Electrocoagulation as the Key for an Efficient Concentration and Removal of Oxyfluorfen from Liquid Wastes

Abstract

Electrocoagulation is usually applied to remove pollutants from the liquid phase, but in this work it is investigated to concentrate pollutants, with the final aim to get a later much more efficient treatment by electrolysis. Results obtained during the treatment of wastes polluted with commercial oxyfluorfen (Fluoxil®) show that electrocoagulation exhibits a good efficiency in removing this model non-ionic halogenated pesticide. It was observed that the chemicals contained in Fluoxil® with higher solubility than oxyfluorfen are less efficiently removed, explaining the lower removal of TOC as compared to that of oxyfluorfen. An improvement in the design of the electrocoagulation was faced by increasing the amount of particles in the reactor, allowing to deplete the pesticide concentration down to levels 2-log below the inlet concentration. The herbicide is concentrated in a solid phase, from where it can be released to a concentrated waste just by changing the pH.

Improving a Redox Flow Battery Working under Realistic Conditions by Using of Graphene based Nanofluids

“…Thus, the stability of the prepared electrolytes based on nanofluids with carbonaceous nanoparticles was evaluated by Z potential measurements. The magnitude of the Z potential is a measurement of the surface charge of particles of the colloidal system ,. If all the particles in suspension have a large negative or positive Z potential value, then they will tend to repel each other and there will not be tendency for the particles to aggregate and hence they will not precipitate.…”

A new strategy for the electrolytic removal of organics based on adsorption onto granular activated carbon

“…Taking into account the very high cost of the electricity, a pre-concentration stage would be very useful in the search of more efficient technologies. This is the goal of several of the research lines that are currently carried out in our Lab, in which we are trying to develop new technologies applicable to the treatment of colloids [14], ionic pollutants [15] and other organics. In this work, we are proposing to combine Granular Activated Carbon (GAC) -adsorption with electrolysis.…”

Membrane preconcentration as an efficient tool to reduce the energy consumption of perfluorohexanoic acid electrochemical treatment

“…The concentrations of PFASs in environmental media are usually very low [3,25], that leads to mass-transfer controlled electrooxidation kinetics, thus constraining the efficiency of the electrochemical process [21]. Pre-concentration strategies such as electrocoagulation [26] and membrane separation [14,27,28] have been proposed to overcome this limitation. Membrane separation such as nanofiltration (NF) and reverse osmosis could play a key role optimizing the electrochemical treatment of persistent PFASs due to the facts that: (i) it allows increasing PFASs concentration in the retentate whilst at the same time the volume to be electrolyzed is drastically reduced.…”