need for multidisciplinarity in water treatment is … · 2016-12-23 · •fluoropolymers for...
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NEED FOR MULTIDISCIPLINARITY IN WATER TREATMENT –IS TREATMENT ENOUGH?
Prof. Ulla Lassi, Research Unit of Sustainable Chemistry, University of Oulu
Prof. Riitta Keiski, Environmental and Chemical Engineering, University of Oulu
Prof. Kirsi Vähäkangas, University of Eastern Finland
University of Oulu
AOPI PROJECT
12/14/20162
1. Model compounds2. Industrial wastewaters
University of Oulu
MAINOBJECTIVES
12/14/20163
1) Determination the compositions of wastewaters in pharmaceutical and
food industry
2) Evaluation of health effects of selected industrial effluents and possible
reaction by-products of the wastewater treatment process
3) Conducting a sustainability assessment analysis of the processes to
be developed
4) Development of a hybrid method for the treatment of food and
pharmaceutical industries’ wastewaters by photocatalysis and catalytic
wet air oxidation
University of Oulu
Model compounds
12/14/20164
P-coumaric acid
Diuron• Pesticide
Phthalic anhydride• Plasticizer
Perfluoro-octanoic acid• Fluoropolymers for non-stick surfaces
Bisphenol A• Plasticizer
University of Oulu
Wastewater samples
12/14/20165
Sample WWP1:
• Industrial wastewater
• High amount of organic compounds
• TOC ~30 g/l, pH 6
Sample WWP2:• Industrial wastewater
• Main organic compound ethanol, also other
alcohols and ketones
• TOC 7.6 g/l, pH > 12
University of Oulu
Catalytic wet air oxidation (CWAO)
12/14/20166
Intermediates (e.g. carboxylic acids)
+ CO2 + H2O
Organic compounds
of wastewater
• High organic concentration (e.g. pharmaceutical and food industry)
• Contain non-biodegradable compounds
• Homogeneous (metal salts)
• Heterogeneous o Carbon materials
o Transition metals (Cu, Mn, Co, Cr, V, Ti)
o Noble metals (Pt, Ru, Ir, Ag) supported on metal oxides (CeO2, TiO2, ZrO2 etc.)
130-200 °C + 5-50 bar
+ catalyst
University of Oulu
Photocatalytic degradation of organic pollutants
12/14/20167
Heterogenous Photocatalysis
• An emerging technique valuable for water purificationand remediationSuitable for the abatement of low concentrations of
contaminants, also non-biodegradable compounds
Not a selective method
A semiconductor with a favourable band gap energy, primarily metal oxides or sulphides
Energy of electrons and holes (potential) determines the photocatalytic activity and
usefulness for a particular reaction
Selection of the right semiconductor or combination of semiconductors and metals
Process needs:• A strong oxidizing agent (molecular O2) and H2O• A semiconductor photocatalyst• UV-irradiation
Nearly complete mineralization is achieved for many organic compounds (http://www.greenearthnanoscience.com/what-is-photocatalyst.php)
University of Oulu
CWAO of WWP1
12/14/20168
• Sample volume 160 ml
• Temperature 160 °C
• Oxidizer compressed air (total pressure 20/50 bar)
• Mixing speed 500 rpm
• Catalyst load 4 g L-1
• Reaction time 3 h
The schematic representation of wet air oxidation system.
• Laboratory prepared
• Noble metals on mixed oxides
Active metals: Ag, Pt (2.5 wt%)
Mixed oxides (i. e. supports): Ce-Zr, Ce-Ti
University of Oulu
CWAO of WWP1 - results:
12/14/20169
p [bar] pH catalyst Highest TOC removal [%]
20 initial - 15 (180 min)
20 initial CeO2 30 (180 min)
20 initial Ce0.2Zr0.8O2 30 (90 min)
20 initial Ag/Ce0.85Zr0.15O2 40 (90 min)
50 13 - 17 (150 min)
50 initial CeO2 55 (150 min)
50 initial Ce0.8Ti0.2O2 44 (after heating)
50 initial Pt/CeO2 30 (90 min)
50 initial Pt/Ce0.8Ti0.2O2 44 (60 min)
Degree of biodegradation after treatment
University of Oulu
Photocatalytic degradation of organic pollutants
12/14/201610
0
20
40
60
80
100
0 25 50 75 100 125 150 175 200
Rem
oval
(%
)
Time (min)
Diuron
PCOU
PHA
a) Distilled water
The photocatalytic degradation of four organic pollutants were studied over TiO2 P25 in
distilled water and in a wastewater matrix obtained from (the) pharmaceutical industry.
P-coumaric acid (PCOU) is a phenolic
compound typically found in agro-industrial
effluents, olive pressing and wine distillery
wastewaters.
Phthalic anhydride (PHA) is released to the
environment from the chemical industry, mainly from
the manufacturing of PHA and from the production of
plasticizers, surfactants and pesticides.
Diuron is one of the most commonly
used herbicides in agriculture.
