The catalytic CO hydrogenation is one of the most versatile large-scale chemical syntheses leading to variable chemical feedstock. While traditionally mainly methanol and long-chain hydrocarbons are produced by CO hydrogenation, here we show that the same reaction can be tuned to produce long-chain n-aldehydes, 1-alcohols and olefins, as well as n-paraffins over potassium-promoted CoMn catalysts. The sum selectivity of aldehydes and alcohols is usually >50 wt% whereof up to ∼97% can be n-aldehydes. While the product slate contains ∼60% n-aldehydes at /pCO=0.5, a 65/35% slate of paraffins/alcohols is obtained at a ratio of 9. A linear Anderson–Schulz–Flory behaviour, independent of the /pCO ratio, is found for the sum of C4+ products. We advocate a synergistic interaction between a Mn5O8 oxide and a bulk Co2C phase, promoted by the presence of potassium, to be responsible for the unique product spectra in our studies.

We show that long-chain 1-alcohols can be produced with high selectivities using heterogeneous CO hydrogenation catalysis. This breakthrough is achieved through the targeted design of "CoCuMn" nanosized core-shell particles using co-precipitation of metal salts into oxalate precursors and subsequent thermal decomposition. Using stoichiometric CO/H2 feeds, the selectivities to 1-alcohols or combined 1-alcohols/1-alkenes are usually higher than 60% and occasionally up to 95%. The Anderson-Schulz-Flory chain-lengthening probabilities for these products are higher than 0.6, but usually below 0.9 so as to optimize the C8-C14 slate as feedstock for plasticizers, lubricants, or detergents.

Bimetallic CoCu model catalysts were investigated for the synthesis of higher alcohols using catalytic CO hydrogenation according to the Fischer−Tropsch technology. Emphasis was placed on revealing the influence of the activation conditions. Accordingly, catalyst precursors were activated in argon, hydrogen, syngas (CO/H 2 ), and CO under atmospheric conditions and at elevated temperatures (370 °C). All catalyst precursors were prepared via oxalate coprecipitation in the absence of a classic support. Alcohol selectivities between 30 and ∼40% (up to ∼50% for the sum of alcohols and alkenes) were obtained with an Anderson−Schulz−Flory (ASF) chain lengthening probability maximizing the slate up to C 6 . Detailed catalysis and characterization studies were performed using a Co 2 Cu 1 catalyst composition. The catalytic performances of the H 2 -and syngas-activated Co 2 Cu 1 catalyst were similar. While the CO-activated catalyst shows significantly higher catalytic activity and ASF chain lengthening probability, the alcohol selectivities are lower than those of H 2 -or syngas-activated ones. All catalysts required time on stream for several hours to achieve steady-state catalytic performance. Co 2 Cu 1 catalysts were characterized by temperature-programmed decomposition (TPDec), in situ N 2 physisorption (Brunauer−Emmett−Teller), transmission electron microscopy (TEM), and in situ X-ray photoelectron spectroscopy (XPS). The data indicate major restructuring occurs during activation. An "onion-like" graphitic carbon shell was observed via TEM for the CO-activated Co 2 Cu 1 catalyst, which probably originated mainly from the Boudouard reaction (2CO + [ ] ad → C ad + CO 2 ). This interpretation is in accordance with the TPDec profiles and XPS results. The latter also indicates that syngas and CO activation lead to higher than nominal Co/Cu surface ratios. The surface segregation of Co in the presence of CO atmospheres is interpreted on the basis of Co@Cu core−shell structured particles.

Optimal ethane-to-aromatics catalyst design requires carefully tuning metal and zeolite catalytic sites to work in conjunction.