Wang Xiaohua, Liu Ni, Liu Yunguo, Jiang Luhua, Zeng Guangming, Tan Xiaofei, Liu Shaobo, Yin Zhihong, Tian Sirong, Li Jiang
College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.
Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
Int J Environ Res Public Health. 2017 Oct 11;14(10):1213. doi: 10.3390/ijerph14101213.
Rice straw biochar that produced at three pyrolysis temperatures (400, 500 and 600 °C) were used to investigate the adsorption properties of 17β-estradiol (E2). The biochar samples were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), elemental analysis and BET surface area measurements. The influences of pyrolysis temperature, E2 concentration, pH, ionic strength, background electrolyte and humic acid were studied. Kinetic and isotherm results illustrated that the adsorption process could be well described by pseudo-second-order and Freundlich models. Experimental results showed that ionic strength had less influence on the adsorption of E2 by 500 and 600 °C rice straw biochar. Further, multivalent ions had positive impact on E2 removal than monovalent ions and the influence of the pyrolysis temperature was unremarkable when background electrolyte existed in solutions. The adsorption capacity of E2 decreased with the pH ranged from 3.0 to 12.0 and the humic acid concentration from 2 to 10 mg L. Electrostatic attractions and π-π interaction were involved in the adsorption mechanisms. Compared to low-temperature biochar, high-temperature biochar exhibited a better adsorption capacity for E2 in aqueous solution, indicated it had a greater potential for E2 pollution control.
采用在三种热解温度（400、500和600℃）下制备的稻草生物炭，研究其对17β-雌二醇（E2）的吸附特性。通过扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）、元素分析和BET比表面积测量对生物炭样品进行了表征。研究了热解温度、E2浓度、pH值、离子强度、背景电解质和腐殖酸的影响。动力学和等温线结果表明，吸附过程可用准二级模型和Freundlich模型很好地描述。实验结果表明，离子强度对500℃和600℃稻草生物炭吸附E2的影响较小。此外，多价离子对E2去除的影响比单价离子更积极，当溶液中存在背景电解质时，热解温度的影响不显著。E2的吸附容量随pH值在3.0至12.0范围内以及腐殖酸浓度在2至10mg/L范围内而降低。吸附机制涉及静电吸引和π-π相互作用。与低温生物炭相比，高温生物炭在水溶液中对E2表现出更好的吸附容量，表明其在控制E2污染方面具有更大的潜力。
