Effects of Biochar Produced from Cornstalk, Rice Husk and Bamboo on Degradation of Flumioxazin in Soil.

Application of biochar provide a novel approach against organic contaminated soil issues. The objective of this study was to evaluate the effect of biochars amendment on flumioxazin degradation using batch experiments. A simple and accurate pretreatment method coupled with liquid chromatography tandem with mass spectrometry was developed and successfully applied on the assessment trials of the effect of biochar amendment on the degradation of flumioxazin in soil. Three different types of biochar were characterized in terms of the degradation of flumioxazin in soil. The results demonstrated that flumioxazin degraded fast in four nonbiochar soil sample (half-lives of 11.1–20.8 days) but slower in biochar soils (half-lives of 15.4–30.7 days), and the effect varied with the nature of feedstock and pyrolysis temperature. Biochars prepared at 500°C (CB500 and RB500) could remove flumioxazin more effectively than the biochar prepared at 700°C (BB700). In addition, biochar content also affected the remediation. When the biochar content changed, the degradation rate of flumioxazin varied significantly. The degradation of flumioxazin was faster in soil samples with 0.5% cornstalk biochar than those in nonbiochar soil samples. As the biochar content increased, the degradation rate decreased because of the dominant adsorption efficiency. The results in this study support the environmental risk assessment of flumioxazin in soil and provide some guidance for biochar amendment in soil contaminated with flumioxazin. [ABSTRACT FROM AUTHOR]