MADRID Rossana Elena
congresos y reuniones científicas
Shock electrodialysis phenomenon for sustainable separation devices through a fluidic system
MONTES, PAULA; TREJO GONZÁLEZ, JOSÉ A.; ARAOZ, EMILSE; PEREZ, SOFÍA; TRUJILLO, RICARDO M.; MADRID, ROSSANA; ADOLFO ÁVILA
Congreso; II Brazil-Argentine Microfluidics Congress and V Congreso de Microfluídica Argentina; 2019
The availability of biomassassociated with agroindustry residues provides enormous opportunities for newbioproducts applications for sustainable processes. Biochar is a cost-effectivecarbonaceous material which can serve as raw material to create new separationagents and microdevices for gas purification, water treatment, biomoleculeseparation, controlled drug delivery, electrochemical reactors, microseparatorsand many other advanced applications. In this work, we used biochar disksderived from biomass harvest residues as a porous media to study the shockelectrodialysis phenomenon in a home-made cell for continuous electrolyte flow of2 mL in volume. The cell includes two stainless steel electrodes to study thisphenomenon (Fig.1). Comparative cyclic voltammetry measurements were performedusing the cell in batch mode with 0.1 mM KCl solution either including or notincluding the biochar porous media. The difference between both voltammetryprofiles showed the additional diffusion limitation of the current densityprovided by the porous material. A set of continuous flow runs considering 0.1mM KCl solution (~17 µS/cm) were performed under an applied electric potential rangingfrom 0.2 to 5.0 V and different flow rates between 0.1 to 10.0 mL/min. Thecontinuous monitoring of the solution ion conductivity in the cell outletthroughout each run provided important insights. The decrease of the outlet ionconductivity when the electric potential was applied to the cell indicated thepresence of ion concentration polarization through the biochar porous material.The polarization effect increased when flow rates and electrolyteconcentrations were lower. Much sharper conductivity drops were observed forflows in the order of 100 µL/min (Fig. 2). Miniaturized systems could beapplied in tissue or organ engineering for fluids treatment. With a properengineering design and scale (geometry, thickness and morphology) andconsidering optimized operating conditions (flow rate, applied voltage and ionconcentration), this cost-effective carbonaceous material may play an importantrole in the development of new separation technologies for water treatment.