Selective Catalytic CO Hydrogenation to Short- and Long-Chain C 2+ Alcohols Yizhi Xiang • Ve´ronique Chitry • Norbert Kruse Received: 24 May 2013 / Accepted: 28 June 2013 Ó Springer Science+Business Media New York 2013 Abstract We show that the CO hydrogenation over CoCu-based catalysts can be tuned so as to produce either short- or long-chain 1-alcohols with high selectivities. This breakthrough is achieved by ‘‘alloying’’ these catalysts with Mn or Mo thereby creating either ‘‘CoCuMn’’ or ‘‘CoCuMo’’ in various relative composition. Catalysts are prepared via co-precipitation of mixed oxalate precursors, except ‘‘CoCuMo’’ for which the co-precipitation of CoCu oxalate is combined with the precipitation of MoO x using solubility effects. Both ‘‘CoCuMn’’ and ‘‘CoCuMo’’ cata- lysts produce 1-alcohols or combined 1-alcohols/1-alkenes with selectivities of more than 60 % at temperatures between 170 and 240 °C. CoCuMo catalysts show a double Anderson–Schulz–Flory (ASF) chain-lengthening distri- bution. Under conditions of low CO conversion, the overall selectivity of 1-alcohols may rise to over 95 % for Co 1 Cu 5 Mo 1 catalysts. The ASF chain-lengthening proba- bility for Co 1 Cu 1 Mn 1 may be adjusted to *0.6–0.7 so as to maximize the C 8 –C 14 1-alcohol slate as feedstock for plasticizers, lubricants or detergents. Keywords CO hydrogenation  Long chain 1-alcohols  CoCu-based catalysts  Mo  Mn 1 Introduction Various patents filed by Badische Anilin und Soda Fabrik (BASF) in the period 1913–1916 claimed the formation of liquid hydrocarbons and water-soluble oxygenates during the hydrogenation of carbon monoxide at elevated pres- sures and temperatures [1, 2]. It would appear, however, that rather than pursuing this disclosure, BASF for various reasons gave priority at that time to the fast commerciali- zation of ammonia synthesis. One of the obvious chal- lenges was undoubtedly the delicate process control in CO hydrogenation and the cumbersome handling of a wide range of products, as modern characterization and identi- fication methods like chromatography, mass spectrometry, and infrared or nuclear resonance spectroscopy were sim- ply not available in these early days of large-scale process development. The first scientific publication on CO hydrogenation did not appear until 10 years later when Fischer and Tropsch reported the formation of an ‘‘oily fraction’’ after applying high-pressure synthesis conditions over an iron–alkali catalyst [3–5]. Contrary to the earlier BASF patent claims, when operating CO hydrogenation in an excess of hydrogen, these authors found the oily product fraction to exclusively contain oxygenates (‘‘synthol’’). It was, however, the privilege of Roelen to discover the oxo- synthesis, also conveniently referred to as ‘‘hydroformyl- ation’’ [6]. Not by chance, this major discovery was ren- dered possible following detailed investigations in which Roelen explored the prospects for recycling ‘‘gasol’’ (light hydrocarbons, including olefins and, in particular, ethyl- ene) so as to increase the chain-lengthening during Fischer–Tropsch (FT) synthesis. It is interesting to note that Roelen considered the oxo-process to be a case of heterogeneous rather than homogeneous catalysis. The generation of tetracarbonyl hydride cobalt, HCo(CO) 4 , as Electronic supplementary material The online version of this article (doi:10.1007/s10562-013-1060-0) contains supplementary material, which is available to authorized users. Y. Xiang  V. Chitry  N. Kruse (&) Chemical Physics of Materials (Catalysis-Tribology), Universite´ Libre de Bruxelles, Campus Plaine, CP 243, 1050 Bruxelles, Belgium e-mail: nkruse@ulb.ac.be 123 Catal Lett DOI 10.1007/s10562-013-1060-0