Details

Autor(en) / Beteiligte

• Carvalho de Almeida, C.
• Muñoz-Morales, M.
• Sáez, C.
• Cañizares, P.
• Martínez-Huitle, C.A.
• Rodrigo, M.A.

Titel

Electrolysis with diamond anodes of the effluents of a combined soil washing – ZVI dechlorination process

Ist Teil von

• Journal of hazardous materials, 2019-05, Vol.369, p.577-583

Ort / Verlag

Netherlands: Elsevier B.V

Erscheinungsjahr

2019

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• •Combination of ZVI dehalogenation and soil washing in a single stage is feasible.•The type and concentration of iron used determine the soil washing composition.•Anodic oxidation is an efficient treatment for soil washing wastes.•Dechlorinated species in the waste leads to lower efficiency in the electrolysis. In this work, a new soil washing process in which Soil-Liquid extraction technology is enhanced by adding iron particles (zero valent iron nanoparticles or granules) was investigated to remove clopyralid from spiked soils. This novel approach can be efficiently used to extract chlorinated hydrocarbons from soil and aims to obtain soil-washing wastes with low content of hazardous chlorinated species. The iron particles used were subsequently removed from the treated soil using magnetic fields. Then, the complete mineralization of the produced soil washing effluents was successfully achieved by applying anodic oxidation with diamond anodes in an electrochemical flow cell. Results demonstrated that, opposite to what it was initially expected, no improvements in the efficiency of the electrochemical process were observed by adding iron particles during the soil washing. This behavior is explained in terms of the lower electrochemical reactivity of the dechlorinated derivatives produced. Although results are not as promising as initially expected, it does not mean a completely negative outcome for the use of ZVI during washing, because the hazardousness of the pollutants is rapidly decreased in the initial stages of the soil-washing, opening the possibility for the combination of this technology with other processes, such as biological treatment.