Remediation of phenanthrene from contaminated kaolinite by electroremediation-Fenton technology

Abstract

Polycyclic aromatic hydrocarbons (PAHs) cause a high environmental impact when released into the environment. The objective of this study was to evaluate the capacity to decontaminate polluted soils with phenanthrene as a model PAH using a combination of two technologies: electrokinetic remediation and Fenton process. Kaolinite was used as a model sample that was artificially polluted at the laboratory at an initial concentration of phenanthrene of 500 mg kg(-1) of dried kaolinite. The standard electrokinetic process resulted in negligible removal of phenanthrene from the kaolinite sample. Faster and more efficient degradation of this compound can be promoted by introduction of a strong oxidant into the soil such as hydroxyl radicals. For this reason, the Fenton reactions have been induced in several experiments in which H(2)O(2) (10%) was used as flushing solution, and kaolinite polluted with iron was used. When anode and cathode chambers were filled with H(2)O(2) (10%), the kaolinite pH is maintained at an acid value around 3.5 without pH control and an overall removal and destruction efficiency of phenanthrene of 99% was obtained in 14 days by applying a voltage gradient of 3 V cm(-1). Therefore, it is evident that a combined technology of electrokinetic remediation and Fenton reaction is capable of simultaneously removing and degrading of PAHs in polluted model samples with kaolinite.

Remediation of contaminated marine sediment using electrokinetic–Fenton technology

“…Kim et al [40] utilized 7% H 2 O 2 and 0.01 N H 2 SO 4 in the anode chamber in the EKFenton treatment of kaolin polluted with phenanthrene. On the other hand, the effectiveness of the EK-Fenton technique to treat soils contaminated with PAHs has been proved by Alcá ntara et al [12]. They found that when anode and cathode chambers were filled with H 2 O 2 (10%) the overall removal and a destruction efficiency of phenanthrene of 99% were obtained in 14 days.…”

“…A substantial list of applications of electroremediation for the elimination of metals and some undesirable inorganic anions such as fluoride exists in the bibliography [3][4][5][6][7]. Also, in recent years several research groups have begun to analyze the application of this technology to soils contaminated by organic compounds, such as polycyclic aromatic hydrocarbons (PAHs) and benzene, toluene, ethylbenzene, and xylenes (BTEX) [8][9][10][11][12][13][14], phenol [15], organochlorates [16], trichloroethelene and tetrachloroethane [17] and dyes [18].…”

Decontamination of soils containing PAHs by electroremediation: A review

“…On the other hand, the effectiveness of the Electro-Fenton technique to treat soils contaminated with PAHs has been proved by Alcántara et al [74]. They found that when anode and cathode chambers were filled with H 2 O 2 (10%), the kaolin pH is maintained at an acid value around 3.5 without pH control and an overall removal and destruction efficiency of phenanthrene of 99% was obtained in 14 days.…”

Hybrid Technologies for the Remediation of Diesel Fuel Polluted Soil

“…Several studies [19,20,34,35], along with the authors' previous study [21], have reported that electrokinetic treatment can be combined with the Fenton reaction (EK-Fenton) to promote the removal of model organic compounds, such as phenanthrene or trichloroethylene. Based on these studies, a new experiment was developed with the aim of achieving total remediation of diesel fuel polluted soil (see Tab.…”

“…The Fenton reaction involves two steps: first, the decomposition of H 2 O 2 , which is catalyzed by Fe(II) and results in the generation of hydroxyl radicals, and, secondly, the degradation of organic pollutants by hydroxyl radicals via oxidation [19]. This technology has been used for the remediation of phenanthrene in a model soil such as kaolin [20,21] or mixture of sand and bentonite [22]. So far, only Tsai et al [23] have used this technology to remediate diesel fuel contaminated soil.…”