Improved Selectivity of Long-Chain Products from Aqueous Acetone–Butanol–Ethanol Mixture over High Water Resistant Catalyst Based on Hydrophobic SBA-16

Abstract

Water resistance and/or hydrothermal stability of catalysts are key concerns during the obtention of biofuels from fermentation products, which always involve considerable amounts of water. Herein, aimed at efficient upgrading of a water-containing acetone–butanol–ethanol (ABE) fermentation mixture to long-chain products, we designed and synthesized a series of 10 wt % Ni–MgO–SBA-16 catalysts, which were based on hydrophobic SBA-16 with highly condensed structures. These catalysts exhibited low water adsorptive capacities and relatively favorable hydrophobicity. As expected, the as-prepared catalysts showed excellent catalytic activity and water-tolerance: 76.4% conversion and 90.5% selectivity for C5–15 species were achieved under solvent-free conditions; when the initial water content increased to 7.4 wt %, comparable conversion and total selectivity for C5–15 species were also achieved. Besides, on account of the hydrophobic surface, monoalkylation products readily converted into doublealkylation ones even under conditions of high water content. The results demonstrated the 10 wt % Ni–MgO–SBA-16 catalysts acted as the role of “killing two birds with one stone”: promoting the water tolerance and exhibiting high hydrothermal stability; suppressing competitive adsorption of water molecules and facilitating the adsorption and transformation of hydrophobic intermediate 2-heptanone to long-chain hydrocarbons; replacing the rare noble metal by base metal and complying with the principles of “green chemistry”. Overall, this work not only makes significant progress in value-adding of water-containing ABE but also provides the rational synthetic direction of catalysts requiring high hydrothermal stability and/or water resistance in the biomass conversion process.

Domino Reactions for Biofuel Production from Zymotic Biomass Wastes over Bifunctional Mg-Containing Catalysts

“…As reported by Fu and Gong, − Ni nanoparticles were catalytically active for alcohol steam reforming in which dehydrogenation of alcohols, decarbonylation of aldehydes, water–gas shift reaction, and CH 4 transformation are involved as follows. Similar results were also reported in our previous work The effect of the reaction time on catalytic performance is shown in Figure B.…”

“…It has been proved that a high catalytic activity for the alkylation process depends on the cooperation of acid and base sites. 19,20 On the basis of these works, we are motivated to design and prepare Ni−CaO−MgO (denoted as Ni/CaMgO) and Ni supported on magnesium silicate (denoted as Ni/MgSiO) as the catalysts for the C−C coupling and the HDO reaction, respectively. There may be two possible advantages of choosing Mg-decorated support.…”

“…In our previous work, MgO–SiO 2 -based catalysts were successfully prepared and applied in converting the ABE mixture into ketones and alcohols under solvent-free conditions. It has been proved that a high catalytic activity for the alkylation process depends on the cooperation of acid and base sites. , …”

High‐Performance Heterogeneous Thermocatalysis Caused by Catalyst Wettability Regulation

“…(c) Recycling tests of 10 wt% Ni−MgO−SBA‐16 180 for ABE upgrade under initial water content of 7.4 wt%. (a–c) Reproduced with permission [61a] . Copyright 2019, American Chemical Society.…”

Upgrading n-Butanol to Branched Alcohols over Ni/CaxMgyO

“…The Guerbet reaction is involved in the reaction systems for upgrading acetone–butanol–ethanol (ABE) fermentation mixtures to biofuels and a series of efficient heterogeneous catalysts have been developed in our previous works. − These scenarios motivate us to go a step further by focusing on a deeper understanding of the active sites and synergistic effect during n -butanol condensation.…”