Rough-surface hydroxyl-group-rich hollow mesoporous silica nanospheres with nanocellulose as a template to improve the oxidation stability of bio-oil

Bio-oils are good substitutes for petrochemical oil, but their high oxygen contents result in poor oxidation stability. Therefore, anti-oxidants are essential to improve the oxidation stability of bio-oils. In this study, quantum chemistry has been used to analyze in detail the relationship between the structure and adsorption properties of bio-oils and silanol groups. A new type of rough-surface hollow mesoporous silica nanospheres (R-nCHMSNs) bearing abundant hydroxyl groups has been prepared using hydroxyl-group-rich nanocellulose as a template. In an evaluation of anti-oxidants for bio-oil, R-nCHMSNs showed excellent anti-oxidant properties. They formed hydrogen or ester bonds with oxygen-containing groups in bio-oil through their surface hydroxyl groups and wide channel structure, thus improving the oxidation stability of the bio-oil. Furthermore, the kinetics of adsorption of bio-oil on the R-nCHMSNs has been found to be in accordance with a second-order model.