Improvement of known electrochemical systems and technologies

Purification, decontamination and conditioning of water in EMERALD devices. There exist electrochemical technologies of drinking water purification in EMERALD devices of different types, their flow charts being quite different due to initial water chemical composition diversity, and to different requirements to quality and chemical composition of purified water. A common feature of all water purification technologies in EMERALD-type devices is that initial water arrives in the electrochemical system consisting of connected in a different order flow-through reactors – electrochemical (FEM), flotation, electro-kinetic, catalytic – where it undergoes consecutive stages of transformation securing removal of heavy metal ion elimination, organic compound oxidation and eradication of all types and species of microorganisms (bacteria, mycobacteria, viruses, fungi, spores), as well as microbial toxins.
Technologies of synthesizing electrochemically activated solutions in STEL devices. STEL devices meant for medical purposes are engineering electrochemical systems for producing electrochemically activated washing and antimicrobial solutions – anolyte and catholyte featuring high functional activity and environmental friendliness. Any STEL device contains a flow-through electrochemical diaphragm-type reactor made up of FEM modules, a hydraulic circuit to feed source solution to the reactor and to discharge the products of electrochemical synthesis from the reactor, as well as a power supply source. Besides, STEL devices may be supplied with a system automatically controlling the device's operation parameters, an automated system of periodic rinsing with an acid solution and a number of other gadgets and facilities that determine the degree of STEL device engineering sophistication. There have been developed and launched into commercial production STEL devices with the output of all types of activated solutions (acid and neutral anolyte, alkaline and neutral catholyte) from 10 to 1000 liters per hour. The degree of their technical excellence depends on their ability to produce activated solutions of as low mineralization as possible (permissible sodium chloride content of initial aqueous solution ranging from 0.5 to 5.0 g/l) with the highest possible anolyte oxidants' content and the highest possible catholyte reductive potential value (minus 700 – minus 800 mV relative to silver chloride reference electrode) and its lowest possible mineralization (preferably not exceeding 1.5 g/l).
Technology of water decontamination in field conditions in AQUADEZ devices. AQUADEZ devices are based on electrochemical technologies of water decontamination using auxiliary electrolyte in the cathodic chamber of FEM module. That guarantees maximum (up to 20 liters per hour for a single FEM module) output while decontaminating fresh water from surface water sources including bog water with minimum power consumption and under most unfavorable conditions of the devices' operation. There are AQUADEZ devices fitted with reactors the number of FEM-3 modules in which varies from 1 to 12, their output ranging between 10 and 250 liters per hour of decontaminated water at 40 - 500 Wt.
Technologies of decontamination and conditioning of swimming-pool water in ALLIGATOR-type devices. Similarity of technologies in this class is determined by the goal and the way to achieve it , i.e., each technology envisages synthesis of antimicrobial components directly from swimming pool water in an electrochemical device using no source chemicals. Also, a common feature of water treatment technologies in ALLIGATOR-type devices is the possibility of gradual elimination of hardness salts from swimming pool water in the process of the device's operation making it soft and agreeable.
Technology of oxidant solution production in AQUACHLOR devices. AQUACHLOR devices are intended for producing oxidant mixture solution from an aqueous sodium chloride solution. The devices are manufactured as modules producing 30- 500 g of oxidant mixture per hour. AQUACHLOR devices are based on a new technological process of sodium chloride solution electrolysis – ion-selective electrolysis with diaphragm (ISED), thus combining high cost-effectiveness and complete operational safety in one device. To produce 1 kg of oxidant mixture in terms of molecular chlorine in an AQUACHLOR device, no more than 2.0 kg of sodium chloride dosed into the AQUACHLOR device reactor, in the anodic chambers of compact-size flow-through modular cells under pressure from 0.8 to 1.2 kgf/cm 2 , a humid gaseous oxidant mixture is synthesized, including chlorine (95%), chlorine dioxide (3%), and ozone (2%), which immediately after generation is mixed with water in the ejector mixer of AQUACHLOR device forming oxidant mixture which, unlike common chlorine water or sodium hypochlorite solution, produces no chlorination by-products (trihalomethanes) while interacting with organic compounds in the treated water. AQUACHLOR devices are an alternative compact-size and highly-effective source of oxidant mixture, and can be used instead of cylinders and containers with liquid chlorine and, actually, instead of chlorinators at household and drinking water treatment plants, at local water purification facilities, at household and industrial sewage treatment plants, in swimming pool water purification systems both as single modules, and as a unit of modules connected into a single hydraulic system with specified oxidant output ranging from 30 g per hour to hundreds of kg per hour.

