Reclamation of zinc-contaminated soil using a dissolved organic carbon solution prepared using liquid fertilizer from food-waste composting.
A liquid fertilizer obtained through food-waste composting can be used for the preparation of a dissolved organic carbon (DOC) solution. In this study, we used the DOC solutions for the remediation of a Zn-contaminated soil (with Zn concentrations up to 992 and 757 mg kg(-1) in topsoil and subsoil, respectively). We then determined the factors that affect Zn removal, such as pH, initial concentration of DOC solution, and washing frequency. Measurements using a Fourier Transform infrared spectrometer (FT-IR) revealed that carboxyl and amide were the major functional groups in the DOC solution obtained from the liquid fertilizer. Two soil washes using 1,500 mg L(-1) DOC solution with a of pH 2.0 at 25°C removed about 43% and 21% of the initial Zn from the topsoil and subsoil, respectively. Following this treatment, the pH of the soil declined from 5.4 to 4.1; organic matter content slightly increased from 6.2 to 6.5%; available ammonium (NH4(+)-N) content increased to 2.4 times the original level; and in the topsoil, the available phosphorus content and the exchangeable potassium content increased by 1.65 and 2.53 times their initial levels, respectively.
Experimental Forest, National Taiwan University, Chushan, Nantou County, 55750, Taiwan.
Po-Neng
PN
Chiang
Department of Environment Engineering, College of the Environment and Ecology, and The Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, Xiamen University, Xiamen, P.R. China.
Ou-Yang
OY
Tong
Department of Environmental Engineering, National Ilan University, Ilan 26047, Taiwan.
Chyow-San
CS
Chiou
Department of Environmental Engineering, National Ilan University, Ilan 26047, Taiwan.
Yu-An
YA
Lin
Department of Animal Science, National Ilan University, Ilan 26047, Taiwan.
Ming-Kuang
MK
Wang
Department of Agricultural Chemistry, National Taiwan University, Taipei 10617, Taiwan. Electronic address: ccliu@niu.edu.tw.
Cheng-Chung
CC
Liu
D002244:Carbon / Q000737:chemistry*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D005308:Fertilizers; D005502:Food; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000032:analysis / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry*; D012996:Solutions; D014866:Waste Products
D005308:Fertilizers; D008670:Metals; D012987:Soil; D012989:Soil Pollutants; D012996:Solutions; D014866:Waste Products; D002244:Carbon
Dissolved organic carbon; Food-waste composting; Liquid fertilizer; Soil washing; Zinc