Wang Ying, Zhang Zhichen, Yin Zhihang, Wang Jun, Zhang Xiaojian, Chen Chao
State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Suzhou 215163, China.
J Environ Sci (China). 2025 Jan;147:101-113. doi: 10.1016/j.jes.2023.10.016. Epub 2023 Oct 25.
Control of N-nitrosodimethylamine (NDMA) in drinking water could be achieved by removing its precursors as one practical way. Herein, superfine powdered activated carbons with a diameter of about 1 µm (SPACs) were successfully prepared by grinding powdered activated carbon (PAC, D=24.3 µm) and applied to remove model NDMA precursors, i.e. ranitidine (RAN) and nizatidine (NIZ). Results from grain diameter experiments demonstrated that the absorption velocity increased dramatically with decreasing particle size, and the maximum increase in k was 26.8-folds for RAN and 33.4-folds for NIZ. Moreover, kinetic experiments explained that rapid absorption could be attributed to the acceleration of intraparticle diffusion due to the shortening of the diffusion path. Furthermore, performance comparison experiments suggested that the removal of RAN and NIZ (C=0.5 mg/L) could reach 61.3% and 60%, respectively, within 5 min, when the dosage of SAPC-1.1 (D=1.1 µm) was merely 5 mg/L, while PAC-24.3 could only eliminate 17.5% and 18.6%. The adsorption isotherm was well defined by Langmuir isotherm model, indicating that the adsorption of RAN/NIZ was a monolayer coverage process. The adsorption of RAN or NIZ by SAPC-1.1 and PAC-24.3 was strongly pH dependent, and high adsorption capacity could be observed under the condition of pH > pk+1. The coexistence of humic acid (HA) had no significant effect on the adsorption performance because RAN/NIZ may be coupled with HA and removed simultaneously. The coexistence of anions had little effect on the adsorption also. This study is expected to provide an alternative strategy for drinking water safety triggered by NDMA.
去除饮用水中的N-亚硝基二甲胺（NDMA）前体是实现其控制的一种可行方法。在此，通过研磨粒径为24.3 µm的粉末活性炭（PAC）成功制备了直径约为1 µm的超细粉末活性炭（SPACs），并将其用于去除NDMA模型前体，即雷尼替丁（RAN）和尼扎替丁（NIZ）。粒径实验结果表明，随着粒径减小，吸附速率显著提高，RAN的k值最大增加26.8倍，NIZ的k值最大增加33.4倍。此外，动力学实验表明，快速吸附归因于扩散路径缩短导致颗粒内扩散加速。进一步的性能比较实验表明，当SAPC-1.1（D = 1.1 µm）的投加量仅为5 mg/L时，在5分钟内对RAN和NIZ（C = 0.
