Liquid transportation fuels from biomass-derived oxygenates: Gas-phase 2-hexanol upgrading on Cu-based mixed oxides

Hollow @CuMgAl double layered hydrotalcites and mixed oxides with tunable textural and structural properties, and thus enhanced NH3-NOx-SCR activity

“…In our study, reduction begins at temperatures as high as 260 °C (for @CuMgAl_0.05-MO) and gradually drops to 140 °C (for @CuMgAl_0.5-MO). A similar stabilisation of the Cu species deposited on pure MgO and on MgAl mixed oxides was recently reported by Basąg et al 77 and Luggren et al 79 Other possible explanations could be the formation of more aggregated Cu-species (still under XRD detection level) dispersed in the samples that have higher Cu content. Possibly, these more aggregated species are more easily reduced than smaller ones.…”

Deactivation of Cu–Mg–Al mixed oxide catalysts for liquid transportation fuel synthesis from biomass-derived resources

“…Also, the bifunctional Cu°/acid-base nature of the catalytic process was discussed earlier for ZCuMgAl oxides and other similar catalysts [11,13]. We demonstrated that both, the rate-limiting step (r.l.s.)…”

“…On-line analysis of the reaction products was carried out by gas chromatography using an Shimadzu GC-2014 chromatograph equipped with flame ionization detector and a (5% Phenyl)-methylpolysiloxane HP-5 Agilent capillary column. More details are given elsewhere [11]. Main products were coded as CnH (hydrocarbons), CnK (saturated ketones), CnUK (unsaturated ketones) and CnOL (alcohols), where n stands for the carbon atom number in the molecule (n = 3, 6, 9, 12, 15, 18, 21 and 24).…”

“…These catalysts combine a metallic function provided by Cu°atoms and acid-base sites (M-O pairs; M: Mg 2+ and Al 3+ ). A detailed characterization of these materials was reported in previous works [11,13]. A summary of the main physicochemical properties of the ZCuMgAl oxides is given in Table 1.…”

“…In particular, 2-hexanol is obtained as the main constituent of the secondary C4-C6 alcohol fraction [10]. We recently reported the synthesis of liquid transportation fuel precursors on Cu-Mg-Al catalysts, at mild conditions and using 2-hexanol as a model "platform molecule" [11][12][13]. We showed that through a series of consecutive steps comprising dehydrogenation/CeC coupling/dehydration/hydrogenation reactions, high yields (≈90%) of C9-C24 oxygenates and hydrocarbons can be obtained.…”