# Exploring CeO\({}_{2}\)-Doped Co/SBA-15 Catalysts for Acetic Acid Oxidative Steam Reforming
## 1 Introduction
[30] investigated the ethanol oxidative steam reforming reaction using Ni and Pt-Ni catalysts supported on CeO\({}_{2}\)-SiO\({}_{2}\), achieving complete ethanol conversions and hydrogen yields close to thermodynamic equilibrium at temperatures above 450 \({}^{\circ}\)C. These works underscore the potential of CeO\({}_{2}\)-SiO\({}_{2}\) supports, highlighting that the incorporation of CeO\({}_{2}\) into the SiO\({}_{2}\) matrix enhances oxygen mobility and strengthens metal-support interactions. This promotes the dispersion of the active phase and, likewise, improves the catalytic stability. The current employment of mesostructured SiO\({}_{2}\), such as SBA-15, enhances these structural and catalytic advantages. Several studies had explored CeO\({}_{2}\)-doped SBA-15 in the steam reforming of ethanol [31], methanol [32], propylene glycol [33], glycerol [34], and toluene [35], thus providing evidence of its viability for hydrogen production from oxygenated compounds. This raises potential applications in the upgrading of the aqueous phase of bio-oil, focusing on acetic acid conversion by reforming reactions. Acetic acid oxidative steam reforming (AAOSR) has been explored mainly at autothermal conditions (ATR). Research such as that of [PERSON] et al. [36] evaluated the effect of Y-doping Ni/CeO\({}_{2}\) catalysts in ATR at 700 \({}^{\circ}\)C, with a molar ratio of H\({}_{\text{AC}}\)/H\({}_{\text{2}}\)O/O\({}_{2}\)/N\({}_{2}\) = 1/4/0.28/3, and GHSV = 50,600 mL/(g\(\cdot\)h). Results showed that the NCY10 catalyst (14.4 wt\(\%\) NiO, 75.7 wt\(\%\) CeO\({}_{2}\), 9.9 wt\(\%\) YO\({}_{1.5}\)) achieved complete conversions during 10 h of reaction, with a 2.6 mol-H\({}_{2}\)/mol AcOH stable yield. In addition, for the catalyst used, TGA analysis did not show evidence of coke formation, suggesting a high stability of the system. Furthermore, [PERSON] et al. [37] synthesized mesoporous Ni-xSm-Al-O catalysts to evaluate the Sm doping effect on the catalyst. A high surface area, strong basicity and weak acidity, and highly dispersed Ni\({}^{0}\) crystals with a mean crystallite size of 9.9 nm were observed after doping with 2% Sm. These characteristics enhanced the catalytic activity (T = 700 \({}^{\circ}\)C, P = 1 atm; GHSV = 30,000 mL/(g-h), and a molar ratio of HAc/H\({}_{2}\)O/O\({}_{2}\)/N\({}_{2}\) = 1/4/0.28/3.90), with 100% acetic acid and H\({}_{2}\) yield conversions of 2.6 mol-H\({}_{2}\)/mol AcOH achieved during 30 h of reaction. Some recent work by [PERSON] et al. [25,38] was focused on nickel-based catalysts with different supports, highlighting the Ni/Ce-m catalyst, which achieved conversions around 97% during 5 h of reaction (T = 500 \({}^{\circ}\)C, P = 1 atm; GHSV = 11,000 h\({}^{-1}\), and a molar ratio HAc/H\({}_{2}\)O/O\({}_{2}\) = 1/2/0.08). Nevertheless, a coke formation of 120.6 mg\({}_{\text{coke}}\)-gcat\({}^{-1}\).h\({}^{-1}\) was reported, thus leading to the La\({}_{2}\)O\({}_{3}\) addition, enhancing the dispersion of the metallic phase as well as significantly lowering the carbon deposition to 62.3 mg\({}_{\text{coke}}\)-gcat\({}^{-1}\).h\({}^{-1}\). Lastly, Co-Rh/CeO\({}_{2}\) bimetallic catalysts [39] exhibited long-term stability during 25 h (T = 600 \({}^{\circ}\)C, P = 1 atm; WHSV = 30.1 h\({}^{-1}\), and a molar ratio HAc/H\({}_{2}\)O/O\({}_{2}\) = 1/2/0.08). The studies highlight the relevance of AAOSR and the importance of further optimization of the catalyst formulation to improve process efficiency, selectivity toward H\({}_{2}\), and stability against deactivation. Although CeO\({}_{2}\) has been widely recognized for enhancing catalytic dispersion and coke resistance, most previous studies have focused on Ni-based catalysts on reforming reactions under autothermal conditions. Based on the above, the effect of the incorporation of CeO\({}_{2}\) in the catalytic performance of a Co-based catalyst supported over SBA-15 in the AAOSR was evaluated.