(132d) Reactivity and Carbon Deposition Study On Steam Reforming of Bio-Oil

Two major concerns with the utilization of fast-pyrolytic oil (bio-oil) as a biofuel are its high oxygen and water contents, which makes it unstable and difficult to process. Improving the stability of bio-oil and upgrading bio-oil into bio-fuels requires a large amount of hydrogen. Commercially, hydrogen is synthesized from natural gas or petroleum oil. For upgrading bio-oil, the hydrogen required can be generated from steam reforming of specific fractions of bio-oil. It has been shown that bio-oil fractions composed mainly of low molecular weight compounds, which are soluble in water, are more favorable to the production of hydrogen compared to the higher molecular weight components, which are typically insoluble in water. However, even with bio-oil fractions containing low molecular weight compound in water, the production of hydrogen by steam reforming is still challenging. Catalyst deactivation by coking and a high degree of thermal decomposition are the major known limitations, although the responsible components in the water soluble fractions are not yet identified due to the complexity of the mixture. As an effort to identify the key components that contribute most significantly to coking in reforming bio-oil, a study using selected model compounds representing different types of functionalities in bio-oil has been performed. The goal of the study is to determine relative reactivities and tendencies to generate surface carbon. Acetic acid, furfural and levoglucosan were chosen to model carboxylic acids, aldehydes, and anhydrosugars respectively. These feedstocks were tested in a small fixed bed catalytic reactor in the presence of excess steam under kinetically controlled conditions. These results will help determine what types of bio-oil fractions are more desirable for reforming while minimizing conversion limitations.