The activity of a commercial alumina, after a preliminary characterization, was investigated in epoxidation\ud with soybean oil with aqueous hydrogen peroxide. Results show that the g-alumina was an efficient catalyst.\ud The role of the solvent in the epoxidation reaction in the presence of alumina was investigated. A “noinnocent”\ud solvent role was demonstrated. Moreover, the optimization of the methyl oleate epoxidation\ud reaction with alumina was eventually valuated, varying the type of the solvent and concentration of\ud hydrogen peroxide in order to obtain a product with commercial features

We describe the use of a decationated Y zeolite as a promising catalyst for the epoxidation of soybean oil with hydrogen peroxide and formic acid. The pores of this zeolite are too narrow for the oil molecules that remain outside the zeolite framework (shape selectivity), while, all the molecules of the aqueous mixture can enter and react inside the pores to form in situ the reactant performic acid, the formation of which is catalyzed by an acid environment. Because of the absence of mineral acid in the aqueous solution, outside the pores, the undesired side reactions of ring opening are limited. The most opportune operative conditions and zeolite pretreatments for improving activity and selectivity will be described.

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Alkenols are commercially important chemicals employed in the pharmaceutical and agro-food industries. The conventional production route via liquid phase (batch) alkynol hydrogenation suffers from the requirement for separation/purification unit operations to extract the target product. We have examined, for the first time, the continuous gas phase hydrogenation (P = 1 atm; T = 373 K) of primary (3-butyn-1-ol), secondary (3-butyn-2-ol) and tertiary (2-methyl-3-butyn-2-ol) C4 alkynols using a 1.2% wt. Pd/Al2O3 catalyst. Post-TPR, the catalyst exhibited a narrow distribution of Pdδ- (based on XPS) nanoparticles in the size range 1-6 nm (mean size = 3 nm from STEM). Hydrogenation of the primary and secondary alkynols was observed to occur in a stepwise fashion (-C≡C- → -C=C- → -C-C-) while alkanol formation via direct -C≡C- → -C-C- bond transformation was in evidence in the conversion of 2-methyl-3-butyn-2-ol. Ketone formation via double bond migration was promoted to a greater extent in the transformation of secondary (vs. primary) alkynol. Hydrogenation rate increased in the order primary < secondary < tertiary. The selectivity and reactivity trends are accounted for in terms of electronic effects.