Fabrication of a Bimetallic SF/NZVI/Ni Catalyst and Its Efficacy in Enhancing the Biomass Liquefaction Process

Biomass energy is a sustainable, environmentally friendly, and carbon-neutral alternative energy source. Although the use of biomass in the liquefaction process is quite common, the process of improving bio-oil production and its quality is still ongoing. In this study, a silica fume (SF) supported nano zero-valent iron/nickel (NZVI/Ni) bimetallic catalyst was synthesized using the liquid-phase reduction method to achieve effective liquefaction. The characterization of the catalyst was performed using various techniques, revealing the formation of an active surface area on the catalyst and the presence of nano-metallic structures." Subsequently, the effectiveness of the catalyst in the liquefaction of walnut shells (WS) was investigated. According to the obtained results, the (oil + gas) yield was 42.5% under non-catalytic conditions, while it was found to be 56%, 59.1%, and 63.4% when 1%, 3%, and 6% catalyst was added, respectively. The biochar yield was 10.17% under non-catalytic conditions, and it decreased as the catalyst ratio increased, dropping to 8.13% with 6% catalyst. The characterization of the bio-oils by GC-MS revealed that they consisted of aromatic components such as indane and its derivatives and polyaromatic components such as naphthalene and its derivates.