Zhang Ping, O'Connor David, Wang Yinan, Jiang Lin, Xia Tianxiang, Wang Liuwei, Tsang Daniel C W, Ok Yong Sik, Hou Deyi
School of Environment, Tsinghua University, Beijing 100084, China; National Engineering Research Centre of Urban Environmental Pollution Control, Beijing Key Laboratory for Risk Modeling and Remediation of Contaminated Sites, Beijing Municipal Research Institute of Environmental Protection, Beijing 100037, China.
School of Environment, Tsinghua University, Beijing 100084, China.
J Hazard Mater. 2020 Feb 15;384:121286. doi: 10.1016/j.jhazmat.2019.121286. Epub 2019 Sep 24.
Adsorbents that effectively remove dye substances from industrial effluents are needed for the protection of human health and the natural environment. However, adsorbent manufacture is associated with secondary environmental impacts. In this study, a green biochar/iron oxide composite was produced using a facile approach involving banana peel extract and FeSO. The modified biochar's capacity to adsorb methylene blue (MB) was considerably enhanced (Langmuir Q of 862 mg/g for MB when C = 500 mg/L, pH = 6.1, T =313 K) compared to the unmodified banana peel biochar, and exhibited good performance for a wide range of pH values (pH 2.05-9.21). The Langmuir isotherm model and pseudo second-order kinetic model accurately describe the adsorption process. The material properties and corresponding adsorption mechanisms were investigated by various experimental techniques. Enhanced MB adsorption by the biochar/iron oxide composite is attributed to increased electronic attraction to MB molecules, as evidenced by XPS analysis. High adsorption capacity was retained after 5 regeneration cycles. This study suggests that biochar can be modified by a green synthesis approach to produce biochar/iron oxide composite with good MB removal capacity.
为保护人类健康和自然环境，需要能有效去除工业废水中染料物质的吸附剂。然而，吸附剂的制造会带来二次环境影响。在本研究中，采用一种简便方法，利用香蕉皮提取物和硫酸亚铁制备了一种绿色生物炭/氧化铁复合材料。与未改性的香蕉皮生物炭相比，改性生物炭对亚甲基蓝（MB）的吸附能力显著增强（当C = 500 mg/L、pH = 6.1、T = 313 K时，MB的Langmuir Q为862 mg/g），并且在很宽的pH值范围（pH 2.05 - 9.21）内表现出良好性能。Langmuir等温线模型和伪二级动力学模型准确地描述了吸附过程。通过各种实验技术研究了材料特性及相应的吸附机制。XPS分析表明，生物炭/氧化铁复合材料对MB吸附增强归因于对MB分子的电子吸引力增加。经过5次再生循环后仍保留了高吸附容量。本研究表明，生物炭可通过绿色合成方法改性，以制备具有良好MB去除能力的生物炭/氧化铁复合材料。
