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Aresta M.,National University of Singapore | Aresta M.,Consorzio Interuniversitario Reattivita Chimica e Catalisi | Dibenedetto A.,Consorzio Interuniversitario Reattivita Chimica e Catalisi | Dibenedetto A.,University of Bari
Journal of the Brazilian Chemical Society | Year: 2014

The need for a better carbon management and the reduction of CO2 emissions push away from the linear-carbon economy (LCE) towards a better carbon management including carbon recycling (CR). This implies the utilization of gaseous and liquid process streams so far under-utilized, and often either sent to combustion or disposed of. In this paper, four cases are discussed, namely: low-alkane streams, industrial CO2, ligno-cellulosic waste and salty-watery-glycerol. The role of catalysis in the valorization of such C-sources is discussed and examples of innovative processes are presented. ©2014 Sociedade Brasileira de Química.


Dibenedetto A.,University of Bari | Dibenedetto A.,Consorzio Interuniversitario Reattivita Chimica e Catalisi | Colucci A.,Consorzio Interuniversitario Reattivita Chimica e Catalisi | Aresta M.,National University of Singapore
Environmental Science and Pollution Research | Year: 2016

In the present work, microalgae strains, such as Scenedesmus obliquus and Phaeodactylum tricornutum grown in indoor/outdoor photobioreactors (PBRs) and in open ponds (this is the first study on such strains cultivated in the local Southern Italy climatic conditions), were fully analyzed for their protein content, carbohydrates, lipids, and fatty acid profile in order to assess their potential use for the production of biofuels, chemicals, and omega-3, and as animal feed and human food. They are compared with Nannochloropsis sp. (commercial sample) which was fully analyzed in our laboratory and Chlorella (literature data). An economic evaluation was carried out, demonstrating that the cultivation of microalgae for the production of only biofuels will not match the economic standards. Conversely, if chemicals are also produced applying the biorefinery concept and using wastewater as a source of nutrients, it will be possible to have a good positive return from microalgae. © 2016 Springer-Verlag Berlin Heidelberg


PubMed | National University of Singapore, Consorzio Interuniversitario Reattivita Chimica e Catalisi and University of Bari
Type: Journal Article | Journal: Environmental science and pollution research international | Year: 2016

In the present work, microalgae strains, such as Scenedesmus obliquus and Phaeodactylum tricornutum grown in indoor/outdoor photobioreactors (PBRs) and in open ponds (this is the first study on such strains cultivated in the local Southern Italy climatic conditions), were fully analyzed for their protein content, carbohydrates, lipids, and fatty acid profile in order to assess their potential use for the production of biofuels, chemicals, and omega-3, and as animal feed and human food. They are compared with Nannochloropsis sp. (commercial sample) which was fully analyzed in our laboratory and Chlorella (literature data). An economic evaluation was carried out, demonstrating that the cultivation of microalgae for the production of only biofuels will not match the economic standards. Conversely, if chemicals are also produced applying the biorefinery concept and using wastewater as a source of nutrients, it will be possible to have a good positive return from microalgae.


Lee J.G.,Korea University | Kim D.-Y.,Korea University | Lee J.-H.,Korea University | Kim M.-W.,Korea University | And 7 more authors.
ACS Applied Materials and Interfaces | Year: 2016

We demonstrate production of nanotextured p-type cupric oxide (CuO) films via a low-cost scalable supersonic cold spray method in open air conditions. Simply sweeping the spray nozzle across a substrate produced a large-scale CuO film. When used as hydrogen evolution photocathodes, these films produced photocurrent densities (PCD) of up to 3.1 mA/cm2 under AM1.5 illumination, without the use of a cocatalyst or any additional heterojunction layers. Cu2O particles were supersonically sprayed onto an indium tin oxide (ITO) coated soda lime glass (SLG) substrate, without any solvent or binder. Annealing in air converted the Cu2O films to CuO, with a corresponding decrease in the bandgap and increase in the fraction of the solar spectrum absorbed. Annealing at 600 °C maximized the PCD. Increasing the supersonic gas velocity from ∼450 to ∼700 m/s produced denser films with greater surface roughness, in turn producing higher PCD. The nanoscale texture of the films, which resembles the skin of a dinosaur, enhanced their performance, leading to one of the highest PCD values in the literature. We characterized the films by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy, scanning electron microscopy, and transmission electron microscopy to elucidate the origins of their outstanding performance. This supersonic cold spraying deposition has the potential to be used on a commercial scale for low cost mass production. © 2016 American Chemical Society.


