17 / 25
Page 70
Industrial Chemistry | ISSN: 2469-9764 | Volume 4
17
th
International Conference on
May 21-22, 2018 | New York, USA
Industrial Chemistry and Water Treatment
Ind Chem 2018, Volume 4
DOI: 10.4172/2469-9764-C1-009
Ozone initiated inactivation of
Escherichia coli
and
Staphylococcus aureus
in water: Influence of
selected organic solvents prevalent in wastewaters
Ofori Isaac
University of KwaZulu-Natal, South Africa
O
zone absorption, stability, and reactivity in water are critical distinguishing factors for efficiency in either micropollutants
abatement or microbial inactivation. These are also largely, a function of the nature of the dissolved organic matter in the
water matrix. In the present study, the influence of four water-soluble organic solvents commonly discharged from industrial
lines into wastewater systems viz; ethanol, methanol, ethyl acetate and dimethyl sulfoxide (DMSO) on the ozone facilitated
inactivation of
Escherichia coli
(ATCC 25218) and
Staphylococcus aureus
(29213) in water was explored. An ozone bubbling-
time dependent absorption (up to 12min) and decomposition rate monitored spectrophotometrically in the presence of
2.5% and 5% concentrations of each organic solvent with their consequent effect on bacteria inactivation were determined.
The inactivation kinetics were described by the Efficiency Factor Home model. Relatively, higher residual concentrations of
absorbed ozone per unit bubbling time were obtained for the solutions of ethyl acetate and DMSO in comparison to methanol
and ethanol. Ozone stability was significantly enhanced in solutions containing DMSO or ethyl acetate which was characterized
by a lower pseudo- first order decomposition rate constant in DMSO (k
d
=3.381x10
-2
M
-1
s
-1
) and ethyl acetate (k
d
=4.45 x10
-2
M
-
1
s
-1
) solutions and in contrast with methanol (k
d
=1.13 x10
-1
M
-1
s
-1
), where the rate of decomposition was rather accelerated.
The faster absorption and stability of ozone in ethyl acetate and DMSO corresponded with an observed increase in the log
inactivation of
E. coli
and
S. aureus
by approximately 2-folds in relation to methanol at comparable conditions. These findings
are significant to the determination or prediction of the lifetime of ozone for efficient disinfection or pollutants oxidation in
industrial wastewater treatment systems.
ofass2006@yahoo.co.uk