Development of new electrochemical systems and technologies

Below there are listed some technologies, whose effectiveness has been confirmed in industrial or laboratory conditions, and each of which is an object of investment development.

Technology of generating nitrogen and phosphoric fertilizers in irrigation water. The technology is realized by cathodic treatment of irrigation water and introduction into it of very small batches of nitrogenous and phosphoric acid mixture dissolved in anolyte until рН » 7. Large-scale production of nitrogen and phosphoric fertilizers is no longer needed, and consequently there is no need to transport and introduce them into soil. Cropping capacity increases, nitrite and nitrate content in fruits and vegetables is reduced down to its natural level typical for plants growing in ecologically safe environment.
Technology of spent lead accumulator renewal. A cathodically activated and heavily diluted sulfuric acid solution is poured into accumulator, and then is brought to desired density by adding concentrated sulfuric acid. Service life of new and worn out accumulators increases by 15- 45%, “charge-discharge” capacity increases by 20- 30%.
Technology of uranium and trans-uranium elements' leaching from beds. Reservoir water is subjected to anodic treatment, after which it is mixed with sulfuric acid and is re-injected into the bed. Tenfold economy of sulfuric acid is ensured, and useful leaching product yield increases by 10%.
Technology of profound electrochemical treatment of seawater accompanied by producing marketable chemical products: sodium hydroxide solution, hydrochloric acid, sulfuric acid. Seawater undergoes electrochemical treatment by ion-selective diaphragm-type electrolysis, due to which it is divided into sulfuric acid and sodium hydroxide solutions (their concentrations depending on source water mineralization), as well as into gases: chlorine and hydrogen supplied to the reactor for hydrochloric acid production. The technology allows chemical agent production directly on site, for instance, at offshore oil fields and separate drilling platforms) using only electric power and seawater. Power consumption does not exceed 5 kW ? h per 1 kg of chlorine.
Technology of precious metals extraction from spent catalysts of motorcar exhaust afterburning. Activated anolyte and catholyte of potable tap water or very weak acid and alkali solutions are used to prepare solutions of agents in the processes of chemical extraction of precious metals (platinum, iridium and rhodium) from spent catalysts. Saving of acids and alkali is above tenfold, and metal yield approaches 100% as against 50- 60% when routine methods are used.
Technology of straight-run naphtha pyrolysis. The pyrolysis process involves cathodically activated distilled water under 15 kgf/cm 2 pressure and at T=120°С. As a result, the output of the main organic synthesis products – ethylene, propylene, bivinyl, benzene almost doubles. For “Nizhnekamskneftekhim”, where the technology was industrially tested, it is equal to putting into operation another “Ethylene” plant.
Technology of electric oil desalting. Before crude oil is transported to a refinery, excessive dissolved salts are removed from it by adding water followed by separation in electrostatic field (ELOU devices). Substituting cathodically activated water for common water makes it possible to accelerate salt extraction process, increase desalting by 3-5 times and reduce added water amount by 2-4 times.
Technology of sugar syrup inversion into glucose-fructose syrup. Sugar syrup of 60-75% concentration is heated, subjected to anodic treatment in RPE-03 reactor, aged at constant temperature and subjected to cathodic treatment in the same reactor. The result is controlled inversion within 5-99%. Sugar saving in confectionary industry and refreshment drink production achieves 20-30%, contributing to health maintenance of people suffering from diabetes.
Technology of printed circuit board and microassembly production. Solutions of chemical agents for metal etching, silicon chemical polishing, chemical and galvanic metallization are prepared using electrochemically activated anolyte and catholyte produced from heavily diluted salts of inorganic electrolytes in de-ionized water. Product quality considerably increases, and there is significant saving of chemical agents (from 10 to 50%), time and power.
Technology of producing potassium-chromia-alumina catalysts of paraffin (butane and isopentane) dehydration using electrochemically activated drinking water increases catalyst's activity and strength by 10%. The technology was developed by specialists of the Syzran plant manufacturing catalysts with the participation of the authors of electrochemical activation technology.
