This study focuses on developing a mathematical model for the electrochemical reduction of CO2 into CH3OH in a microfluidic flow cell. The present work is the first attempt to model the electro-reduction of CO2 to alcohols, which is a step forward towards the scale up of the process to industrial operation. The model features a simple geometry of a filter press cell in which the steady state isothermal reduction takes place. All significant physical phenomena occurring inside the cell are taken into account, including mass and charge balances and transport, fluid flow and electrode kinetics. The model is validated and fitted against experimental data and shows an average error of 20.2%. The model quantitatively demonstrated the dominance of the) (2 L CO c Concentration of CO2 in the liquid bulk, mol/m 3 cG Gas solubility in salt solution, mol/l cGo Gas solubility in water, mol/l CO Oxidized species concentration expression CR Reduced species concentration expression Di Diffusion coefficient of species i, m 2 /s Eeq Equilibrium potential of half-cell reaction, V F Faraday's constant FE Faradaic efficiency

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This study uses confocal microscopy and image processing to investigate the microstructural changes of coating–metal systems immersed in a heated acidic bath. Unlike standard optical microscopy techniques, 3D confocal microscopy images can quantitatively reveal microscopic defects formed at early stages of cathodic delamination. The coatings are made of fluorescent epoxy–phenolic resins cured at high temperatures onto tinplate (T23) and tin-free steel (TFS) substrates. When the coated metal substrates are immersed in acetic acid, a series of microscopic corrosion events occur at the polymer–metal interface. These events are quantified by changes in the thickness distribution of the degraded samples relative to that of intact coatings. The degradation rate is highest for epoxy–phenolic polymers on TFS substrates, represented by multiple orders of magnitude increase in the number density of defect sites. Higher molecular weight coatings provide slightly better resistance against delamination. The coating thickness dictates the rate of oxygen diffusion and ion transport along the polymer–coating interface, where raised asperities serve as localized sites for metal oxidation and formation of alkaline species, leading to subsequent delamination of the cured polymers from the surfaces. The results show that the metal surface topology is as important as chemistry when designing the corrosion resistance of products containing acidic liquids, and that confocal microscopy is useful in quality control through early detection of mesoscale polymer failure.

We seek to reveal the corrosion protection mechanisms of intact thermosetting epoxy coatings on metal substrates as a prerequisite for the future design of innocuous alternatives to bisphenol A-based epoxy...