title: Impact of low molecular weight organic acids (LMWOAs) on biochar micropores and sorption properties for sulfamethoxazole.
abstract: The interaction between biochar (BC) and antibiotics with the presence of low molecular weight organic acids (LMWOAs) is largely unknown, although it is crucial for understanding the role of BC in reducing the bioavailability of antibiotics in rhizosphere. The impacts of two typical LMWOAs (citric and malic acids) on sorption of sulfamethoxazole (SMX) by crop-straw BCs produced at 300 °C (BCs300) and 600 °C (BCs600), respectively, were examined. The sorption of SMX on BCs increased more than 5 times with the concentration of LMWOAs increasing from 0 to 100 mmol/L, which was mainly attributed to the elevated microporosity of BCs (measured by CO2) after treated by LMWOAs. The pore development of BCs was mainly derived from the release of dissolved organic residues from BC by LMWOA washing. For H2O2-oxidized BCs, however, LMWOAs had little effect on SMX sorption by BCs300 but greatly increased that by BCs600, which can be explained by the distinct sorption mechanisms of SMX on BCs300 and BCs600. These results indicate that the impact of LMWOAs on SMX sorption is highly dependent on the properties of BCs and LMWOAs, as well as their interaction mechanisms.
authors.affiliation: Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, China; College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
authors.forename: Binbin
authors.initials: B
authors.lastname: Sun
authors.affiliation: Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, China. Electronic address: lianfei2000@gmail.com.
authors.forename: Fei
authors.initials: F
authors.lastname: Lian
authors.affiliation: Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, China.
authors.forename: Qiongli
authors.initials: Q
authors.lastname: Bao
authors.affiliation: Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, China.
authors.forename: Zhongqi
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, China.
authors.forename: Zhengguo
authors.initials: Z
authors.lastname: Song
authors.affiliation: College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
authors.forename: Lingyan
authors.initials: L
authors.lastname: Zhu
mesh_terms: D000327:Adsorption; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D001682:Biological Availability; D002606:Charcoal / Q000737:chemistry*; D019343:Citric Acid / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D008293:Malates / Q000737:chemistry*; D058441:Rhizosphere; D013420:Sulfamethoxazole / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D008293:Malates; C540010:biochar; D002606:Charcoal; D019343:Citric Acid; C030298:malic acid; D006861:Hydrogen Peroxide; D013420:Sulfamethoxazole
keywords: Biochar; Low molecular weight organic acid; Pore structure; Sorption; Sulfamethoxazole