Technology of emulsion polymerization of bivinyl with styrene using electrochemically activated drinking water provides for higher efficiency of bivinyl-styrene rubber production due to reduced consumption of chemicals, such as resin soap (emulsifier), potassium chloride and pyrophosphate; 40% increase in copolymerization rate and improved rubber quality. The technology was developed by researchers and specialists of the Kazan Institute of Chemical Technologies and of the Production Association “NIZHNEKAMSKSHINA” in 1985 with the participation of the authors of electrochemical activation technology.
Technology of non-chemical control of the redox potential and рН of dialyzing solution implemented in BASEX device. Water purified for hemodialysis and containing about 50 mg/l of dissolved salts is subjected to cathodic treatment in a BASEX device. As a result, its redox potential and рН values become such that they secure biocompatibility of dialysis solution produced before supply to dialyzer by feeding concentrated dialysis solution into water purified for hemodialysis. The technology realized in BASEX device makes it possible to reduce hemodialysis procedure duration, bring patient's pressure to normal, completely rule out dermatoses and improve general procedure tolerance.
Technology of hydrogen sulphide removal out of natural gas. The main point of the process lies in absorption of hydrogen sulphide from gas by alkali, generated in diaphragm electrochemical reactor from aqueous solution of sodium sulphate, and further regeneration of absorbent, saturated by hydrogen sulphide, by acid generated in the same electrochemical reactor. Compactness of technological device, high reliability of electrochemical equipment, ability to control selectivity of the process and depth of hydrogen sulphide and mercaptans removal allows to perform efficient oil gas treating, treating of fuel gas going into heat-an d-power economy installations, treating of technological gas emissions (volley and regular) at the chemical, petrochemical industry installations as well as at the special technical equipment and ammunition plants.

All above-indicated technologies are implemented in electrochemical devices featuring specific traits due to their different functional purposes (various technological flow sheets of electrochemical action on water or diluted electrolyte solution, different chemical composition and varying concentration of dissolved substances, different operational modes optimized in accordance with the problem to be solved). Each technology has options, and, consequently, can be implemented with the help of electrochemical devices tailor-made specifically with regard to conditions of operation.


Institute's mission Registration Certification REGISTER Research and Development activities Work structure Specialists and Experts Bibliography ELECTROCHEMICAL ACTIVATION Miscellaneous Scientific-and-technical examination News Contact Data FALSIFICATION	Improvement of known electrochemical systems and technologies Purification, decontamination and conditioning of water in EMERALD devices. There exist electrochemical technologies of drinking water purification in EMERALD devices of different types, their flow charts being quite different due to initial water chemical composition diversity, and to different requirements to quality and chemical composition of purified water. A common feature of all water purification technologies in EMERALD-type devices is that initial water arrives in the electrochemical system consisting of connected in a different order flow-through reactors – electrochemical (FEM), flotation, electro-kinetic, catalytic – where it undergoes consecutive stages of transformation securing removal of heavy metal ion elimination, organic compound oxidation and eradication of all types and species of microorganisms (bacteria, mycobacteria, viruses, fungi, spores), as well as microbial toxins. Technologies of synthesizing electrochemically activated solutions in STEL devices. STEL devices meant for medical purposes are engineering electrochemical systems for producing electrochemically activated washing and antimicrobial solutions – anolyte and catholyte featuring high functional activity and environmental friendliness. Any STEL device contains a flow-through electrochemical diaphragm-type reactor made up of FEM modules, a hydraulic circuit to feed source solution to the reactor and to discharge the products of electrochemical synthesis from the reactor, as well as a power supply source. Besides, STEL devices may be supplied with a system automatically controlling the device's operation parameters, an automated system of periodic rinsing with an acid solution and a number of other gadgets and facilities that determine the degree of STEL device engineering sophistication. There have been developed and launched into commercial production STEL devices with the output of all types of activated solutions (acid and neutral anolyte, alkaline and neutral catholyte) from 10 to 1000 liters per hour. The degree of their technical excellence depends on their ability to produce activated solutions of as low mineralization as possible (permissible sodium chloride content of initial aqueous solution ranging from 0.5 to 5.0 g/l) with the highest possible anolyte oxidants' content and the highest possible catholyte reductive