Improved catalytic performance of encapsulated Ru nanowires for aqueous-phase Fischer–Tropsch synthesis†
Abstract
Fischer–Tropsch (F–T) synthesis at low temperature has attracted a lot of research attention due to its thermodynamically favorable nature at low temperature. Herein, we report a highly efficient solid nanoreactor for low temperature liquid-phase F–T synthesis. The solid nanoreactor was fabricated by encapsulation of Ru–PVP nanowires in ethane–silica hollow nanospheres via a one-pot co-condensation method. Under similar reaction conditions, the solid nanoreactor shows higher activity (activity: 6.35 versus 5.96 molCO mol−1Ru h−1) and selectivity towards oxygenate products (41.3 versus 21.6%) than free Ru–PVP in aqueous F–T synthesis. The high activity and selectivity of the encapsulated Ru–PVP is mainly attributed to the low PVP/Ru ratio and the unique yolk–shell nanostructure in increasing the degree of exposure of the active sites. It was also observed that the selectivity towards C5–12 products could be increased to 63.8% in a water/cyclohexane biphasic system. Encapsulation not only gave rise to the quasi-homogeneous Ru–PVP with facile recycling ability, but also enhanced its activity and selectivity towards oxygenates.