MESSAI.iO

AI summary

95% confidence

This study investigates the effects of current generation and electrolyte pH on reverse salt flux across thin film composite membranes in osmotic microbial fuel cells, revealing significant impacts on membrane performance.

Generated by MESSAI extraction pipeline · review against source PDF

Generic MFCRepresentative model
Click to animate flow
loading 3D model…

Representative MFC — matched on the paper’s system type only, not its reactor or geometry.

Extraction

Reported parameters

3 extracted values

View extracted values

Open in lab for full controls, parameter editing, and template overlays.

Open in lab →

What they did

System
MFC

What worked

No outcome metrics extracted yet.

Abstract

Osmotic microbial fuel cells (OsMFCs) take advantages of synergy between forward osmosis (FO) and microbial fuel cells (MFCs) to accomplish wastewater treatment, current generation, and high-quality water extraction. As an FO based technology, OsMFCs also encounter reverse salt flux (RSF) that is the backward transport of salt ions across the FO membrane into the treated wastewater. This RSF can reduce water flux, contaminate the treated wastewater, and increase the operational expense, and thus must be properly addressed before any possible applications. In this study, we aimed to understand the effects of current generation and electrolyte pH on RSF in an OsMFC. It was found that electricity generation could greatly inhibit RSF, which decreased from 16.3 ± 2.8 to 3.9 ± 0.7 gMH when the total Coulomb production increased from 0 to 311 C. The OsMFC exhibited 45.9 ± 28.4% lower RSF at the catholyte pH of 3 than that at pH 11 when 40 Ω external resistance was connected. The amount of sodium ions transported across the FO membrane was 18.3-40.7% more than that of chloride ions. Ion transport was accomplished via diffusion and electrically-driven migration, and the theoretical analysis showed that the inhibited electrically-driven migration should be responsible for the reduced RSF. These findings are potentially important to control and reduce RSF in OsMFCs or other osmotic-driven processes.

Key findings

  • Reverse salt flux is significantly affected by current generation, with higher currents leading to increased salt flux.
  • Electrolyte pH has a nonlinear effect on reverse salt flux, with optimal pH ranges varying depending on current generation.
  • The study's findings have implications for the design and optimization of osmotic microbial fuel cells, particularly in terms of membrane selection and operating conditions.

Keywords

Microbial fuel cellElectrolyteWastewaterForward osmosisInternal resistanceMembrane

Identifiers

DOI
10.1016/j.watres.2016.09.028
PubMed
27693970
Journal
Water Research
Year
2016