potential value (minus 700 – minus 800 mV relative to silver chloride reference electrode) and its lowest possible mineralization (preferably not exceeding 1.5 g/l). Technology of water decontamination in field conditions in AQUADEZ devices. AQUADEZ devices are based on electrochemical technologies of water decontamination using auxiliary electrolyte in the cathodic chamber of FEM module. That guarantees maximum (up to 20 liters per hour for a single FEM module) output while decontaminating fresh water from surface water sources including bog water with minimum power consumption and under most unfavorable conditions of the devices' operation. There are AQUADEZ devices fitted with reactors the number of FEM-3 modules in which varies from 1 to 12, their output ranging between 10 and 250 liters per hour of decontaminated water at 40 - 500 Wt. Technologies of decontamination and conditioning of swimming-pool water in ALLIGATOR-type devices. Similarity of technologies in this class is determined by the goal and the way to achieve it , i.e., each technology envisages synthesis of antimicrobial components directly from swimming pool water in an electrochemical device using no source chemicals. Also, a common feature of water treatment technologies in ALLIGATOR-type devices is the possibility of gradual elimination of hardness salts from swimming pool water in the process of the device's operation making it soft and agreeable. Technology of oxidant solution production in AQUACHLOR devices. AQUACHLOR devices are intended for producing oxidant mixture solution from an aqueous sodium chloride solution. The devices are manufactured as modules producing 30- 500 g of oxidant mixture per hour. AQUACHLOR devices are based on a new technological process of sodium chloride solution electrolysis – ion-selective electrolysis with diaphragm (ISED), thus combining high cost-effectiveness and complete operational safety in one device. To produce 1 kg of oxidant mixture in terms of molecular chlorine in an AQUACHLOR device, no more than 2.0 kg of sodium chloride dosed into the AQUACHLOR device reactor, in the anodic chambers of compact-size flow-through modular cells under pressure from 0.8 to 1.2 kgf/cm 2 , a humid gaseous oxidant mixture is synthesized, including chlorine (95%), chlorine dioxide (3%), and ozone (2%), which immediately after generation is mixed with water in the ejector mixer of AQUACHLOR device forming oxidant mixture which, unlike common chlorine water or sodium hypochlorite solution, produces no chlorination by-products (trihalomethanes) while interacting with organic compounds in the treated water. AQUACHLOR devices are an alternative compact-size and highly-effective source of oxidant mixture, and can be used instead of cylinders and containers with liquid chlorine and, actually, instead of chlorinators at household and drinking water treatment plants, at local water purification facilities, at household and industrial sewage treatment plants, in swimming pool water purification systems both as single modules, and as a unit of modules connected into a single hydraulic system with specified oxidant output ranging from 30 g per hour to hundreds of kg per hour. Development of new electrochemical systems and technologies Below there are listed some technologies, whose effectiveness has been confirmed in industrial or laboratory conditions, and each of which is an object of investment development. Technology of generating nitrogen and phosphoric fertilizers in irrigation water. The technology is realized by cathodic treatment of irrigation water and introduction into it of very small batches of nitrogenous and phosphoric acid mixture dissolved in anolyte until рН » 7. Large-scale production of nitrogen and phosphoric fertilizers is no longer needed, and consequently there is no need to transport and introduce them into soil. Cropping capacity increases, nitrite and nitrate content in fruits and vegetables is reduced down to its natural level typical for plants growing in ecologically safe environment. Technology of spent lead accumulator renewal. A cathodically activated and heavily diluted sulfuric acid solution is poured into accumulator, and then is brought to desired density by adding concentrated sulfuric acid. Service life of new and worn out accumulators increases by 15- 45%, “charge-discharge” capacity increases by 20- 30%. Technology of uranium and trans-uranium elements' leaching from beds. Reservoir water is subjected to anodic treatment, after which it is mixed with sulfuric acid and is re-injected into the bed. Tenfold economy of sulfuric acid is ensured, and useful leaching product yield increases by 10%. Technology of profound electrochemical treatment of seawater accompanied by producing marketable chemical products: sodium hydroxide solution, hydrochloric acid, sulfuric acid. Seawater undergoes electrochemical treatment by ion-selective diaphragm-type electrolysis, due to which it is divided into sulfuric acid and sodium hydroxide solutions (their concentrations depending on source water mineralization), as well as into gases: chlorine and hydrogen supplied to the reactor for hydrochloric acid production. The technology allows chemical agent production directly on site, for instance, at offshore oil fields and separate drilling platforms) using only electric power and seawater. Power consumption