# Application of mixed metal oxide anode for the electro-oxidation/disinfection of synthetic urine: Potential of harnessing molecular hydrogen generation.
> 混合金属酸化物アノードを用いた合成尿の電気酸化・消毒と分子状水素生成の可能性


## Abstract

This study examined the performance of mixed metal oxide anodes in the electro-oxidation and disinfection of synthetic urine, while simultaneously evaluating the feasibility of recovering molecular hydrogen gas as a commercially valuable byproduct. Operational parameters including pH, current density, treatment duration, and N/Cl ratio were systematically assessed using response surface methodology. Under optimized batch conditions, COD and TOC reductions of 87.25% and 85.88% were achieved within 8.8 hours, respectively. Complete inactivation of E. coli-spiked wastewater was accomplished in 45 minutes. Incorporating photo-electrocatalysis reduced the required processing time to 6 hours. The anode material demonstrated durability over 100 reuse cycles (207.5 hours total). Intermediate compounds generated during the process were characterized by LC-MS analysis. A techno-economic assessment under optimized conditions estimated the cost at 0.85 USD per kilogram of COD removed.

### Mechanism

Electro-oxidation at mixed metal oxide anodes drives oxidative degradation of organic compounds in synthetic urine, while the cathodic half-reaction generates molecular hydrogen gas as a byproduct; photo-electrocatalysis further accelerates the overall oxidation process.

## Bibliographic

- **Authors**: Singla J, Sangal VK, Singh A, Verma A
- **Journal**: J Environ Manage
- **Year**: 2020 (2020-02-01)
- **PMID**: [31783214](https://pubmed.ncbi.nlm.nih.gov/31783214/)
- **DOI**: [10.1016/j.jenvman.2019.109847](https://doi.org/10.1016/j.jenvman.2019.109847)
- **Study type**: other
- **Delivery route**: not specified
- **Effect reported**: not assessed

## Delivery context

The delivery route is not clearly identifiable from this paper. For hydrogen intake, inhalation is the most efficient route; inhalation, however, carries explosion risk (empirical LFL of 10%; high-concentration devices are not recommended).

## Safety notes

The delivery route is not clearly identifiable from this paper. For hydrogen intake, inhalation is the most efficient route; inhalation, however, carries explosion risk (empirical LFL of 10%; high-concentration devices are not recommended).

See also:
- [Inhalation concentration and LFL / UFL](https://h2-papers.org/en/safety-notes/inhalation-concentration)
- [Consumer Affairs Agency accident cases](https://h2-papers.org/en/safety-notes/accident-cases)

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> **Cite as**: H2 Papers — PMID 31783214. https://h2-papers.org/en/papers/31783214
> **Source**: PubMed PMID [31783214](https://pubmed.ncbi.nlm.nih.gov/31783214/)