Higher alcohol synthesis over nickel-modified alkali-doped molybdenum sulfide catalysts prepared by conventional coprecipitation and coprecipitation in microemulsions

• Published in: Catalysis today 2015-12, Vol.258, p.294-303
• Main Authors: Suárez París, Rodrigo, Montes, Vicente, Boutonnet, Magali, Järås, Sven
• Format: Article
• Language: English
• Subjects: Higher alcohols; K/MoS2; Microemulsion; Nickel; Syngas
• ISSN: 0920-5861; 1873-4308; 1873-4308
• DOI: 10.1016/j.cattod.2014.12.003

•A novel K-Ni-MoS2 catalyst was synthetized by coprecipitation in microemulsions.•The novel catalyst shows better performance than a conventional K-Ni-MoS2 sample.•Ethanol yield is especially enhanced with the new preparation method.•The greater enrichment of K and Ni on the surface could explain the improvement. Ethanol and higher alcohols are one of the most interesting alternatives to replace fossil fuels in the transportation sector. Nickel-modified alkali-doped molybdenum sulfide is a potential catalyst for the conversion of syngas to mixed alcohols. In this work, K-Ni-MoS2 catalysts were synthetized by coprecipitation in aqueous solution or in microemulsions, followed by alkali doping. The influence of the preparation route in CO hydrogenation was investigated at 91bar, 340/370°C and GHSV=2000–14,000NmL/hgcatalyst. The catalysts were also characterized by TGA, ICP, XPS, nitrogen adsorption, XRD, SEM-EDX and TEM. The novel microemulsion catalyst outperformed the conventional one, resulting in higher yields of ethanol and higher alcohols. The higher activity and selectivity was attributed to a higher concentration of promoters on the microemulsion catalyst surface, together with a lower degree of crystallinity.