Optimization of methanol steam reforming over a Au/CuO–CeO2 catalyst by statistically designed experiments

The catalytic performance for steam reforming of methanol over 5 wt.% Au/CuO–CeO2 catalysts prepared by deposition–precipitation was investigated using a statistical set of experiments in order to optimize the methanol conversion with minimal carbon monoxide (CO) selectivity. The operating temperature, steam to methanol (S/M) ratio, liquid feed rate and the catalyst weight to He flow rate (W/F) ratio, were evaluated with a full 24 factorial design experimental matrix with four central points. The liquid feed rate displayed a much greater influence on the response, masking the importance of the other factors. At a fixed low liquid feed rate, only the operating temperature had a significant influence on the methanol conversion, whilst this plus the S/M ratio and their interaction influenced the CO selectivity. A central composite rotatable design was then used to approximate the optimal conditions by simultaneously considering the methanol conversion and CO selectivity. The optimum theoretical conditions were found to lie within an operating temperature of ~ 295 °C to ~ 307 °C and an S/M ratio of ~ 1.82 to 2.00 (at a liquid feed rate of 1 cm3 h− 1 and a W/F ratio of 0.17 g s cm− 3), in close agreement with the experimental results.

Graphical abstractRegion (in the shade portion) of the maximal methanol conversion () with the minimal CO selectivity () for SRM over 5 wt.% Au/CuO–CeO2 catalyst.Figure optionsDownload full-size imageDownload as PowerPoint slideFigure optionsDownload full-size imageDownload as PowerPoint slideFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► 5 wt.% Au/CuO–CeO2 catalyst for steam reforming of methanol (SRM). ► A full 24 factorial design experimental matrix with four central points. ► The liquid feed rate masked the importance of the other factors. ► A central composite rotatable design within the response surface method. ► Complete methanol conversion with a minimal CO selectivity.