Aresta M.,Consorzio Interuniversitario Reattivita Chimica e Catalisi | Acquaviva M.I.,CNR Institute of Neuroscience | Baruzzi F.,CNR Institute of Sciences of Food Production | Noce R.M.L.,CNR Institute of Neuroscience | And 4 more authors.
World Journal of Microbiology and Biotechnology | Year: 2010

In this study 28 bacterial strains, isolated from greenwaters-polluted-soil, were investigated for their ability to grow in presence of phenols added to Mineral Basal Medium (MBM) in aerobic conditions. In particular, three of them were found to be able to use as sole carbon source phenol, cathecol, caffeic acid and ferulic acid with efficiency ranging from 76% (phenol in 5 days, millimolar concentration from 3.7 10-2 to 9 10-3) to 95% (ferulic acid in 2 days millimolar concentration from 6.8 10-1 to 3 10-2). For these strains the taxonomic position was studied by amplification and sequencing of 16S rRNA genes. The isolated strains were classified belonging to Arthrobacter sulfureus, Pseudomonas synxantha and Pseudomonas oryzihabitans. Noteworthy, for the first time such Pseudomonas strains have been shown to be able to use polyphenols as the only carbon source in vitro. In fact, to the best of our knowledge, this kind of study were not done on Ps. Synxantha, while it was recently shown the ability of P. oryzihabitans to degrade catechol. These findings may open to new biotechnological applications for the degradation of polyphenols. © 2009 Springer Science+Business Media B.V.


Rosi L.,University of Florence | Rosi L.,Consorzio Interuniversitario Reattivita Chimica e Catalisi | Bartoli M.,University of Florence | Undri A.,University of Florence | And 3 more authors.
Journal of Molecular Catalysis A: Chemical | Year: 2015

Dianols (etherified derivatives of bis-phenol-A) and bis-phenol-A (BPA) itself were efficiently obtained from waste polycarbonate (PC) via a fast catalytic hydrolysis/glycolysis process using microwave heating. A complete conversion of waste PC was achieved using a microwave power of 3 kW in a very short time (10 min). A mixture of BPA, mono- and dianols were obtained working with a basic catalyst and ethylene glycol as solvent. This mixture was selectively converted into dianol 220 (2,2′-((propane-2,2-diylbis(4,1-phenylene))bis(oxy))bis (ethan-1-ol)) using diethyl carbonate. Furthermore several dianols were obtained through a more eco-friendly process through hydrolysis in the appropiate diol as solvent and Na2CO3 as catalyst followed by a one-pot etherification with urea, zinc oxide and a microwave heating for 15 min. On the contrary using THF/H2O as solvent and KOH as catalyst, PC was hydrolysed to BPA with high selectivity (80.6, wt%). © 2015 Elsevier B.V. All rights reserved.


Rossi R.,University of Pisa | Lessi M.,University of Pisa | Lessi M.,Consorzio Interuniversitario Reattivita Chimica e Catalisi | Manzini C.,University of Pisa | And 3 more authors.
Synthesis (Germany) | Year: 2016

