Solvent-free Semihydrogenation of Acetylene Alcohols in a Capillary Reactor coated with a Pd-Bi/TiO2 Catalyst
نویسندگان
چکیده
A solvent-free semihydrogenation of 2-methyl-3-butyn-2-ol (MBY) to 2-methyl-3-buten-2-ol was performed in a capillary reactor (10 m long, 0.53 mm i.d.) coated with a titania supported Pd-Bi catalyst. Several coatings with different Pd/Bi ratio have been prepared. The catalysts have been characterized with SEM, TEM, EDX, XRD analysis and N2 adsorption-desorption measurements. The maximum alkene yield of 90 % was obtained at a molar Pd/Bi ratio of 11. The yield was increased to 95 % in the presence of 10 mol. % pyridine in the reaction mixture. The alkene selectivity decreased with time due to leaching of Bi. The leaching was fully suppressed in the presence of 1 vol. % acetic acid in the reaction mixture. The catalyst remained stable for 100 hours of continuous operation. The results demonstrate that capillary reactors provide alkene selectivity the same compared to ideal stirred tank
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