S. B. Gupta, H. Bluhm
Forschungszentrum Karlsruhe,
Institute for Pulsed Power and Microwave Technology (IHM), PO Box: 3640 D-76021
Karlsruhe, Germany; Email: suryakant.gupta@ihm.fzk.de
Abstract
Because of undesirable
side effects of chemical methods pulsed underwater corona discharges are
emerging as a potential future advanced oxidation process (A.O.P.) for water
disinfection. In pulsed corona discharges a discharge channel is created, which
contains a non-thermal plasma with a low degree of ionisation and low electron
densities. but with electron energies of up to 10 eV. It has been demonstrated
that electrons with this energy can dissociate water and oxygen molecules and
produce various reactive radicals (•OH, H•, O•, HO•2), molecular species (H2O2,
H2, O2), ultraviolet radiation and shock waves. It is supposed that the combination of all effects leads to a very
efficient killing of microorganisms. To understand this in detail and to improve the efficiency of the
overall system there is a need of development of suitable diagnostic methods
for the quantitative determination of
the various oxidants produced during the discharge. In this paper we are going
to present preliminary experimental results obtained with different chemical
probes for •OH radicals, and H2O2 produced by pulsed corona discharges.