Effect of the incorporation of reducibility promoters (Cu, Ce, Ag) in Co/CaSBA-15 catalysts for acetic acid steam reforming

In this work, we have faced the problem associated with the addition of Ca to Co/SBA-15, which gave rise to an increase in the dispersion of the particles at the expense of increasing its reduction temperature, thus limiting its reducibility as demonstrated by XPS. This detrimental effect has been solved by the inclusion of reducibility promoters such as Cu, Ag and Ce. All these promoters led to an increase in the acetic acid conversion attributed to their beneficial effect in the catalyst reducibility. With the inclusion of Ce to Co/CaSBA-15, the high dispersion was maintained while the percentage of reduced Co species increased by similar to 90% compared with Co/CaSBA-15, leading to the best catalytic performance (X similar to 99%, Y-H2= 71.8%) after 5 hours TOS in the acetic acid steam reforming (S/C= 2) at 600 degrees C using aWHSV= 30.1 hours(-1). Furthermore, Co-Ce/CaSBA-15 showed good stability with hydrogen yield close to the thermodynamic value. These results highlight the necessity of combining both dispersing additives and promoters of reducibility to enhance the catalytic performance in steam reforming.