Fuel Processing Technology, Vol.96, 160-168, 2012
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 similar to 295 degrees C to similar to 307 degrees C and an S/M ratio of similar to 1.82 to 2.00 (at a liquid feed rate of 1 cm(3) h(-1) a W/F ratio of 0.17 g s cm(-3)), in close agreement with the experimental results. (C) 2011 Elsevier B.V. All rights reserved.