Development of cobalt–copper nanoparticles as catalysts for higher alcohol synthesis from syngas

• Published in: Catalysis today 2009-09, Vol.147 (2), p.100-106
• Main Authors: Subramanian, Nachal Devi, Balaji, G., Kumar, Challa S.S.R., Spivey, James J.
• Format: Article
• Language: English
• Subjects: Catalysis; Chemistry; CO hydrogenation; Colloidal state and disperse state; Core–shell nanoparticles; Exact sciences and technology; General and physical chemistry; Higher alcohols; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Syngas; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry
• ISSN: 0920-5861; 1873-4308
• DOI: 10.1016/j.cattod.2009.02.027

The synthesis of higher alcohols from syngas has been studied over different types of Cu-based catalysts. In order to provide control over the catalyst composition at the scale of a few nanometers, we have synthesized two sets of Co–Cu nanoparticles with novel structures by wet chemical methods, namely, (a) cobalt core–copper shell (Co@Cu) and (b) cobalt–copper mixed (synthesized by simultaneous reduction of metal precursors) nanoparticles. These catalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and temperature programmed reduction (TPR). The catalysts were tested for CO hydrogenation at temperatures ranging from 230 °C to 300 °C, 20 bar and 18,000 scc/(hr.gcat). It was observed that the Co–Cu mixed nanoparticles with higher Cu concentration exhibit a greater selectivity towards ethanol and C 2+ oxygenates. The highest ethanol selectivity achieved was 11.4% with corresponding methane selectivity of 17.2% at 270 °C and 20 bar.