全氟化合物（PFCs）是一类环境持久性有机污染物，广泛分布在各种环境介质中，例 如污泥、土壤、沉积物、水体、空气和人体。其中碳原子数为 8 的全氟辛酸 (PFOA)和全 氟磺酸 (PFOS)是检出量最高的化合物。本文以 PFOA 和 PFOS 为目标污染物，采用电絮 凝和电吸附技术研究了水中 PFCs 的去除机理。 针对工业废水中 PFCs 浓度高的特征，采用电絮凝技术进行系统研究。电絮凝实验结 果表明，锌作为阳极对水中 PFCs 的去除效果要远高于镁、铝和铁，经过 10 min 的电解， 电絮凝原位产生的氢氧化锌絮体对 PFOA 的去除率和吸附容量分别为 96.7%和 4.7 mmol g −1。采用锌板作为阳极、不锈钢作为阴极时，在 20 mM 的 Cl-、NO3 -、SO4 2-和 CO3 2- /HCO3 - 离子存在时，经过 20 min 的电解，PFOA 的去除率分别为 99.7%、98.1%、96.2%和 4.1%。 当采用锌板作为阳极、铝作为阴极时，在 20 mM 的 Cl-、NO3 -、SO4 2-和 CO3 2- /HCO3 -离子存 在时，经过 20 min 的电解，PFOA 的去除率分别为 98.9%、97.3%、7.4%和 4.6%。不同离 子存在条件下，电絮凝原位产生絮体的物理化学性质差异导致去除机理的不同， Zn0.70Al0.30(OH)2(CO3)0.15·xH2O 和 ZnO（Na2CO3 作为电解质时，电絮凝原位产生氢氧化锌 絮体除外）这两种电絮凝原位产生的结晶体能促进 PFOA 的吸附。当溶液中存在 CO3 2- /HCO3 -离子时，采用电絮凝原位产生的絮体作为吸附剂，有助于提高 PFOA 的去除率。 通过超声法、溶剂法、加热法、过硫酸钾氧化和电催化技术对电絮凝原位产生的絮体 中高浓度的 PFCs 进行去除研究。结果表明，使用 40 KHz 频率的超声处理 120 min 后，PFOA 的回收率为 3.0%；0.01 m mol L-1 HCl 和 100°C 高温处理可有效分离电絮凝絮体中高浓度 的 PFCs，回收率分别为 94.2%和 99.9%；当 PFOA 和 PFOS 溶液中存在 5%的异丙醇时， 经过 100°C 高温处理 10 h，电絮凝絮体中高浓度 PFCs 的回收率分别为 97.2%和 97.4%；在 80°C 条件下，使用浓度为 20 g L-1 的过硫酸钾处理电絮凝絮体中高浓度的 PFOA，经过 6 h 的氧化处理，PFOA 的去除率为 97.3%；使用 Ti/SnO2-Sb 电极电催化处理电絮凝絮体中高 浓度 PFOA，在 20 mA cm -2 的电流密度下处理 90 min，其 PFOA 的去除率为 98.2%。电催 化处理后得到的中间产物为短碳链的 PFCAs。 吸附技术可以快速去除水中的不同浓度的 PFCs，活性炭纤维（ACF）作为吸附剂对 PFOA 的去除率要大于粉末活性炭（PAC）、颗粒活性炭（GAC）和碳纳米管（CNT）。 经过 6 h 的吸附，ACF 对 PFOA 的去除率和吸附容量分别为 99.5%和 117.9 mg g-1。ACF 对 PFOA 的吸附平衡时间和最大吸附容量分别是 6 h 和 400.6 mg g-1。疏水作用是 ACF 吸附 PFCs 过程中最主要的机理，溶液中的 PFCs 形成半胶团和胶团进一步促进其吸附作用。但 是采用 Ti/ACF 作为电吸附材料，在不同电压条件下，Ti/ACF 电极对 PFCs 无电增强作用。采用电泳沉积法分别制备 Ti/CNT 和 Ti/Ebonex/CNT 电极，实验结果表明， Ti/Ebonex/CNT 具有更高的稳定性。当复合电极中石墨烯（Graphene）含量为 20%时具有 最佳的电化学特性和电吸附性能，且对 PFOA 的去除率和吸附容量均高于 Ti/ACF 电极、 Ti/CNT 电极和 CNT-PAC 复合电极。经过 4 h 的电吸附实验，CNT-20% Graphene 对 PFOA 的去除率和吸附容量分别为 96.9%和 2421.7 μg g-1。CNT-20% Graphene 电极对 PFOA 和 PFOS 的电吸附平衡时间分别为 4 h 和 2 h，与 CNT-20% Graphene 材料的吸附实验相比， 吸附初始速率分别提高了 9.7 倍（PFOA）和 12.7 倍（PFOS）。在 1.5 V 的电压下，CNT-20% Graphene 电极对 PFOA 和 PFOS 的最大吸附容量分别是 491.9 mg g-1 和 555.8 mg g-1，与 CNT-20% Graphene 材料的吸附实验相比，最大吸附容量分别提高了 205.0 倍（PFOA）和 88.2 倍（PFOS）。溶液 pH 值、电压和极板间距对电吸附效率具有显著地影响，在电场作 用下形成的双电层是电吸附去除溶液中 PFCs 的主要机理。

Perfluorinated compounds (PFCs) are environmentally refractory organic pollutants that have been widely detected in various environmental matrices including sludge, soil, sediment, water, air, and human. Perfluorooctanoate (PFOA, C7F15COOH) and perfluorooctane sulfonic acid (PFOS) are most frequently detected PFCs in these products. In this study, electrocoagulation and electrosorption techniques were chosen to investigate the removal mechanism of PFCs. Electrocoagulation behaviors of PFCs from industrial wastewater were investigated. The removal ratio of PFOA by hydroxide flocs generated in-situ in the electrocoagulation process using the zinc anode was higher than those of magnesium, aluminum, and iron anodes. The removal ratio and sorption capacity of PFOA by hydroxide flocs generated in-situ in the electrocoagulation process using the zinc anode was 96.7% and 4.7 mmol g−1 after 10 min electrolysis. The removal ratios of PFOA were 99.7%、98.1%、96.2% and 4.1% in the electrocoagulation process using zinc as anode and stainless steel as cathode in the presence of Cl- , NO3 - , SO4 2- and CO3 2- /HCO3 - (20 mM) after 20 min electrolysis, respectively . For aluminum as cathode, the removal ratios of PFOA were 98.9%、97.3%、7.4% and 4.6% in the electrocoagulation process in the presence of Cl- , NO3 - , SO4 2- and CO3 2- /HCO3 - (20 mM) after 20 min electrolysis, respectively. The different removal ratios of PFOA during the electrocoagulation process were primarily because the hydroxide flocs generated in-situ was different in the presence of diverse ions. We firstly demonstrated that Zn0.70Al0.30(OH)2(CO3)0.15·xH2O and ZnO generated in-situ in the electrocoagulation process (except for