RAMIS G.

The F.t.i.r. spectra of isobutene adsorbed at 170-300 K on the pure oxides silica, alumina, magnesia and titania, as well as on the phosphated samples prepared by impregnation of these pure oxides and of silica-alumina with phosphoric acid have been recorded. At low temperatures (170-220 K), molecularly adsorbed species are observed on pure...

No description

The adsorption of nitric oxide, nitrogen dioxide and ammonia and their coadsorption on vanadia-titania have been studied by FT-IR spectroscopy. Upon nitric oxide adsorption, a surface nitrosyl species is formed rapidly and nitrates are formed slowly by oxidation. Nitrogen dioxide adsorption forms nitrate species by oxidation and nitric oxide....

The economic sustainability of renewable based sources is a matter of debate and the technology is changing very fast. We here considered three examples of exploitation of bioethanol as renewable source: a) centralised hydrogen prodution; b) heat and power cogeneration (residential scale); c) ethylene production. Bioethanol can be a suitable...

The production of hydrogen through photoreforming of aqueous solutions of organic compounds is considered as a way to exploit solar energy storage in the form of hydrogen. The photocatalytic reforming can be promoted by a photocatalyst, optimally a solid semiconductor able to absorb the major quota of solar energy. In this work, glucose was...

The photoreforming of glucose has been studied over TiO2 photocatalyst with different photoreactors, focusing on the effect of the reaction conditions: temperature, pressure, catalyst and substrate concentration. The effect of pressure was particularly significant, decreasing hydrogen evolution rate, but improving the conversion of the...

The FT-IR spectra of ethylene molecularly adsorbed on some oxidic surfaces at low temperature are presented and discussed both in terms of vibrational frequencies and of band intensities. A hydrogen-bonding interaction is observed between ethylene and surfaces having active hydroxy groups, like amorphous silica and HY zeolite. Strong adsorption...

The deposition of V-based catalysts for the oxidative dehydrogenation of propane to propene on cordierite honeycomb monoliths was optimised as a strategy to decrease the contact time in a structured reactor with respect to a conventional fixed bed one. 10 wt% VOx supported over SiO2 or Al2O3 were used as catalysts, deposed over the monolith...

Photocatalytic processes are acquiring increasing attention as a means to exploit solar energy to promote chemical transformations. Reactor design and modelling is a fundamental step to set the basis for the possible scale up of the technology. To this purpose, we have modelled the radiation flow depending on reactor geometry for different...

Photocatalytic processes are acquiring increasing attention as a mean to exploit solar energy in promoting chemical transformations. Numerous applications can be found in the literature on the use of semiconductors for water treatment or to produce renewable fuels. Very challenging applications combine also the two concepts. These topics are...

Solar irradiation data collected at the latitude of Milan city, near the 45th parallel North, and original activity data of some high-performing photocatalysts (i.e., commercial TiO2 P25, TiO2 prepared by flame spray pyrolysis, 0.2% wt/wt Au/P25) have been used to evaluate the feasibility and the efficiency of an ideal solar photoreactor for...

The continuous-flow production of active pharmaceutical ingredients is a spreading applicative research field. Process simulation tools are effective means for in silico process design, but care is needed. A paradigmatic example is the synthesis of ibuprofen. First, the most appropriate thermodynamic models must be selected. The rich databases...

Photocatalysis has been used to reduce nitrate ions from waste and drinking water. A semibatch photoreactor was developed for this process and commercial nanostructured TiO2 (P25) and TiO2 in nanosized form prepared by flame spray pyrolysis (FSP) were used as catalysts. Several noble metals were added as co-catalyst on both titania samples and...

The physico-chemical characteristics and the reactivity of sub-monolayer V2O5-WO3/TiO2 deNOx catalysts is investigated in this work by EPR, FT-IR and reactivity tests under transient conditions. EPR indicates that tetravalent vanadium ions both in magnetically isolated form and in clustered, magnetically interacting form are present over the...

The physico-chemical characteristics and the reactivity of sub-monolayer V2O5-WO3/TiO2 deNOx catalysts is investigated in this work by EPR, FT-IR and reactivity tests under transient conditions. EPR indicates that tetravalent vanadium ions both in magnetically isolated form and in clustered, magnetically interacting form are present over the...

The possibility to exploit renewable sources for the production of bulk chemicals is attractive and bio-ethanol has been recently proposed as platform to produce hydrogen via steam reforming and bio-ethylene by dehydration. Another compound with huge industrial applications is ethylene oxide, which may be in principle obtained in two steps...

The salting out of acetonitrile from water in the presence of ammonium bicarbonate was studied at atmospheric pressure from 4 to 35 °C. The coexisting phases were analyzed independently with H1 nuclear magnetic resonance, ion chromatography, calorimetry, and titrations. The binodal region was described with semiempirical functions and with the...