Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Engineering Research Center of Environmental Diagnosis and Contamination Remediation, College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China.
School of Environment, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, China.
Environ Sci Pollut Res Int. 2019 Mar;26(9):8709-8720. doi: 10.1007/s11356-019-04320-0. Epub 2019 Feb 1.
In this work, biochar (BC), activated carbon (AC), and graphene oxide (GO) were thiol-functionalized using 3-mercaptopropyltrimethoxysilane (3-MPTS) (named as BCS, ACS, and GOS, respectively). BCS, ACS, and GOS were synthesized mainly via the interaction between hydrolyzed 3-MPTS and surface oxygen-containing functional groups (e.g., -OH, O-C=O, and C=O) and π-π interaction. The materials before and after modification were characterized and tested for mercury removal, including sorption kinetics and isotherms, the effects of adsorbent dosage, initial pH, and ionic strength. Pseudo-second-order sorption kinetic model (R = 0.9921.000) and Langmuir sorption isotherm model (R = 0.9640.998) fitted well with the sorption data of mercury. GOS had the most -SH groups with the largest adsorption capacity for Hg and CHHg (449.6 and 127.5 mg/g), followed by ACS (235.7 and 86.7 mg/g) and BCS (175.6 and 30.3 mg/g), which were much larger than GO (96.7 and 4.9 mg/g), AC (81.1 and 24.6 mg/g), and BC (95.6 and 9.4 mg/g). GOS and ACS showed stable mercury adsorption properties at a wide pH range (29) and ionic strength (0.010.1 mol/L). Mercury maybe removed by ligand exchange, surface complexation, and electrostatic attraction.
在这项工作中，生物炭（BC）、活性炭（AC）和氧化石墨烯（GO）被 3-巯丙基三甲氧基硅烷（3-MPTS）巯基化（分别命名为 BCS、ACS 和 GOS）。BCS、ACS 和 GOS 主要通过水解 3-MPTS 与表面含氧官能团（如-OH、O-C=O 和 C=O）和π-π相互作用之间的相互作用合成。对修饰前后的材料进行了表征和汞去除测试，包括吸附动力学和等温线、吸附剂用量、初始 pH 值和离子强度的影响。准二级吸附动力学模型（R=0.9921.000）和 Langmuir 吸附等温线模型（R=0.9640.998）很好地拟合了汞的吸附数据。GOS 具有最多的 -SH 基团，对 Hg 和 CHHg 的吸附容量最大（分别为 449.6 和 127.5mg/g），其次是 ACS（分别为 235.7 和 86.7mg/g）和 BCS（分别为 175.6 和 30.3mg/g），远大于 GO（96.7 和 4.9mg/g）、AC（81.1 和 24.6mg/g）和 BC（95.6 和 9.4mg/g）。GOS 和 ACS 在较宽的 pH 范围（29）和离子强度（0.010.1mol/L）下表现出稳定的汞吸附性能。汞可能通过配体交换、表面络合和静电吸引去除。
