Modeling the Kinetic Equations in Describing the Release Rate of Lead in a Naturally Contaminated Calcareous Soil Treated with Different Biochars

Document Type : Research Paper

Authors

1 Department of Soil Science, Faculty of Agriculture, Shahr-e-kord University, Shahr-e-kord, Iran.

2 water and soil unit, agricultural research, education and extension organization,, Shahr-e-kord, Iran.

Abstract

Mining activities provide a pathway for the entry and accumulation of heavy metals in soil. Utilization of biochars could remediate such contaminated soils. Therefore, in this study, the impact two percent of different wastes and biochars (prepared at temperature of 600 °C) was investigated on the availability and release kinetics of lead in polluted soil. Sandy loam calcareous soil, which was collected near Bama lead and zinc mine located in Sepahan Shahr city, was treated with residues and biochars and incubated for 120 days. Then the availability and release kinetics of lead were measured in control and treatments extracting with diethylenetriaminepentaacetic acid solutions (DTPA-TEA) during 504 hours. Results showed that treating soils with biochars, decreased the bioavailablaty and release kinetics of Pb significantly in comparison with control. The comparison of the coefficient of explanation (R2) and the standard error of estimation (SEE) of equations showed that simple Elovich equations, power function and first order equations had the highest coefficient of explanation and the lowest standard error of estimate for control and treated soils. So, these mathematical equations have been useful in explaining the cumulative release and release rate of Pb. Values of 1/β (derived from the simplified Elovich equation) and b (derived from the power function equation) changed from 161.47 – 237.18 mg kg-1 h-1 and 0.245 – 0.299 mg kg-1 h-1, respectively. Correlation analysis study, between DTPA-Pb with constants illustrated that among the constants, “K1”, “1/β”, “b”, and “a*b” were better parameters to predict the release kinetics of Pb.

Keywords

Main Subjects

Iranian Journal of Soil and Water Research

Articles in Press, Accepted Manuscript
Available Online from 15 April 2024

Files

Share

How to cite

Statistics