Influence of bioenergy waste biochar on proton- and ligand-promoted release of Pb and Cu in a shooting range soil

Prasanna Kumarathilaka; Mahtab Ahmad; Indika Herath; Kushani Mahatantila; B C L Athapattu; Jörg Rinklebe; Yong Sik Ok; Adel Usman; Mohammad I Al-Wabel; Adel Abduljabbar; Meththika Vithanage

doi:10.1016/j.scitotenv.2017.12.294

Influence of bioenergy waste biochar on proton- and ligand-promoted release of Pb and Cu in a shooting range soil

Sci Total Environ. 2018 Jun 1:625:547-554. doi: 10.1016/j.scitotenv.2017.12.294. Epub 2017 Dec 30.

Authors

Affiliations

¹ Environmental Chemodynamics Research Group, National Institute of Fundamental Studies, Hantana Road, Kandy 20000, Sri Lanka.
² Soil Sciences Department, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia; Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan.
³ Industrial Technology Institute, Bauddhaloka Mawatha, Colombo 7, Sri Lanka.
⁴ Department of Civil Engineering, The Open University of Sri Lanka, Nugegoda 10250, Sri Lanka.
⁵ University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Soil- and Groundwater-Management, Pauluskirchstraße 7, 42285 Wuppertal, Germany; Department of Environment and Energy, Sejong University, Seoul 05006, Republic of Korea.
⁶ Korea Biochar Research Center, O-Jeong Eco-Resilience Institute (OJERI), Division of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea.
⁷ Soil Sciences Department, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia; Department of Soils and Water, Faculty of Agriculture, Assiut University, Assiut 71526, Egypt.
⁸ Soil Sciences Department, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia.
⁹ Industrial Psychology, College of Education, King Saud University, Riyadh, Saudi Arabia.
¹⁰ Environmental Chemodynamics Research Group, National Institute of Fundamental Studies, Hantana Road, Kandy 20000, Sri Lanka; Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka. Electronic address: meththika@sjp.ac.lk.

PMID: 29291569
DOI: 10.1016/j.scitotenv.2017.12.294

Abstract

Presence of organic and inorganic acids influences the release rates of trace metals (TMs) bound in contaminated soil systems. This study aimed to investigate the influence of bioenergy waste biochar, derived from Gliricidia sepium (GBC), on the proton and ligand-induced bioavailability of Pb and Cu in a shooting range soil (17,066mg Pb and 1134mg Cu per kg soil) in the presence of inorganic (sulfuric, nitric, and hydrochloric) and organic acids (acetic, citric, and oxalic). Release rates of Pb and Cu in the shooting range soil were determined under different acid concentrations (0.05, 0.1, 0.5, 1, 5, and 10mM) and in the presence/absence of GBC (10% by weight of soil). The dissolution rates of Pb and Cu increased with increasing acid concentrations. Lead was preferentially released (2.79×10^-13 to 8.86×10^-13molm^-2s^-1) than Cu (1.07×10^-13 to 1.02×10^-13molm^-2s^-1) which could be due to the excessive Pb concentrations in soil. However, the addition of GBC to soil reduced Pb and Cu dissolution rates to a greater extent of 10.0 to 99.5% and 15.6 to 99.5%, respectively, under various acid concentrations. The increased pH in the medium and different adsorption mechanisms, including electrostatic attractions, surface diffusion, ion exchange, precipitation, and complexation could immobilize Pb and Cu released by the proton and ligands in GBC amended soil. Overall, GBC could be utilized as an effective soil amendment to immobilize Pb and Cu in shooting range soil even under the influence of soil acidity.

Keywords: Amendment; Dissolution; Immobilization; Trace metal release.