Hokkaido University Research Profiles

Japanese
Environment

Catalytic Purification of Nitrate-nitrogen Contaminated Water

High-performance catalyst for reductive decomposition of nitrate-nitrogen

Groundwater pollution with nitrate-nitrogen has become a problem. We have developed a high-performance solid catalyst that promotes decomposition of nitrate-nitrogen in water into nitrogen gas through a reaction with hydrogen gas at room temperature. Using a purification system incorporating this catalyst, we have succeeded in purifying contaminated groundwater.

Content of research

Groundwater pollution with nitrate-nitrogen has become a nationwide problem. We have developed a high-performance solid catalyst that promotes decomposition of nitrate-nitrogen in groundwater into nitrogen gas, and have also succeeded in purifying actual contaminated groundwater using a purification system incorporating the developed catalyst.
The treatment of water containing nitrate-nitrogen is predominantly a biological treatment that involves anaerobic and aerobic treatment. The equipment for that is generally large and its operation is complicated. The catalytic water purification system we have developed is very compact and does not require complicated operations, making it possible to purify contaminated water simply by passing hydrogen gas and contaminated water through a temperature-controlled reactor filled with catalyst.

  • Process image of the catalytic method
    We have developed a high-performance catalyst consisting of tin-palladium alloy particles immobilized on activated carbon.

  • Purification of contaminated groundwater using purification equipment

Potential for social implementation

  • ・Purification of nitrate-nitrogen-containing water (tap water and wastewater) in small-scale facilities where biological treatment is difficult
  • ・Wastewater treatment for hydroponics facilities and plant factories

Appealing points to industry and local governments

We are also examining catalytic decomposition and adsorption removal of ammonia nitrogen.
We request your support to find users and investigate untapped applications.

Intellectual property related to this research

特許第4759731号 「撥水性を有する貴金属含有触媒」
2022/5/27Released