Synthesis gas, a mixture of carbon monoxide and hydrogen (H2/CO) can be converted into hydrocarbons using cobalt (Co) catalysts during Fischer Tropsch Synthesis (FTS). Cobalt is well known for its activity in FTS and is typically supported on metal oxides, chiefly Al2O3 or SiO2. Extensive efforts have been made to develop FTS catalysts with high activity and high C_(5+) selectivity [1,2] and the prospect of using ordered porous carbon materials as support for Co catalysts was previously introduced to minimize or even by-pass the catalyst-support-interactions typically encountered for small cobalt particles [3]. Carbon support structures have been shown to influence the reactivity and product distribution during FTS and for Co catalysts the activities for various mesoporous carbon supports were previously assessed [4]. Carbon support structures are an appealing alternative to metal oxides since the surfaces can be manipulated with appropriate surface functionalization and surface areas can be enhanced through physical and chemical treatments [5]. However, there are great variations in carbon support materials including fibers, nanotubes, nanowires and molecular sieves, just to mention a few, and they may produce many different outcomes for FTS [6]. The current study focuses on hydrothermally-derived carbon spheres as a support for Co nanoparticles. Carbonaceous materials made from the hydrothermal process are unique in that properties such as microstructure, surface functionality, size, morphology, chemical composition, surface area and micro- and meso-porosity can be tailored by the selection of the carbohydrate precursor and synthetic growth conditions. The hydrothermal synthesis (HTS) process for generating carbonaceous materials in the form of nano- and microspheres can use mono- and polysaccharides
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