Department of Environmental Science and Ecological Engineering, Korea University, Seoul, 02841, South Korea.
Department of Environmental Engineering, Chosun University, Gwangju, 61452, South Korea.
Environ Sci Pollut Res Int. 2018 Sep;25(26):25681-25689. doi: 10.1007/s11356-017-9049-7. Epub 2017 Apr 28.
Agricultural soil was treated with biochar (5% w/w) produced from two pyrolysis temperatures (400 and 700 °C) of giant Miscanthus (GMC-400 and GMC-700, respectively), and the subsequent sorption of sulfathiazole (STZ) was evaluated as a function of pH (2, 5, and 7) and aging period (0, 3, and 6 months). Because sorption was nonlinear, with 0.51 < N < 0.75, the linearized sorption coefficient (K ) was used for the comparison across samples. The K of GMC-400 treatment (3.96-9.96 L kg) was higher than that of GMC-700 treatment (1.27-3.38 L kg). In laps of aging period over 6 months, the sorption of GMC-400-treated soil had gradually increased to be 3.3 times higher than that of untreated soil, whereas there was no statistical difference for GMC-700 treatment. Results of FTIR and SEM analyses revealed that the number of O-containing functional groups in the GMC-400 treatment increases and the micropores of GMC-700 are deformed over time. Sorption was also pH-dependent in the order of pH 2 > pH 5 > pH 7. The sorption hysteresis (H) index for the GMC-400 treatment was higher at pH 7 (3.99) than at pH 5(2.53), and both values had increased after 6 months (4.18 and 3.17, respectively). The results of this study clearly demonstrate that the sorption of STZ on GMC-treated soils is greatly enhanced, mainly through the greater micropore surfaces, the abundance of hydrophilic functional groups over time, and π-π electron donor-acceptor interaction at low pH.
农业土壤用两种热解温度（400 和 700°C）制备的巨芒草生物炭（分别为 GMC-400 和 GMC-700，按 5%重量比）进行处理，并评估了磺胺噻唑（STZ）在不同 pH（2、5 和 7）和老化期（0、3 和 6 个月）下的吸附情况。由于吸附是非线性的，0.51<N<0.75，因此使用线性化吸附系数（K ）来比较不同样品。GMC-400 处理的 K 值（3.96-9.96 L kg）高于 GMC-700 处理的 K 值（1.27-3.38 L kg）。在 6 个月的老化期间，GMC-400 处理的土壤吸附逐渐增加到未处理土壤的 3.3 倍，而 GMC-700 处理则没有统计学差异。FTIR 和 SEM 分析结果表明，GMC-400 处理中含 O 官能团的数量增加，GMC-700 的微孔随时间变形。吸附也随 pH 值的增加而增加，顺序为 pH 2>pH 5>pH 7。GMC-400 处理的吸附滞后（H）指数在 pH 7（3.99）时高于 pH 5（2.53），并且在 6 个月后这两个值都有所增加（分别为 4.18 和 3.17）。本研究结果清楚地表明，GMC 处理土壤对 STZ 的吸附大大增强，主要是通过随时间增加的更大的微孔表面积、丰富的亲水官能团以及在低 pH 值下的π-π电子给体-受体相互作用。
