Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6317286 | Environmental Pollution | 2013 | 8 Pages |
Abstract
Sorption of sulfonamides on biochars is poorly understood, thus sulfamethoxazole (SMX) sorption on biochars produced at 300-600 °C was determined as a function of pH and SMX concentration, as well as the inorganic fractions in the biochars. Neutral SMX molecules (SMX0) were dominant for sorption at pH 1.0-6.0. Above pH 7.0, although biochars surfaces were negatively-charged, anionic SMX species sorption increased with pH and is regulated via charge-assisted H-bonds. SMX0 sorption at pH 5.0 was nonlinear and adsorption-dominant for all the biochars via hydrophobic interaction, Ï-Ï electron donor-acceptor interaction and pore-filling. The removal of inorganic fraction reduced SMX sorption by low-temperature biochars (e.g., 300 °C), but enhanced the sorption by high-temperature biochars (e.g., 600 °C) due to the temperature-dependent inorganic fractions in the biochars. These observations are useful for producing designer biochars as engineered sorbents to reduce the bioavailability of antibiotics and/or predict the fate of sulfonamides in biochar-amended soils.
Related Topics
Life Sciences
Environmental Science
Environmental Chemistry
Authors
Hao Zheng, Zhenyu Wang, Jian Zhao, Stephen Herbert, Baoshan Xing,