Korea’s first development of water electrolysis technology to produce hydrogen from discarded water

A research team led by Dr Joo-Chan Yang and Dr. Seung-Mok Choi of the Green Hydrogen Materials Laboratory of the Korea Institute of Materials Science (hereinafter referred to as the Institute of Materials Science), a government-funded research institute under the Ministry of Science and ICT, developed a non-precious metal catalyst/performance electrode material high and applied to waste alkali water electrolysis system Successfully developed Korea’s first waste alkali anion exchange membrane water electrolysis technology based on

Anion exchange membrane water electrolysis is an ideal technology that combines the advantages of using non-noble metal electrodes of conventional alkaline water electrolysis technology with the ease of operation and simplicity of cation exchange membrane water electrolysis technology. It can be said to be a next generation water electrolysis system that can obtain high purity hydrogen along with better economic feasibility in terms of green hydrogen production.

Research on water electrolysis, a green hydrogen production method, has been using purified water electrolytes until now. An average of 9 tonnes of purified water is required to produce 1 tonne of hydrogen through water electrolysis. To get 9 tonnes of purified water, about twice as much water is needed. As such, the production of green hydrogen requires a large amount of water in addition to the electricity required for electrolysis, so the cost associated with the water used is also an important factor in determining competitiveness price.

Waste alkali is defined as strongly alkaline waste with a pH of 12.5 or higher, and emissions are increasing every year due to the increasing demand for semiconductors and the development of the electronics industry. The research team applied the key source materials and components of water electrolysis, which uses waste alkali directly as an electrolyte, to a unit cell that simulates a commercial system.

First of all, in order to ensure the activity and durability of non-noble metal catalysts at the same time, a composite catalyst was developed with a high conductivity carbon layer uniformly coated on the surface of the catalyst. The catalyst showed high uniformity even in the electrodeization process, and exhibited about 2.8 times better activity and high durability compared to conventional electrodes in the evaluation of anion exchange water membrane cells electrolysis unit.

The research team applied this technology to a waste alkali electrolysis water electrolysis unit cell to achieve a high current density of 1,420 mA/cm2 (non-precious metal application, 2V standard), and showed better durability even at a current density that can. production of hydrogen smoothly confirmed that Consequently, by analyzing metal ions present in waste alkali, it was revealed that the increased electrolyte ion conductivity improves the performance of water electrolysis.

Senior researcher Choi Seung-mok (Head of the Green Hydrogen Materials Research Division), who is in charge of the project, said, “If this technology is commercialized, it can be immediately used in the water electrolysis system that based on existing alkali. , enable mass production and access to the hydrogen production market.”

This research achievement was supported by the Ministry of Science and ICT, and was supported by the Korea Materials Research Institute’s main project ‘Development of high durability electrodes and evaluation technology for HMI water electrolysis for green hydrogen production’ and ‘2.5 for hydrogen production ‘, the Ministry of Trade, Industry and Energy’s material parts technology development project It was carried out by ‘developing high-performance catalyst electrodes for the electrolysis of kW-class waste alkali HMI water and component technology’.

In addition, the research results were published in ‘Journal of Materials Chemistry A (IF=14.511, 1st author: Doctoral course researcher Jeong Jae-yeop, Dr. Park Yoo-se (currently a professor at Chungbuk National University)’ , which is an internationally renowned journal in the field of materials energy) on November 10 published by date.

Currently, the research team is conducting follow-up research for the application and commercialization of the waste alkali water electrolysis stack system through large area uniform electrodes.