Hydrogen production from industrial wastewaters: An integrated reverse electrodialysis - Water electrolysis energy system. (1st December 2018)

• Record Type: Journal Article
• Authors: Tufa, Ramato Ashu; Hnát, Jaromír; Němeček, Michal; Kodým, Roman; Curcio, Efrem; Bouzek, Karel
• Is Part Of: Journal of cleaner production. Volume 203(2018)
• Page Start: 418
• Page End: 426
• Publication Date: 2018-12-01
• Subjects: Industrial wastewater -- Reverse electrodialysis -- Salinity gradient power -- Water electrolysis -- Hydrogen production; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2018.08.269
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: This work presents a novel approach combining reverse electrodialysis (RED) and alkaline polymer electrolyte water electrolysis (APWEL) for renewable hydrogen production. APWEL is fuelled by salinity gradient power (SGP) extracted from sulfate (SO4 2− )-rich industrial wastewater. The performance of a pilot-scale RED unit (200 cells, active area: 31.5 × 63.5 cm 2 ), using salt solutions mimicking sulfate-rich waste streams (0.01–0.3 M Na2 SO4 ), was evaluated. An open circuit voltage (OCV) of 12.3 V, a maximum power density of 0.22 W/m 2 MP (MP: membrane pair) and internal area resistance of 43.2 Ωcm 2 /cell were recorded by using 0.01 M/0.3 M Na2 SO4 solutions at 35 °C. The APWEL stack (6 cells, active area: 5 × 5 cm 2 ), equipped with Ni foam electrodes and heterogeneous anion-selective membranes, was tested with varying concentrations of liquid electrolyte (0.85–2.5 M KOH) and varying temperatures (28–48 °C). The APWEL stack attained a maximum current density of 110 mA/m 2 at 1.85 V/cell (i.e. 11 V per stack), 2.5 M KOH and 48 °C. Under these conditions, the integrated system exhibited a maximum hydrogen production rate of 50 cm 3 /h·cm 2 . This study opens up a new perspective on renewable hydrogen production fuelled by non-intermittent SGP from SO4 2- -rich industrial effluents. Graphical abstract: Image 1 Highlights: Integrated RED-APWEL system for renewable hydrogen production using wastewaters. Clean energy from SO4 2- -rich industrial wastewaters by RED as a new perspective. RED with SO4 2- -rich wastewater attained maximum power density of 0.22 W/m 2 MP. Optimized APWEL unit for high efficiency in hydrogen production. The integrated system exhibited a maximum hydrogen production rate of 50 cm 3 /h·cm 2 .