Zhang Shuai, Yeerkenbieke Gulijiazi, Shi Shuai, Wang Zhaoyang, Yi Lijin, Lu Xiaoxia
Ministry of Education Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
Toxics. 2024 Mar 29;12(4):251. doi: 10.3390/toxics12040251.
Polycyclic aromatic hydrocarbons (PAHs) and arsenic (As) are common pollutants co-existing in the environment, causing potential hazards to the ecosystem and human health. How their behaviors are affected by micro/nano particles in the environment are still not very clear. Through a series of static adsorption experiments, this study investigated the adsorption of pyrene and arsenite (As (III)) using micro/nano carbon black and iron oxide under different conditions. The objectives were to determine the kinetics and isotherms of the adsorption of pyrene and As (III) using micro/nano carbon black and iron oxide and evaluate the impact of co-existing conditions on the adsorption. The microstructure of micro/nano carbon black (C 94.03%) is spherical-like, with a diameter of 100-200 nm. The micro/nano iron oxide (hematite) has irregular rod-shaped structures, mostly about 1 µm long and 100-200 nm wide. The results show that the micro/nano black carbon easily adsorbed the pyrene, with a pseudo-second-order rate constant of 0.016 mg/(g·h) and an adsorption capacity of 283.23 μg/g at 24 h. The micro/nano iron oxide easily adsorbed As (III), with a pseudo-second-order rate constant of 0.814 mg/(g·h) and an adsorption capacity of 3.45 mg/g at 24 h. The mechanisms of adsorption were mainly chemical reactions. Micro/nano carbon black hardly adsorbed As (III), but its adsorption capability for pyrene was reduced by the presence of As (III), and this effect increased with an increase in the As (III) concentration. The adsorbed pyrene on the micro/nano black carbon could hardly be desorbed. On the other hand, the micro/nano iron oxide could hardly adsorb the pyrene, but its adsorption capability for As (III) was increased by the presence of pyrene, and this effect increased with an increase in the pyrene concentration. The results of this study provide guidance for the risk management and remediation of the environment when there is combined pollution of PAHs and As.
多环芳烃（PAHs）和砷（As）是环境中常见的共存污染物，对生态系统和人类健康造成潜在危害。它们在环境中的行为如何受到微/纳米颗粒的影响仍不太清楚。通过一系列静态吸附实验，本研究考察了在不同条件下使用微/纳米炭黑和氧化铁对芘和亚砷酸盐（As（III））的吸附情况。目的是确定使用微/纳米炭黑和氧化铁吸附芘和As（III）的动力学和等温线，并评估共存条件对吸附的影响。微/纳米炭黑（C 94.03%）的微观结构呈球状，直径为100 - 200纳米。微/纳米氧化铁（赤铁矿）具有不规则的棒状结构，大多长约1微米，宽100 - 200纳米。结果表明，微/纳米炭黑容易吸附芘，在24小时时的准二级速率常数为0.016毫克/（克·小时），吸附容量为283.23微克/克。微/纳米氧化铁容易吸附As（III），在24小时时的准二级速率常数为0.814毫克/（克·小时），吸附容量为3.45毫克/克。吸附机制主要是化学反应。微/纳米炭黑几乎不吸附As（III），但其对芘的吸附能力因As（III）的存在而降低，且这种影响随着As（III）浓度的增加而增大。微/纳米炭黑上吸附的芘几乎无法解吸。另一方面，微/纳米氧化铁几乎不吸附芘，但其对As（III）的吸附能力因芘的存在而增强，且这种影响随着芘浓度的增加而增大。本研究结果为PAHs和As复合污染时的环境风险管理和修复提供了指导。
