Conventional wastewater treatment facilities face significant challenges such as high carbon emissions and energy consumption. Our research team developed a low-carbon-emission photoelectrochemical (PEC) system for the treatment of saline wastewater, coupled with green hydrogen (H2) generation. The PEC system demonstrates exceptional performance in treating saline sewage, effectively meeting Hong Kong discharge standards for chemical oxygen demand (COD), ammonia-N, and E. coli within 40 minutes at 2 V (vs. Ag/AgCl) when treating simulated saline sewage. When applied to real saline sewage (sampled from Stonecutters Island Sewage Treatment Works in Hong Kong), which has a more complex composition and higher turbidity, the PEC system still meets the discharge standards within 2 hours of PEC treatment. Additionally, we demonstrate the scalability of the PEC system from batch to a large-scale continuous flow reactor, and it can generate 18.13 mol/m3 of green H2 (equivalent to 0.92 kWh/m3 of electricity). This innovative technology results in significant reductions of 98% in scope 1 emissions (direct GHG emissions) and 97% in total carbon emissions compared to conventional wastewater treatment plants, illustrating its excellent environmental benefits and enormous practical potential.
Professor Irene Lo has been teaching at HKUST since 1992, and she is currently a Chair Professor in the Department of Civil and Environmental Engineering. She was appointed by HKSAR Government as Justices of the Peace (JP) in 2017. Professor Lo is an internationally renowned scholar and is among the first to invent iron-based nanomaterials and photocatalytic materials for pollution control. She was the recipient of numerous prestigious international research awards and university distinguished teaching awards. She has been invited to give over 100 plenary/keynote/invited speeches at many international and regional conferences in Asia, Europe, Africa, and North America.
Clean water and clean air are vital for public health. This project focuses on developing high-efficiency and environmentally sustainable filters for removing harmful air/water pollutants. The team has developed novel architectures and functionalities for the filters to achieve high permeance, high removal efficiency, and excellent reusability.
