| Title |
Human urine electrolysis for simultaneous green hydrogen and liquid fertilizer production for a circular economy: A proof of concept |
| ID_Doc |
28259 |
| Authors |
Im, K; Park, M; Kabir, MM; Sohn, W; Choo, Y; Shon, HK; Nam, SY |
| Title |
Human urine electrolysis for simultaneous green hydrogen and liquid fertilizer production for a circular economy: A proof of concept |
| Year |
2024 |
| Published |
|
| DOI |
10.1016/j.desal.2023.117059 |
| Abstract |
This study explores a novel process for hydrogen production and urine concentration using water electrolysis, employing a hydrophobic membrane and hydrogel electrolyte. The process utilizes a hydrophobic membrane to provide pure water from human urine, while simultaneously producing hydrogen through electrolysis, and concentrating urine for liquid fertilizer production. A suitable hydrogel electrolyte was developed, with polyvinyl alcohol (PVA)-based hydrogels and varying potassium hydroxide (KOH) concentration, showing efficient ion conductivity. The PVA-KOH 30 wt % hydrogel incorporating melamine exhibited promising performance in cell testing, achieving a current density of 204.35 mA/cm2 at 2 V. Long-term electrolysis tests indicated sustained efficiency, although a decline in current density during 96 h was attributed to hydrophobic membrane fouling. Nonetheless, the hydrogel electrolyte demonstrated minimal fouling, successfully concentrating the urine about 5 times. This concentrated urine serves as liquid fertilizer, while the produced hydrogen acts as an energy source, and the oxygen can be recycled for use in a membrane bioreactor (MBR), establishing a sustainable energy cycle system. |
| Author Keywords |
Water electrolysis; PVA-KOH hydrogel; Hydrophobic membrane; Resource recovery; Hydrogen production; Circular economy |
| Index Keywords |
Index Keywords |
| Document Type |
Other |
| Open Access |
Open Access |
| Source |
Science Citation Index Expanded (SCI-EXPANDED) |
| EID |
WOS:001096313400001 |
| WoS Category |
Engineering, Chemical; Water Resources |
| Research Area |
Engineering; Water Resources |
| PDF |
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