH and were higher in acidic soils. The diffusion parabolic model was the best kinetic model as evidenced by the highest determination coefficient (r2) and the lowest standard error of the estimate (SE). The rate-limiting step(s) may be transport of chromate anions across a liquid film at the interface of soil-liquid, transport in liquid-filled macropores of iron filings aggregates, or diffusion in micropores and along the particle's surface.
Related content
Batch Cr(VI) removal by polyacrylamide-grafted sawdust: Kinetics and thermodynamics
Water Research, Vol. 32, Iss. 12, 1998-12 ,pp. :
Development of iron-based nanoparticles for Cr(VI) removal from drinking water
EPJ Web of Conference, Vol. 40, Iss. issue, 2013-01 ,pp. :