Electrodes and electrolytic cells in modern society

~Helping to build a clean global environment through electrochemistry~

Among the changes in industrial electrolysis technology, great effort has been spent on improving and developing electrolytic cell components in order of transition from conventional processes or realization of new electrolytic processes. We can see that new processes and materials have repeatedly been developed through synergistic methods, to respond to social demand for environmental feasibility and energy saving. In some cases, new electrode materials have played a core role in this development process, one of these being DSE® electrode.

Energy-saving and environmental technologies:

The soda industry is one of the base material industries in which salt is used as a raw material to manufacture chemicals to be used for raw materials, auxiliary materials, and reagents in a wide range of industrial fields. In Japan, the focus is on electrolytic chlor-alkali industry in which brine is electrolyzed to manufacture caustic soda, chlorine, and hydrogen. The ion exchange membrane process is used in all of the domestic chlor-alkali production, except soda ash industry. Approximately 3.500kWh of electric power was used for production of 1 ton of NaOH in the age of mercury process in 1970s, but this electric power basic unit has now been reduced to 2,400kWh or less. The reduction amount of electric power generated in Japan is 4.4 TWh/year, which corresponds to CO2 reduction when 3% of Japan's forest area is converted into forests for the sake of contribution to environment. Among this, the reduction amount of electric power due to transition from the conventional graphite electrodes to DSE® electrode is 1.4 TWh/year, which is equivalent to CO2 absorption by 1% of Japan's forest area (about as large as Kanagawa Prefecture). This astounding reduction of the environmental burden in key industries has been achieved through technological innovation. Even now, there is ongoing development for improving hydrogen evolving electrodes, as well as research development on oxygen gas-diffusion-electrode cells, which is an innovative next-generation technology. These efforts aim to further improve the power consumption rate under higher current density.

Printed circuit boards (PCB) are integrated into the electric/electronic equipment we can generally see in our day-to-day lives. These printed circuit boards are made of copper-clad laminates in which copper foils and resin films are laminated, and conductor circuits are formed on their surface by removing the unnecessary areas of copper foil. Copper functions as a circuit conductor in this case. In the electrolytic copper foil industry, which is one of the industries involved in copper foil production, an oxygen evolving electrode is used as a counter electrode. The conventional lead-based electrodes have flaws such as electrolyte pollution and product contamination resulting from their consumption, causing concern over serious environmental pollution. Transition from the lead-based electrodes to DSE® electrode contributes to improvement of the environment and reduction of the electric power basic unit.
Even other electrolysis processes such as zinc electroplated steel sheet , aluminum electrolytic capacitor processing, metal electrowinning, and PCB plating, are yielding similar effects.

Meanwhile, an electrolytic apparatus with small environmental load plays an important role in cleaning processes that enable microfabrication in the processes of manufacturing electronic components, semi-conductors, liquid crystal, etc. Ozone gas/ozone water, hydrogen gas/hydrogen water, NF3 gas, etc. are manufactured through electrolysis. These have realized substitution of the existing cleaning solutions prepared from high-purity and concentration chemicals.

In addition to those mentioned above, the electrolysis technologies have been highly utilized as core technologies in corrosion engineering, water treatment (e.g., ozone water treatment, seawater treatment, and electrolytic floatation), recycling processes, and so forth at a place not viewed.

Technologies for stable energy supply:

Reduction of carbon dioxide emissions is a main challenge in suppressing global warming. Under the international guidelines for transition from fossil fuels to other types of energy, and considering the current situation where anxiety about nuclear energy is not being dispelled, introduction of renewable energy such as solar power and wind power has been promoted under the name of liberalization and diversification of electric power generation, and "energy mix".
Since this natural energy fluctuates wildly depending on weather conditions, a large-scale rechargeable battery is used as one method for reducing these fluctuations. However, the capacity of the rechargeable battery is insufficient to cope with variation of weather on a global scale and seasonal fluctuations. In the first place, the power loss cannot be ignored in long-term power transmission of electricity. Thus, development of technologies to convert electrical energy to stable chemical substances (energy carriers) for storage and transportation of the electrical energy. Hydrogen is the top candidate as the carrier. Fuel cell vehicles and fuel cell cogeneration systems are the leading technologies.
Water electrolysis technology (including high-performance electrodes and construction of cells) with large scale of a mega-watt class for manufacturing hydrogen from water can realized the stable supply of energy, and therefore is positioned as an important and unavoidable development theme towards the realization of a hydrogenated society.

Technologies relating to living environments:

In our everyday lives, we use many types of functional water generated mainly through electrolysis, for example alkaline ionized water, hypochlorous acid, ozone water, and hydrogen water, which promote our healthy and hygienic lifestyles. The alkaline ionized water has long been known to have an effect of improving gastrointestinal symptoms. In Japan, electrolyzed water generators for household use were approved as controlled medical devices in 2005. Electrolyzed water containing hypochlorous acid was approved as a specified food additive in 2002 in Japan, and application of the electrolyzed water containing hypochlorous acid water to disinfection devices in various fields is progressing. Recently, this electrolyzed water is approved as an agricultural specific material. Ozone has also been utilized as an existing food additive for a long time, and contributes to food production, hygienic environments, and medical fields utilized in a gas form or a liquid form. The effects of hydrogen on living organisms have recently been discovered, and treatment techniques using the effects thereof have been studied extensively.
Special feature of the electrolytic processes are that effective substances can be quickly generated and utilized at any time if raw materials and electric power are available, and that, time and effort for storing substances that are difficult to preserve can be saved. Recognition that the electrolytic apparatuses are safety has been spreading in our lives. However, because the electrolytic apparatuses are the familiar tools, it is necessary to understand effects and efficacy of each of functional water, and develop the electrolytic apparatuses that ensure dosage and usage of the functional water.

As described above, electrolysis apparatuses comprising electrodes and electrolytic cells contribute significantly to industries and daily lives in modern society. We hope that safe and economical electrolytic products are constantly provided, as well as revolutionary electrolytic processes will be realized as a result of a fusion of new materials including electrodes and new processes based on superior structural design and operational technologies.