title: Spectroscopic characterization of dissolved organic matter derived from different biochars and their polycylic aromatic hydrocarbons (PAHs) binding affinity.
abstract: In recent years, biochar has received a great attention due to its high application in different sectors of environment. The feasibility of biochar applications is depended on its physical and chemical properties and biochar-derived dissolved organic matter (DOM) characteristics. This study was conducted to investigate the spectroscopic characteristics of biochar-derived DOM and its binding capacity of hydrophobic organic chemicals (HOCs). DOM solutions were isolated from five different biochars prepared through pyrolysis and analyzed for dissolved organic carbon (DOC) contents. The optical analysis with UV-visible absorption and excitation-emission matrix (EEM) fluorescence spectroscopes and DOC water distribution coefficient (KDOC) were calculated in the presence of PAHs and DOM. The DOC contents and the estimated aromaticity (SUVA254) were different for selected biochars. The DOM derived from soybean straw biochar (SBBC) showed the highest DOC contents followed by rice straw biochar (RSBC). The SBBC and RSBC peak position in the fluorescence excitation/emission matrix at longer wavelength corresponded to the peak position of other three biochars indicating that SBBC and RSBC had relatively higher degree of humification. This was well correlated with the observed KDOC values, suggesting that the KDOC value(')s dominant factor was the degree of biochar-derived DOM humification. The results of this study indicate that the optical analysis may provide valuable information regarding the characteristics of biochar-derived DOM and its application as environmental amendments for minimization of toxic organic compounds.
authors.affiliation: Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; Ningbo Urban Environment Observation and Research Station, Chinese Academy of Sciences, Ningbo, 315800, China. Electronic address: jftang@iue.ac.cn.
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Tang
authors.affiliation: Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
authors.forename: Xinhu
authors.initials: X
authors.lastname: Li
authors.affiliation: Ningbo Municipal Research & Design Institute of Environmental Protection, Ningbo, 315012, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Li
authors.affiliation: Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; Department of Environmental Sciences, University of Peshawar, Peshawar, 25120, Pakistan. Electronic address: sardar.khan2008@yahoo.com.
authors.forename: Sardar
authors.initials: S
authors.lastname: Khan
mesh_terms: D002244:Carbon / Q000032:analysis; D002606:Charcoal / Q000737:chemistry*; D009930:Organic Chemicals / Q000737:chemistry*; D012275:Oryza; D013025:Glycine max; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D009930:Organic Chemicals; C540010:biochar; D002606:Charcoal; D002244:Carbon
keywords: Biochar; Dissolved organic carbon water distribution coefficient; Dissolved organic matter; Organic pollutants