CO3 2- /HCO3 - ) using zinc anode and aluminum/stainless steel cathode governed the sorption of PFOA. The adsorbent hydroxide flocs in-situ generated in the presence of Clcan effectively remove PFOA from aqueous solution containing CO3 2- /HCO3 - anion. These results provided an effective and alternative method to remove PFOA from aqueous solution containing CO3 2- /HCO3 - anion. The high concentration of PFCs from hydroxide flocs generated in-situ in the electrocoagulation process was purified by ultrasonic, solvent method, heating method, potassium sulfate oxidation and electro-catalytic oxidation technologies. The removal ratio of PFOA was 3.0% by ultrasonic method with the frequency of 40 KHz after 120 min treatment. 0.01 m mol L-1 HCl and 100°C treatments can effectively recycle PFCs from the hydroxide flocs generated in-situ in the electrocoagulation process, and the removal ratios of PFOA were 94.2% and 99.9%, respectively. The recovery of PFCs exhibited slight effect with the addition of 5% isopropanol, and the removal ratios of PFOA and PFOS were 97.2% and 97.4% after 100°C treatment, respectively. The high concentration of PFCs from hydroxide flocs generated in-situ in the electrocoagulation process was effectively removed by potassium persulfate oxidation and electro-catalytic oxidation. The removal ratio of PFOA was 97.3% after potassium persulfate oxidation treatment with the concentration of 20 g L-1 . The removal ratio of PFOA from the hydroxide flocs was 98.2% after 90 min of electro-catalytic oxidation at a current density of 20 mA cm-2 . Moreover, the intermediate products of PFOA by electro-catalytic oxidation treatment were short carbon chain of PFCAs. Sorption experiment can quickly remove PFCs from aqueous solution at a concentration from a few μg g-1 to several hundred mg L-1 . The sorption capacity value of PFOA decreased in the order of activated carbon fibre (ACF)＞powdered activated carbon (PAC)＞granular active carbon (GAC)＞carbon nanotube (CNT). The removal ratio and sorption capacity of PFOA on ACF were 99.5% and 117.9 mg g-1 after 6 h sorption experiments. The sorption of PFOA on ACF followed pseudo-second-order kinetics and the sorption equilibrium was reached approximately 6 h. The maximum sorption capacity of PFOA by ACF was 400.6 mg g -1 . However, the electric enhancement of PFOA was not effective with Ti/ACF electrode. Ti/CNT and Ti/Ebonex/CNT electrodes were prepared by electrophoretic deposition method, and the results showed that Ti/Ebonex/CNT electrode had higher stability than Ti/CNT electrode. It was found that the CNT with 20 wt% graphene (CNT-20% Graphene electrode) had the best capacitive behavior and electrochemical property. The removal ratio and sorption capacity of PFOA on CNT-20% Graphene electrode were higher than those of Ti/ACF electrode, Ti/CNT electrode and CNT-PAC composite electrode. The removal ratio and sorprion capacity of PFOA on CNT-20% Graphene electrode were 96.9% and 2421.7 μg g-1 after 4 h electrosorption experiment. The sorption equilibrium times of PFOA and PFOS by CNT-20% Graphene electrode were approximately 4 h and 2 h, respectively. Compared with the sorption experiments on CNT-20% Graphene material, the adsorption rate increased 9.7-fold (PFOA) and 12.7-fold (PFOS). The maximum sorption capacities of PFOA and PFOS on CNT-20% Graphene electrode were 491.9 mg g-1 and 555.8 mg g-1 , respectively. Compared with the sorption experiments on CNT-20% Graphene material, the maximum sorption capacity increased 205.0-fold (PFOA) and 88.2-fold (PFOS). The solution pH, voltage and plate distance affected the removal ratios of PFOA by electrosorption. The mechanism of electrosorption was the double electric layer which was formed with the electric field.