Hydrogen production from acetic acid-phenol steam reforming over bimetallic nickel-cobalt supported on lanthanum oxide-gamma aluminum oxide catalyst

摘要

Hydrogen has been recognized as a sustainable and renewable energy carrier for the portable application. Acetic acid and phenol are considered as the unwanted product in the bio-oil derived from the pyrolysis of biomass. This study is to propose the catalytic steam reforming of the mixture over bimetallic Nickel-Cobalt (Ni-Co) supported on Lanthanum (III) Oxide (La2O3) and gamma-aluminum oxide (?- Al2O3). The scope of works including the catalyst characterization and the catalyst testing in a fixed bed reactor operated at ambient pressure. The catalyst performance tests are carried out in a fixed bed reactor at atmospheric pressure and temperature from 600°C to 800°C to compare the catalyst dilution, feed flow rate in the range of 0.16 to 0.56 mL/min, and the catalyst weight of 0.1 to 0.3 g. The acidity of the prepared catalyst is less than ?-Al2O3 but higher than La2O3. The total surface area of the fresh catalyst decreased by exposing in the reaction from 48 to 30 m2/g. It was found that the maximum feed conversion achieved 99.99% for acetic acid and 95.5% conversion for phenol at 800 oC in the effect of temperature by using catalyst dilution of silicone carbide (SiC). Instead, hydrogen yield and mole fraction decreased with the presence of dilution. The highest temperature of 800 oC in this study, and the other parameters like 0.2 gram catalyst and 0.36 ml/min flow rate achieved the highest hydrogen gas which was about 98%. It was resulted that the presence of SiC was able to increase the conversion of feed due to extension of residence time but it affected negatively in hydrogen yield. Hydrogen production also increased by increasing of phenol and acetic acid concentration. The catalyst did not show a significant deactivation for the period of study. This catalyst is promising for the real application