hello anton
>
>Here are some references on electrolyzed water that might be of interest.
thx
Israilides CJ. Vlyssides AG. Mourafeti VN. Karvouni G.
OLIVE OIL WASTEWATER TREATMENT WITH THE USE OF AN ELECTROLYSIS
SYSTEM
Bioresource Technology. 61(2):163-170, 1997 Aug.
Olive oil wastewater (OOW), a toxic liquid associated with the
production of olive oil, was treated by an electrochemical
method using Ti/Pt as anode and Stainless Steel 304 as cathode.
In this technique, sodium chloride 4% (w/v) as an electrolyte
was added to the wastewater and the mixture was passed through
an electrolytic cell. Due to the strong oxidizing potential Of
(i warned about this ^^^^^^^^^)
the chemicals produced (chlorine oxygen, hydroxyl radicals and
other oxidants) the organic pollutants were wet oxidized to
carbon dioxide and water. A number of experiments were run in a
batch, laboratory-scale, pilot-plant, and the results are
reported here. After 1 and 10 h of electrolysis at 0.26
A/cm(2), total COD was reduced by 41 and 93%, respectively,
total TOC was reduced by 20 and 80.4%, VSS were reduced by 1
and 98.7%, and total phenolic compounds were reduced by 50 and
99.4%, while the mean anode efficiency was 1960 gh(-1) A(-1)
sq.m(-1) and 340 g h(-1) A(-1) sq.m(-1). Also, the mean energy
consumption was 1.273 kwh per kg of COD removed and 12.3 kwh
per kg of COD removed for 1 and 10 h, respectively. These
results strongly indicate that this electrolytic method of
total oxidation of OOW is not feasible. However it could be
used as an oxidation pretreatment stage for detoxification of
the wastewater.
here's a technical explanation from a chemist:
Renger G.
MECHANISTIC AND STRUCTURAL ASPECTS OF PHOTOSYNTHETIC WATER
OXIDATION
Physiologia Plantarum. 100(4):828-841, 1997 Aug.
Conclusions on the functional and structural organisation of
photosynthetic water oxidation are gathered from a critical
survey of the wealth of data reported in the literature and
author's own experimental research: (1) the water oxidising
complex (WOC) contains a tetranuclear manganese cluster of
'dimer of dimers' structure and functional heterogeneity of the
metal centers, (2) the four step univalent oxidative pathway
leading to water oxidation into molecular oxygen and four
protons comprises only manganese, tyrosine Y-Z of polypeptide
D1 and the substrate as redox active species, (3) the redox
transitions S-0 --> S-1 and S-1 --> S-2 are manganese centered
whereas S-2 --> S-3 is most likely a ligand-centered reaction,
(4) there exist several lines of evidence for a marked
structural change that accompanies the redox transition S-2 -->
S-3, (5) one Ca2+ is an indispensible constituent of a
functionally competent WOC while the role of Cl- is much less
clear and a direct participation disputable, (6) substrate
water is most likely bound in all redox states S-0,...,S-3 and
exchangeable with the bulk phase. The protonation state is
determined by the redox state S-i and the protein
microenvironment. A mechanism is proposed for water oxidation
in the WOC that is based on three key postulates: (1) water
oxidation takes place in the first coordination sphere of one
manganese dimer [MnaMnb]; (2) the essential O-O bond is
preformed in S-3 as part of a rapid redox isomerism S-3(I) <->
S-3(II) where in S-3(II) a nuclear geometry and electronic
configuration is attained that corresponds to a peroxidic-type
species; and (3) S-3(II) is an 'entatic state' for the
formation of complexed dioxygen triggered by Y-Z(OX) induced
electron abstraction from the WOC and electronic redistribution
to S-0(O-2). [References: 93]
these two show, that it may very well have a "cleaning" effect
on water:
Kannan N. Sivadurai SN. Berchmans LJ. Vijayavalli R.
REMOVAL OF PHENOLIC COMPOUNDS BY ELECTROOXIDATION METHOD
Journal of Environmental Science & Health, Part A:
Environmental Science & Engineering & Toxic & Hazardous
Substance Control. 30(10):2185-2203, 1995.
The present study envisages a method to remove phenol from the
phenolic effluents by the electrooxidation under alkaline
conditons. Synthetic effluent containing phenol (100 ppm) is
subjected to electrolysis under various experimental conditions
inorder to find out the optimum conditions for the removal of
phenol. An electrolysis cell was designed with graphite
electrodes and electrolysis was carried out under galvanostatic
conditions keeping the total quantity of current at 0.75 A h.
The reduction in concentration of phenol was analysed in terms
of COD. Continuous electrolysis was also carried out at optimum
conditions (current density: 4 A dm(-2), phenol: 100 ppm and
supporting electrolyte. 1M NaOH) to find out the maximum
removal of phenol. The removal of phenol from phenolic
effluents is found to be highly efficient to the extent of
98.55%. The electrooxidation of phenol at anode leads to the
formation of carbon di-oxide and water. The study reveals that,
the phenol can be almost completely oxidised at the graphite
anode with a maximum current efficiency of 17%. It is concluded
that, the phenol can be removed from phenolic effluents
effectively by electrooxidation method. [References: 7]
Allen SJ. Khader KYH. Bino M.
ELECTROOXIDATION OF DYESTUFFS IN WASTE WATERS
Journal of Chemical Technology & Biotechnology. 62(2):111-117,
1995 Feb.
An electrochemical oxidation cell is used to reduce the
concentrations of organic dyes and chemical oxygen demand in an
aqueous effluent. The importance of the presence of an
electrolyte is recorded and the effects of changing both
electrolyte concentration and initial dye concentration are
reported. The rate of the electrooxidation process is shown to
be a pseudo-first-order kinetic process with the rate constant
being affected by both the electrolyte concentration and the
dye concentration. The use of different electrolytes is
reported. [References: 11]
i did not doubt, that these effects exist, i only said, that
20.000$ for such a device are a rip-off.
klaus
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