Effect of humic acid (HA) on sulfonamide sorption by biochars

• Published in: Environmental pollution (1987) Vol. 204; pp. 306 - 312
• Main Authors: Lian, Fei, Sun, Binbin, Chen, Xi, Zhu, Lingyan, Liu, Zhongqi, Xing, Baoshan
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.09.2015
• Subjects: Adsorption; Biochar; Charcoal - chemistry; Concentration (composition); Contaminants; Fractionation; Humic acid; Humic acids; Humic Substances - analysis; Hydroxyapatite; Sorbates; Sorption; Sulfamethoxazole - chemistry; Sulfanilamides - chemistry; Sulfonamide; Surface properties; Sorption; Fractionation; Sulfonamide; Biochar; Humic acid
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2015.05.030

Effect of quantity and fractionation of loaded humic acid (HA) on biochar sorption for sulfonamides was investigated. The HA was applied in two different modes, i.e. pre-coating and co-introduction with sorbate. In pre-coating mode, the polar fractions of HA tended to interact with low-temperature biochars via H-bonding, while the hydrophobic fractions were likely to be adsorbed by high-temperature biochars through hydrophobic and π-π interactions, leading to different composition and structure of the HA adlayers. The influences of HA fractionation on biochar sorption for sulfonamides varied significantly, depending on the nature of interaction between HA fraction and sorbate. Meanwhile, co-introduction of HA with sulfonamides revealed that the effect of HA on sulfonamide sorption was also dependent on HA concentration. These findings suggest that the amount and fractionation of adsorbed HA are tailored by the surface properties of underlying biochars, which differently affect the sorption for organic contaminants. [Display omitted] •Effect of quantity and fractionation of coated HA on sorption of sulfonamides by BC was studied.•Fractionation of coated HA is tailored by surface properties of BC.•Roles of HA in BC sorption depend on interaction between HA adlayer and sorbate.•Roles of HA in sulfonamide sorption by BC also depend on HA aqueous concentration. The quantity and fractionation of adsorbed HA play a major role in sulfonamide sorption by biochars.