Valorization of alcoholic wastes from the vinery industry to produce H2

Abstract

[EN] This paper focuses on the development of active and stable catalysts for the steam reforming of alcoholic wastes. Two catalysts with high activity in the steam reforming of ethanol have been studied in the steam reforming of an alcoholic waste from the vinery industry, as previous step to their industrial scale up. The catalysts are based on cobalt supported on Zn-hydrotalcite-derived material and natural sepiolite. At laboratory level, the catalytic material based on natural sepiolite showed the best catalytic performance maintaining its catalytic activity for more than 160 h in presence of 50 ppm of sulfur contained in the alcoholic waste. Thus, sepiolite based catalyst was scaled up to prepare a first generation of catalytic monoliths. The reforming activity of this first generation of monoliths was found lower than their corresponding powdered catalyst. The high calcination temperature (1573 K) used in the manufacture of the first generation of monoliths was the responsible of their low performance, which was related to the sintering of cobalt catalyst in a larger crystallite size of metallic cobalt. A second generation of monoliths was prepared using a lower calcination temperature (873 K). Now, the monoliths exhibited a high catalytic performance, similar to the powdered catalyst. The excellent results obtained with the second generation of monoliths have been protected under an invention patent (E201731077). This is the first time that catalytic monoliths based on natural sepiolite promoted with Co are successfully manufactured and tested in the steam reforming of alcoholic wastes from the distillery industry to produce hydrogen.