(Pirilä M, Saouabe M, Ojala S, Drault F, Valtanen A, Huuhtanen M, Brahmi R, Keiski RL. Photocatalytic
degradation of organic pollutants in wastewater.–Topics in Catalysis 58(14), 1085-1099)
Bisphenol A (BPA) is an important organic
chemical used for the production of various
polycarbonate and epoxy resins and as a
plasticizer.
0
20
40
60
80
100
0 25 50 75 100 125 150 175 200
Rem
oval
(%
)
Time (min)
Diuron
PCOU
PHA
BPA
b) Wastewater matrix
University of Oulu
Comparing two different photocatalysts
12/14/201611
0
20
40
60
80
100
120
0 50 100 150 200
Rem
oval
(%)
Time (min)
TOC removal
a) ZnO
0
20
40
60
80
100
120
0 50 100 150 200
Rem
oval
(%)
Time (min)
TOC removal
b) TiO2 P25
• The following catalysts were used in the presence of UV-A irradiation with the
concentration of 200 mg/l
• TiO2 (Aeroxide P25, Degussa)
• ZnO nanopowder (Sigma-Aldrich)
• A model solution of BPA with the concentration of 15 mg/l
University of Oulu
Aromatase (CYP19A1) enzyme
12/14/201612
‒ The most abundant CYP enzyme in
the human placenta
‒ Catalyzes estrogen formation from
androgens
‒ Can metabolize also many
xenobiotics
‒ The effect of wastewater (WW) on the
aromatase enzyme
100 % wastewater inhibited aromatase activity
statistically significantly (p<0.05, one-way ANOVA
with Tukey’s post-hoc)Control
1 µM
Finro
zole
0,1 µM
Finro
zole
20 %
WW
40 %
WW
100 % W
W
0
50
100
150***
******
Aro
matase a
ctiv
ity
(%
of
co
ntro
l)
n = 3
Effect of wastewater on aromatase activity
University of Oulu
The effect of model compounds on the aromatase activity – no effect
12/14/201613
Bisphenol A
0.1 µM
Finro
zole
1 µM
Finro
zole
0.1 µM
BPA
1 µM
BPA
10 µM B
PA
0
50
100
150
Aro
matase a
ctiv
ity
(%
of
co
ntro
l)
Diuron
0.1 µM
Finro
zole
1 µM
Finro
zole
1 µM
Diuro
n
10 µM D
iuro
n
50 µM D
iuro
n
0
50
100
150A
ro
matase a
ctiv
ity
(%
of
co
ntro
l)
University of Oulu
CASE :Treatment of bisphenol A (BPA)
12/14/201614
‒ Several catalytic materials were tested both in photocatalysis and CWAO:
Catalyst BPA removal [%]
Photocatalysis, UV-B, after 3h CWAO
Aeroxide TiO2-P25 commercial catalyst 100 37
TiO2-60099
n.d.
TiO2-500 96 27
TiO2-N-600 97 n.d.
TiO2-N-500 96 n.d.
ZrO2 67 33
CeO2 56 98
Ti0.5Zr0.5O2 85 33
Ti0.8Ce0.2O2 64 94
Ag/ TiO2-P25 100 n.d.
Pt/Ti0.8Ce0.2O2 89 99
CeO2+TiO2 Mech. mixture 100 89
University of Oulu
CASE :Treatment of bisphenol A (BPA)
12/14/201615
‒ Pt/Ti0.8Ce0.2O2 and CeO2-TiO2 mechanical mixture was chosen as catalyst in the
consecutive tests (photocatalysis after CWAO)
‒ Cell viability were analysed in MCF-7 cells after individual and consecutive tests
‒ Over 80% removal of BPA with both catalysts
‒ Initial BPA solution decreased the cell viability
‒ After treatment: no effect to the cell viability
University of Oulu
Conclusions
12/14/201616
‒ A multidisciplinary approach is needed to understand the effects of (catalytic)
treatments on the removal of selected organic compounds from wastewaters
‒ Selected model compounds and corresponding industrial wastewaters
originated from pharmaceutical and food industry
‒ Health effects of selected industrial effluents and possible reaction by-
products of the wastewater treatment process were evaluated
‒Model solutions of Diuron, PFOA and BPA have no effect on the cellular
activity (aromatase enzyme activity) indicating that steroid hormone synthesis
is not disturbed by these compounds
‒ After the two stage treatment (CWAO+photocatalysis) of aqueous BPA
solution, the cell viability of MCF-7 was not affected while the untreated BPA
solution decreased the cell viability
University of Oulu
AOPI PROJECT – IN BRIEF
12/14/201617
3 PhD theses9 M.Sc. theses
12 peerly-reviewed publicationsSeveral manuscripts
Over 20 conference presentations2 visiting PhD researchers (tot. 2.5 years)
1 visiting professorSeveral research visits
THANK YOU FOR YOUR ATTENTION!
Contact information:
Professor Ulla Lassi, University of Oulu
eMail: [email protected]
Tel: +358 400 294 090