PdCu nanoalloy supported on alumina: A stable and selective catalyst for the conversion of bioethanol to linear α-alcohols

Effects of Support on the Formation and Activity of Gold Catalysts for Ethanol Conversion to Butanol

“…The most active catalysts for ethanol conversion by mechanism II are Pd/Al 2 O 3 and Ni/Al 2 O 3 composites [11,12]. At 270°C, the ethanol conversion over 0.1%Pd/Al 2 O 3 is 24%, and the butanol selectivity is 70% [13]. At 250°C, the ethanol conversion over 20%Ni/Al 2 O 3 is 25%, and the butanol selectivity is 70% [11].…”

“…At 250°C, the ethanol conversion over 20%Ni/Al 2 O 3 is 25%, and the butanol selectivity is 70% [11]. Despite the high initial effi ciency of Pd-and Ni-catalysts, they both have low performance stability, which is manifested in a slowdown of butanol synthesis by 80-95% after 12-20 h of service [11,13]. The Pd/Al 2 O 3 deactivation is caused by a side acetaldehyde decarbonylation process followed by chemisorption of the CO product on Pd active sites.…”

“…EXPERIMENTAL Supports and catalysts. We used the following certified supports: Al 2 O 3 [AOK-63-11 (V grade), manufactured by the Angarsk Catalyst and Organic Synthesis Plant, Irkutsk Region, Russia, 1.0 mm pellets, γ-Al 2 O 3 phase [13]); TiO 2 (Aerolyst®7710, Evonik, 1 mm extrudates, anatase); ZrO 2 (Aerolyst®6100, Evonik, 2 mm extrudates, monoclinic); carbon support (Sibunite, manufactured by the Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia, 1 mm pellets, X-ray amorphous [22]); and SiO 2 (No. 288616, Aldrich, 0.4 mm pellets, X-ray amorphous).…”

“…NH 3 -TPD. The acidity of the samples was measured by ammonia temperature-programmed desorption (NH 3 -TPD) on a USGA-101 chemisorption analyzer [13]. For this purpose, 0.2 g of the sample was placed in a quartz reactor and calcined under a He fl ow at a fl ow rate of 20 mL/min at 400°C for 1 h. The reactor was cooled to 25°C, and the sample was saturated with ammonia vapor for 30 min.…”

“…Catalytic conversion of ethanol. The catalytic tests were carried out on a Parr 5000 Series autoclave-type unit at 275°C (pre-selected optimal temperature) [13,21]. In the standard experiment setting, 30 mL of ethanol and 5 g of the catalyst were placed in the reactor.…”