Computational Fluid Dynamics Modelling of Photoelectrocatalytic Reactors for the Degradation of Formic Acid

Abstract:

In this study, computational fluid dynamics (CFD) simulation was used to predict the performance of photoelectrocatalytic (PEC) reactors with surface reactions. PEC process is a promising and sustainable method that is capable for simultaneous organic degradation and hydrogen production. However, the overall PEC process efficiency is still unsatisfactory and not ready for scale-up application. Preliminary study using CFD model can help to reduce development time, money and effort in experimental work while providing comprehensive analysis and optimum PEC reactor design prior to its real physical fabrication. CFD model integrates irradiance distribution, hydrodynamics, species mass transport and chemical reaction kinetics within the reactor. The performance of PEC reactor for organic degradation depends on reactor configurations and hydrodynamic conditions. Thus, the main aim of this study was to optimize different PEC reactor designs using CFD modelling by varying the reactor configurations and hydrodynamic flow conditions for improved efficiency in degrading the sample organic pollutant of formic acid. The CFD modelling showed higher formic acid degradation efficiency for the simulated convex surface photoreactor than the flat surface photoreactor due to the former possess the ability to concentrate the absorbed light onto the photoanode surface. Besides, the CFD modelling showed that the formic acid degradation rate increased with decreasing inlet fluid flow velocity. This was due to the uniform flow distribution that enables evenly coverage of photoanode surface for subsequent degradation of formic acid in the PEC reactors. Further experimental work is required to validate the CFD simulation to allow better understanding and improvement of the overall efficiency of PEC reactors.

• Periodical: Applied Mechanics and Materials (Volume 835)
• Pages: 386-393
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.835.386
• Online since: May 2016
• Authors: Yi Wen Phuan, Eileen Ai Lyn Lau, Harun Mohamed Ismail, Byeong Kyu Lee, Meng Nan Chong*
• Keywords: Computational Fluid Dynamics (CFD), Hydrogen Production, Organic Degradation, Photoelectrocatalytic (PEC), Reactor Modelling

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