ECA Technology
The Science
Electrochemical activation is a technology to produce meta-stable substances using unipolar (anodic or cathodic) electrochemical exposure for further usage of these substances in various technological processes while they still maintain physical-chemical and catalytic overactivity.
As a physico-chemical process, electrochemical activation is a combination of electrochemical and electrophysical actions (performed in conditions of minimal heat evolution) on liquid (mostly on water) containing ions and molecules of substances dissolved in it, in the area of spatial charge near the electrochemical system electrode (either anode, or cathode) surface during non-equilibribrium transfer of charge by electrons through the border "electrode - electrolyte".
As a result of electrochemical activation, water becomes meta-stable (activated) demonstrating for a few dozen hours an increased reactivity in various physical and chemical processes. Water activated by cathode (catholyte) acquires such characteristic as superactivity of electrons and a well-pronounced reductant quality. Correspondingly, water activated by anode (anolyte) is characterized by inhibited electron activity and manifests qualities as an oxidant.
Electrochemical activation makes it possible to purposefully change dissolved gases composition, acid-base and oxidative-reductive properties of water in wider limits than under equivalent chemical regulation, allows to synthesize meta-stable chemical reagents (oxidants or reductants) from water and substances dissolved in it. It is used in the processes of water purification and decontamination, as well as for transforming water or diluted electrolyte solutions into environmentally friendly anti-microbial, washing, extractive and other functionally useful solutions, including therapeutic.
Differences between physical-chemical properties of activated and non-activated solutions are illustrated by the results of studying the correlation between the degree of deviation of activated solution physical-chemical parameters from the equilibrium state, and intensity and deepness of electrochemical solution, as well as source solution mineralization.
The Chemistry
The principle chemical reactions that take place within the ECA cell reactor are:
O2 + H + e- HO2 E0 = - 0.13 V [1]
2H+ + 2e- H2 E0 = 0.00 V [2]
HO2 + H+ + e- H2O2 E0 = +1.50 V [3]
O3 + 2H+ + 2e- O2 + H2O E0 = +2.07 V [4]
OH- + H+ + e- H2O E0 = +2.85 V [5]
H2O + e- H+ OH- E0 = - 2.93 V [6]
OH+ e- OH- E0 = +2.02 V [7]
(E0 is the standard redox potential):
The equations above are not a complete list, but give examples of some of the reactions that can take place. Notably, they show that electrolysis of water produces H+ and OH ions, H and OH radicals, H2, O2, HO2, O3 and the like due to redox reactions. As a direct result of electrolysis, hydrogen and ozone gas are released and a percentage of hydroxides remain in the solution in various forms including, but not limited to, hydrogen peroxide.
The addition of sodium chloride (table salt) in the brine leads to the following additional reactions:
On the cathode side:
Na+ + e- Na [8]
2Na + 2H2O 2Na+ + 2OH- + H2 [9]
and at the anode side
2Cl- - 2e- Cl2 [10]
It should further be noted that the Cl2 and OH- can react as follows:
Cl2 + 2OH- ClO- + Cl- + H2O [11]
Cl2 + OH- HClO + Cl- [12]
(very minimally produced in ‘NEW’)
The general product specification of ‘NEW’ is:
- pH 6.5 –8.5*
- Oxidation-Reduction Potential (ORP) > 800mV
- Free Available Oxidants (FAOx) 50-500 ppm**
- EC 5-15ppm***
*the pH of ‘NEW’ can be adjusted by the operator from acidic to alkaline.
** the amount of free available chlorine can be adjusted by the operator.
*** varies with the amount of free available chlorine
Free Available Oxidants (FAOx) is essentially all chlorine species that are not combined with ammonia (or other nitrogenous compounds) to form chloramines.
The known chemical species present in ‘NEW’ are:
- Hypochlorous Acid (HOCl)
- Sodium Hypochlorite (NaClO)
- Sodium Chloride (NaCl)
Therefore, the HOCL concentration claimed in ‘NEW’ is believed to comprise of a combination of chlorine ions and not necessarily HOCL, where the concentrations of each chemical are determined by the current density, pH and other important process parameters.