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Here, we show that C 4 –C 12 linear olefins, including linear alpha olefins, can be selectively produced from ethylene over a stable cobalt oxide on carbon catalyst. Both bulk and surface cobalt phases are CoO when the catalyst is stable, suggesting CoO is the stable cobalt phase for oligomerization. During the reaction, polyethylene forms in the catalyst pores which influences the product selectivity. The catalyst is more stable at higher temperatures (∼200 °C) likely due to reduction of Co 3 O 4 to CoO while rapid deactivation is observed at lower temperatures ( e.g. , 80–140 °C). The product selectivity can be fit to two different Schulz Flory distributions, one from C 4 to C 10 olefins and one above C 10 olefins, suggesting that transport restrictions influence product selectivity. At 48.3% conversion, product linearities up to C 12 olefins are above 90%, making it the most selective heterogeneous catalyst to linear olefins to date in the absence of activators and/or solvents. 

Biomass conversion to alcohols using supercritical methanol depolymerization and hydrodeoxygenation (SCM-DHO) with CuMgAl mixed metal oxide is a promising process for biofuel production. We demonstrate how maple wood can be converted at high weight loadings and product concentrations in a batch and a semi-continuous reactor to a mixture of C 2 –C 10 linear and cyclic alcohols. Maple wood was solubilized semi-continuously in supercritical methanol and then converted to a mixture of C 2 –C 9 alcohols and aromatics over a packed bed of CuMgAlO x catalyst. Up to 95 wt% of maple wood can be solubilized in the methanol by using four temperature holds at 190, 230, 300, and 330 °C. Lignin was solubilized at 190 and 230 °C to a mixture of monomers, dimers, and trimers while hemicellulose and cellulose solubilized at 300 and 330 °C to a mixture of oligomeric sugars and liquefaction products. The hemicellulose, cellulose, and lignin were converted to C 2 –C 10 alcohol fuel precursors over a packed bed of CuMgAlO x catalyst with 70–80% carbon yield of the entire maple wood. The methanol reforming activity of the catalyst decreased by 25% over four beds of biomass, which corresponds to 5 turnovers for the catalyst, but was regenerable after calcination and reduction. In batch reactions, maple wood was converted at 10 wt% in methanol with 93% carbon yield to liquid products. The product concentration can be increased to 20 wt% by partially replacing the methanol with liquid products. The yield of alcohols in the semi-continuous reactor was approximately 30% lower than in batch reactions likely due to degradation of lignin and cellulose during solubilization. These results show that solubilization of whole biomass can be separated from catalytic conversion of the intermediates while still achieving a high yield of products. However, close contact of the catalyst and the biomass during solubilization is critical to achieve the highest yields and concentration of products.