Steam Reforming of Model Bio-Oil Aqueous Fraction Using Ni-(Cu, Co, Cr)/SBA-15 Catalysts

Abstract

Hydrogen obtained from biomass derivatives is considered a promising alternative to fossil fuels. The aim of this work is to test the viability of Ni-M/SBA-15 (M: Co, Cu, Cr) catalysts for the hydrogen production from bio-oil aqueous fraction reforming. Tests were performed in a fixed-bed reactor at 600 °C and atmospheric pressure. Firstly, the steam reforming (SR) of acetic acid, hydroxyacetone, furfural and phenol, as representative constituents of the bio-oil aqueous fraction, was carried out. Lower reactivity with increasing carbon number and decreasing steam-to-carbon ratio was observed. Coking rate during SR is a consequence of carbon number and aromaticity of the reactant, as well as the steam-to-carbon ratio. However, deactivation also depends on the graphitization degree of carbon filaments, higher in the case of coke formed from phenol. Then, the performance of the Ni-M/SBA-15 catalysts was studied in the reforming of a bio-oil aqueous fraction surrogate containing the four model compounds. Ni-Co/SBA-15 and Ni-Cr/SBA-15 samples were the most active because Co also catalyze the steam reforming reactions and Cr promotes the formation of very small Ni crystallites accounting for high conversion and the low coke deposition (~8 times lower than Ni/SBA-15) in the form of poorly condensed carbon filaments.

Coke formation and deactivation during catalytic reforming of biomass and waste pyrolysis products: A review

“…At the catalyst level, many attempts have been performed to control the deposition of coke in these reactions or minimize its impact. Changing the morphology of the metal (Ni) has recurrently been used to control catalyst deactivation, either by decreasing the particle size [254,255], changing the chemical environment of Ni [256], using a different synthetic pathway [257], using different calcination/reduction methods [144], or using other metals such as the incorporation of Co [258,259], the use of Fe-Zn [260] or other metals all together [261]. On the other side, several attempts have been made to control the catalyst deactivation trough support modification, either by changing porosity or metal placement on the support [28], or by using other conventional supports such as ZrO2, SiO2, MgO, TiO2 [262] or unconventional ones [263].…”

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

“…On the other hand, it was verified that addition of certain promoters to SBA-15 based catalysts considerably dropped the reduction temperature. 17,38 Other authors had also reported a decrease in the reduction temperature by the addition of different promoters to the initial catalyst. 39,40 Thus, the aim of this work is to deeply analyse the effect of Ca addition to Co/SBA-15 to be used in acetic acid steam reforming.…”

“…16 According to literature, many papers can be found using bio-oil model compounds because of its complex composition. 1,5,[17][18][19][20] In this context, carboxylic acids are the main component of bio-oil, such as acetic acid which is usually in high concentration, thus being frequently used as representative compound. 18,[21][22][23] In steam reforming reactions, other nondesired reactions can also take place.…”

“…The most important might be carbon deposition, which can deactivate the catalyst decreasing its activity towards hydrogen production. 4,17 As a result, catalyst plays an important role in steam reforming reactions and it will determine the hydrogen production efficiency from the feedstock selected. [24][25][26][27][28] Noble metal based-catalysts had demonstrated high activity and hydrogen selectivity.…”

Ordinary clay as a support of nickel catalyst for steam reforming of acetic acid: Impacts of pretreatments of clay on catalytic behaviors

“…26 Carriers generally account for a significant portion of the cost in manufacturing a catalyst. Many reforming catalysts employed the artificially synthesized carriers such as SBA-15, 27,28 KIT-6, 29 and alumina 30,31 with complex synthesis steps, which is not conducive to industrial application as the use these carriers would increase the process cost.…”