Hydrodeoxygenation of Pinyon-Juniper Catalytic Pyrolysis Oil

Catalytic hydrodeoxygenation (HDO), is an effective process to convert oxygenated compounds to hydrocarbons. This process is widely used for improving the negative properties of biomass-derived pyrolysis oils (bio-oils) such as high acidity, poor stability, and low heating value. During this process oxygen is removed from the bio-oil in the form of water, thus the liquid product of HDO process consists of aqueous phase and hydrocarbon phase that can be easily separated. Synthesis of efficient HDO catalyst has been a major challenge in the field of bio-oil upgrading. Red mud, which is an alkaline waste from alumina industry was used to develop a new red mud-supported nickel catalyst (Ni/RM) for the HDO of pinyon-juniper catalytic pyrolysis oil. The new catalyst was more effective than the commercial Ni/silica-alumina catalyst for the HDO of organic phase pyrolysis oil, the aqueous phase pyrolysis oil, and bio-oil model compounds. Less hydrogen was consumed in the case of Ni/RM and more liquid hydrocarbon yield was obtained compared to the commercial catalyst. In addition to HDO reactions, the Ni/RM catalyst catalyzed ketonization and carbonyl alkylation reactions that was important to produce liquid hydrocarbon from low molecular weight oxygenated compounds. Unlike the commercial catalyst, Ni/RM was regenerable by burning off the deposited coke and activation by reduction using hydrogen.