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This work focuses on the removal of perchloroethylene (PCE) from gaseous streams using absorbers connected with electrolyzers. Two types of absorption devices (jet absorber and absorption column) were compared. In addition, it has been evaluated the different by-products generated when a simultaneous electrolysis with diamond anodes is carried out. PCE was not mineralized, but it was transformed into phosgene that mainly derivates into carbon tetrachloride. Trichloroacetic acid was also formed, but in much lower amounts. Results showed a more efficient absorption of PCE in the packed column, which it is associated to the higher gas–liquid contact surface. Jet absorber seems to favor the production of carbon tetrachloride in gaseous phase, whereas the packed column promotes a higher concentration of trichloroacetic acid in liquid. It was also evaluated the scale up of the electrolytic stage of these electro-absorption devices by using a stack with five perforated electrode packages instead of a single cell. Clarification of the effect of the applied current density on the speciation attained after the electrolysis of the absorbent has been attempted. Experiments reveal similar results in terms of PCE removal and a reduced generation of gaseous intermediates at lower current densities.

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The aim of this work was to implement a coupled system, a monopolar Electrocoagulation (EC)-Electrooxidation (EO) processes, for the treatment of soft drink wastewater. For the EC test, Cu-Cu, anode-cathode were used at current densities of 17, 51 and 68 mA cm. Only 37.67% of chemical oxygen demand (COD) and 27% of total organic carbon (TOC) were removed at 20 min with an optimum pH of 8, this low efficiency can be associated with the high concentration of inorganic ions which inhibit the oxidation of organic matter due to their complexation with copper ions. Later EO treatment was performed with boron-doped diamond-Cu electrodes and a current density of 30 Am. The coupled EC-EO system was efficient to reduce organic pollutants from initial values of 1875 mg L TOC and 4300 mg L COD, the removal efficiencies were 75% and 85%, respectively. Electric energy consumption to degrade a kilogram of a pollutant in the soft drink wastewater using EC was 3.19 kWh kg TOC and 6.66 kWh kg COD. It was concluded that the coupled system EC-EO was effective for the soft drink wastewater treatment, reducing operating costs and residence time, and allowing its reuse in indirect contact with humans, thus contributing to the sustainable reuse as an effluent of industrial wastewater.