Highly selective 1-butanol obtained from ethanol catalyzed by mixed metal oxides: Reaction optimization and catalyst structure behavior

Ethanol Guerbet Condensation to n‐Butanol or C4‐C8 Alcohols over Ni/TiO2 Catalyst

“…In general, reaction time had an insignificant effect on ethanol Guerbet condensation. Consequently, selectivity of n-butanol and C 4 -C 8 alcohols reached separately up to 41.7% and 69.7% at an ethanol conversion of 49.2% under the conditions of a catalyst dosage of 10 wt.%, a reaction temperature of 210°C, and a reaction time of 10 h, indicating that compared with other literatures, [6][7][8][9][10][11] Ni/TiO 2 catalyzed ethanol Guerbet condensation had the advantages of a lower reaction temperature, a higher ethanol conversion under similar reaction conditions and higher selectivity of n-butanol and C 4 -C 8 alcohols at a close ethanol conversion.…”

“…Jordison et al [8] used Ni/γ-Al 2 O 3 to catalyze ethanol Guerbet condensation and obtained a n-butanol selectivity of 47.5% at an ethanol conversion of 41% at 230°C for 10 h. However, water as a by-product of Guerbet condensation led to deactivation of catalyst by turning γ-Al 2 O 3 into inactive boehmite. Pang et al [9] catalyzed conversion of ethanol to nbutanol on a highly dispersed Ni-MgAlO and found that nbutanol selectivity was 55.2% at an ethanol conversion of 18.7% at 553 K. Siqueira et al [10] prepared a copper mixed metal oxide derived from hydrotalcite precursor for ethanol conversion to 1-butanol and reached an ethanol conversion of 79.6% into gaseous phase (69% of yield) and condensed phase (31% of yield) products using a batch reactor at 350°C for 5 h. A high yield of gaseous phase products indicated that severe cracking reactions occurred. The main product of the condensed phase was 1-butanol with 25.4% yield and 32% selectivity.…”

Multifunctional Catalysts for Direct Conversion of Alcohols to Long-Chain Hydrocarbons via Deoxygenative Olefination

“…The latter necessitates the design of active and selective supported catalysts tailored for the tandem processes required to upgrade biomass-derived alcohols. Current approaches to upgrading alcohols primarily rely on Guerbet condensation, which affords longer-chain, branched primary alcohols through sequential dehydrogenation, aldol condensation, and hydrogenation reactions (Scheme , Reaction A ). − The latter can be catalyzed by supported noble metal catalysts, metal oxides, and mixed metal oxides (MMOs). ,,− ,− …”

Condensed-Phase Ethanol Conversion to Higher Alcohols over Bimetallic Catalysts

“…Guerbet reaction catalysts must be multifunctional, having metal or electron-deficient metal oxide surface sites for dehydrogenation and hydrogenation, and basic and acidic sites for aldol condensation. The most closely examined heterogeneous catalysts to date include Mg–Al mixed oxides, ,,− hydroxyapatites (HAPs), − metal-containing CeO 2 supports, ,, and other metal combinations. ,− Homogeneous catalysts involving metal complexes and phosphine ligands have also shown high selectivity to n- butanol, but thermal instability and separation/recovery costs remain as challenges to the use of homogeneous catalysts. ,− …”