Coupling Gliding Discharge Treatment and Catalysis by Oyster Shell Powder for Pollution Abatement of Surface Waters

Abstract

Adsorption on oyster shell powder (OS) was combined with gliding electric discharge to abate pollution of surface waters sampled in brooks passing through large Cameroonian cities and collecting industrial and domestic wastes. OS powder incorporated into the aqueous samples after exposure to the discharge improved pollutant abatement as compared to the plasma treatment alone. The process kinetics involved pseudo zero-order reactions for treatments longer than 5 min. Total organic carbon linearly decreases with increasing exposure time to the discharge (k ≈ 0.13 mgC L−1 min−1 for a 1 g L−1 standard OS charge). The rate constant linearly increases with the incorporated OS mass, which increases the sample pH. The coupled process is more efficient than a single plasma treatment of the polluted liquid in terms of operation cost, waste abatement ratio, and reaction rate. A chemical model involving known plasma generated species and matching acid−base effects is proposed.

Direct and post-discharges in environmental applications of cold plasmas

“…This is the case of brewery [14] and slaughterhouses [15] waste waters or more generally of surface waters [16]. Waste waters from food industry plants such as breweries settled in developing countries may be poured out in brooks without having been previously purified and may then deeply modify local environment.…”

Phenol decomposition in water cathode of DC atmospheric pressure discharge in air

“…A promising technique is the application of various types of gaseous discharges, the so-called advanced oxidation technologies (AOT). To date, many devices have been tested for this purpose (e.g., corona discharge over solution surface [1], contact glow discharge electrolysis [2,3], pulsed streamer discharge in or above solution [4,5], dielectric barrier discharge [6,7] and gliding arc [8]). At the same time, the data on DC discharge at atmospheric pressure with a liquid cathode are rather limited in spite of the fact that such discharge is the simplest for technical realization.…”

Application of Dielectric Barrier Discharge for Waste Water Purification

“…Discharges where plasmas can come in direct contact with the solution are the most attractive because in this case it is possible to use the most part of plasma active species more completely. Different types of discharges and setups have been used for these purposes including discharges with one or two liquid electrodes [1][2][3], pulse positive streamer corona discharge generated in aqueous solutions [4,5] and dielectric barrier discharge (DBD) [6][7][8].…”