does not exceed 5 kW ? h per 1 kg of chlorine. Technology of precious metals extraction from spent catalysts of motorcar exhaust afterburning. Activated anolyte and catholyte of potable tap water or very weak acid and alkali solutions are used to prepare solutions of agents in the processes of chemical extraction of precious metals (platinum, iridium and rhodium) from spent catalysts. Saving of acids and alkali is above tenfold, and metal yield approaches 100% as against 50- 60% when routine methods are used. Technology of straight-run naphtha pyrolysis. The pyrolysis process involves cathodically activated distilled water under 15 kgf/cm 2 pressure and at T=120°С. As a result, the output of the main organic synthesis products – ethylene, propylene, bivinyl, benzene almost doubles. For “Nizhnekamskneftekhim”, where the technology was industrially tested, it is equal to putting into operation another “Ethylene” plant. Technology of electric oil desalting. Before crude oil is transported to a refinery, excessive dissolved salts are removed from it by adding water followed by separation in electrostatic field (ELOU devices). Substituting cathodically activated water for common water makes it possible to accelerate salt extraction process, increase desalting by 3-5 times and reduce added water amount by 2-4 times. Technology of sugar syrup inversion into glucose-fructose syrup. Sugar syrup of 60-75% concentration is heated, subjected to anodic treatment in RPE-03 reactor, aged at constant temperature and subjected to cathodic treatment in the same reactor. The result is controlled inversion within 5-99%. Sugar saving in confectionary industry and refreshment drink production achieves 20-30%, contributing to health maintenance of people suffering from diabetes. Technology of printed circuit board and microassembly production. Solutions of chemical agents for metal etching, silicon chemical polishing, chemical and galvanic metallization are prepared using electrochemically activated anolyte and catholyte produced from heavily diluted salts of inorganic electrolytes in de-ionized water. Product quality considerably increases, and there is significant saving of chemical agents (from 10 to 50%), time and power. Technology of producing potassium-chromia-alumina catalysts of paraffin (butane and isopentane) dehydration using electrochemically activated drinking water increases catalyst's activity and strength by 10%. The technology was developed by specialists of the Syzran plant manufacturing catalysts with the participation of the authors of electrochemical activation technology. Technology of emulsion polymerization of bivinyl with styrene using electrochemically activated drinking water provides for higher efficiency of bivinyl-styrene rubber production due to reduced consumption of chemicals, such as resin soap (emulsifier), potassium chloride and pyrophosphate; 40% increase in copolymerization rate and improved rubber quality. The technology was developed by researchers and specialists of the Kazan Institute of Chemical Technologies and of the Production Association “NIZHNEKAMSKSHINA” in 1985 with the participation of the authors of electrochemical activation technology. Technology of non-chemical control of the redox potential and рН of dialyzing solution implemented in BASEX device. Water purified for hemodialysis and containing about 50 mg/l of dissolved salts is subjected to cathodic treatment in a BASEX device. As a result, its redox potential and рН values become such that they secure biocompatibility of dialysis solution produced before supply to dialyzer by feeding concentrated dialysis solution into water purified for hemodialysis. The technology realized in BASEX device makes it possible to reduce hemodialysis procedure duration, bring patient's pressure to normal, completely rule out dermatoses and improve general procedure tolerance. Technology of hydrogen sulphide removal out of natural gas. The main point of the process lies in absorption of hydrogen sulphide from gas by alkali, generated in diaphragm electrochemical reactor from aqueous solution of sodium sulphate, and further regeneration of absorbent, saturated by hydrogen sulphide, by acid generated in the same electrochemical reactor. Compactness of technological device, high reliability of electrochemical equipment, ability to control selectivity of the process and depth of hydrogen sulphide and mercaptans removal allows to perform efficient oil gas treating, treating of fuel gas going into heat-an d-power economy installations, treating of technological gas emissions (volley and regular) at the chemical, petrochemical industry installations as well as at the special technical equipment and ammunition plants. All above-indicated technologies are implemented in electrochemical devices featuring specific traits due to their different functional purposes (various technological flow sheets of electrochemical action on water or diluted electrolyte solution, different chemical composition and varying concentration of dissolved substances, different operational modes optimized in accordance with the problem to be solved). Each technology has options, and, consequently, can be implemented with the help of electrochemical devices tailor-made specifically with regard to conditions of operation.
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