Marco Di Girolamo

Selective synthesis of isobutanol by means of the Guerbet reaction: Part 2: Reaction of methanol/ethanol and methanol/ethanol/n-propanol mixtures over copper based/MeONa catalytic systems

The synthesis of isobutanol via the Guerbet condensation between methanol and ethanol was studied by using sodium methoxide (MeONa) as soluble basic component and copper-based catalysts as heterogeneous dehydrogenating/hydrogenating metal species. The effect of the nature of the catalyst and the relative amount of its individual components with respect to the reacting alcohols as well as of temperature on productivity and selectivity of the process was investigated. The collected data indicated that the copper chromite/MeONa was more active than Cu-Raney/MeONa system. The reaction was shown to proceed with the formation only of n-propanol and isobutanol. Ethanol conversion up to 61% with selectivity to isobutanol up to 98.4% was obtained. The same catalytic systems were also employed in the reaction of the methanol/ethanol/n-propanol ternary mixture. Again copper chromite/MeONa resulted more active than the Cu-Raney/MeONa system. Finally, experiments were carried out on methanol/n-propanol mixtures in the presence of the copper chromite/MeONa catalytic system by recycling both the recovered solid copper component and the liquid reaction mixture for evidencing eventual copper leaching by MeONa. On the basis of the obtained results it was concluded that in the Guerbet reaction copper chromite works as heterogeneous catalyst.

Light olefins dimerization to high quality gasoline components

Abstract New attractive technologies can be designed in the field of light olefins dimerization (C3–C5) in order to obtain products useful as gasoline blending components; the technologies are characterized both by low investment costs and by high product quality. Isobutene dimerization is a powerful alternative to MTBE production whenever the use of the latter will be forbidden in gasoline. Also the dimerization of iso-amylenes and propylene, when properly designed, can give products (both the olefins and the corresponding hydrogenated derivatives) characterized by very high octane numbers. More in general all these technologies can help to debottleneck the FCC downstream when enhanced olefins production is achieved by means of new FCC catalysts and processes.

Acidic and basic ion exchange resins for industrial applications

Abstract Ion exchange resins, particularly the macroporous variety, are very versatile catalysts, which play a more and more important role in the large scale manufacture of petrochemicals and solvents. Different acid and basic resins have been studied for several reactions in order to improve the catalytic performances and the process engineering with respect to current technology. Strongly basic resins were checked as catalysts for the methanol carbonylation to methyl formate. Strongly acid resins were instead employed in the isobutene dimerization to produce a mixture of ether and branched hydrocarbons, mainly C8, with high octane number.

Synthesis of isobutanol by the Guerbet condensation of methanol with n-propanol in the presence of heterogeneous and homogeneous palladium-based catalytic systems

AbstractThe catalytic synthesis of isobutanol ( i BuOH), via the Guerbet condensation of methanol with n-propanol is described.In particular, bifunctional catalysts based on either heterogeneous or homogeneous dehydrogenating/hydrogenating pal-ladium species and on sodium methoxide (MeONa) as basic component were investigated. When heterogeneous Pd/Cand MeONa was used as catalytic system a high activity was obtained with turnover numbers up to about 110mol of i BuOH/(mol of Pdh). The increase of the MeONa/Pd molar ratio increased the activity of the catalyst. However, differentlyfrom Cu-based/MeONa catalysts, a significant metal leaching was observed; recycle experiments indicated that both hetero-geneous and homogeneous palladium species are involved in the catalysis. When homogeneous palladium complexes, such astetrakis(triphenylphosphine)palladium(0) [Pd(PPh 3 ) 4 ], diphenylphosphinoethane(dichloro)palladium(II) [Pd(dppe)Cl 2 ] andbis(dibenzylideneacetone)palladium(0) [Pd(dba) 2 ], were used in combination with MeONa a remarkable activity was alsoobtained, independently of the oxidation state of the palladium precursor. During the reaction deposition of a solid was ob-served and recycle experiments carried out both on the recovered solid and on the liquid phase suggested that also in this casethe activity has to be addressed to both heterogeneous and homogeneous (or colloidal) palladium species.© 2003 Elsevier Science B.V. All rights reserved.

Methanol carbonylation to methyl formate catalyzed by strongly basic resins

The liquid phase methanol carbonylation to methyl formate has been investigated both with homogeneous sodium methoxide, the industrial catalyst for this process, and with heterogeneous strongly basic resins. The strongly basic resins Amberlyst A26 and Amberlite IRA 400 displayed a higher activity than sodium methoxide. The activation procedure and the dependence of the reaction rate on CO pressure have also been investigated.

Engineering Alkanes to Olefins and Higher Value Chemicals

Olefins are the building blocks of choice for manufacturing a huge amount of commodities and specialties. A network of technologies connects the fossil raw materials (crude oil, Natural Gas, condensates etc.) with the olefins and the final products. The basic concepts of these technologies are reported, together with the expected trends in their evolution.