The significant number of papers and reviews published in this last decade testifies to the utility of the transition-metal-catalyzed direct C-H (hetero)arylation reactions of (hetero)arenes as efficient and powerful tools for the step- and atom-economical, regio- and chemoselective synthesis of natural and unnatural compounds. However, no review has so far been devoted to summarizing the application of these reactions in the synthesis of biologically active compounds. This review with 341 references aims to fill this gap, providing a comprehensive picture of the transition-metal-catalyzed intra- and intermolecular direct C-H (hetero)arylation reactions of (hetero)arenes with (hetero)aryl halides or pseudohalides that have been used as key steps of syntheses of unnatural biologically relevant compounds including pharmaceutical targets, up to the end of September 2015. Attention has also been directed to provide a brief description of the biological properties of the synthesized compounds. 1 Introduction 2 Syntheses via Intramolecular Direct (Hetero)arylation of (Hetero)arene Derivatives 3 Syntheses via Intermolecular Direct (Hetero)arylation Reactions 3.1 Of Arenes 3.2 Of Five-Membered Heteroarenes with One Heteroatom 3.3 Of Five-Membered Heteroarenes with Two Heteroatoms 3.4 Of Five-Membered Heteroarenes with Three and Four Heteroatoms 3.5 Of Five-Membered Heteroarenes Fused to a Six-Membered Heteroarene 3.6 Of Five-Membered Heteroarene Moieties of Tricyclic Heteroarenes 3.7 Of Six-Membered Heteroarenes 4 Syntheses of Nitrogen-Containing Polycyclic Heteroarene via One-Pot Palladium-Catalyzed Domino Direct Arylation/N-Arylation Reactions 5 Conclusions. © 2016 Georg Thieme Verlag Stuttgart New York.


Pavarelli G.,University of Bologna | Velasquez Ochoa J.,University of Bologna | Caldarelli A.,University of Bologna | Puzzo F.,University of Bologna | And 3 more authors.
ChemSusChem | Year: 2015

We investigated the synthesis of maleic anhydride by oxidehydration of a bio-alcohol, 1-butanol, as a possible alternative to the classical process of n-butane oxidation. A vanadyl pyrophosphate catalyst was used to explore the one-pot reaction, which involved two sequential steps: 1)1-butanol dehydration to 1-butene, catalysed by acid sites, and 2)the oxidation of butenes to maleic anhydride, catalysed by redox sites. A non-negligible amount of phthalic anhydride was also formed. The effect of different experimental parameters was investigated with chemically sourced 1-butanol, and the results were then confirmed by using genuinely bio-sourced 1-butanol. In the case of bio-1-butanol, however, the purity of the product remarkably affected the yield of maleic anhydride. It was found that the reaction mechanism includes the oxidation of butenes to crotonaldehyde and the oxidation of the latter to either furan or maleic acid, both of which are transformed to produce maleic anhydride. MA and PA together: Maleic anhydride (MA) can be produced by the one-pot oxidehydration of bio-1-butanol with a vanadyl pyrophosphate catalyst. The reaction mechanism includes the oxidation of butenes to crotonaldehyde and the oxidation of the latter to either furan or maleic acid, both of which are transformed to produce maleic anhydride. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA.


Zardi P.,University of Milan | Pozzoli A.,University of Milan | Pozzoli A.,Consorzio Interuniversitario Reattivita Chimica e Catalisi | Pozzoli A.,Liverpool John Moores University | And 4 more authors.
Dalton Transactions | Year: 2015

A mechanism for the aziridination of olefins by aryl azides (ArN3), promoted by ruthenium(ii) porphyrin complexes, is proposed on the basis of kinetic and theoretical studies. All the recorded data support the involvement of a mono-imido ruthenium complex as the active intermediate in the transfer of the nitrene moiety "ArN" to the olefin. The selectivity of the aziridination vs. the uncatalysed triazoline formation can be enhanced by fine-tuning the electronic features of the porphyrin ligand and the olefin/azide catalytic ratio. The DFT study highlights the importance of an accessible triplet ground state of the intermediate ruthenium mono-imido complex to allow the evolution of the aziridination process. © The Royal Society of Chemistry 2015.


Quaranta E.,University of Bari | Quaranta E.,Centro Interdipartimentale Of Ricerca Su Metodologie E Tecnologie Ambientali Metea | Quaranta E.,Consorzio Interuniversitario Reattivita Chimica e Catalisi | Angelini A.,Consorzio Interuniversitario Reattivita Chimica e Catalisi | And 3 more authors.
ACS Catalysis | Year: 2014

Polymer-bound DBU (PS-DBU, DBU = 1,8-diazabicyclo[5.4.0]undec-7-ene) is an effective and selective catalyst for solventless N-phenoxycarbonylation of N-heteroaromatics (pyrrole (1), indole (2), and carbazole (3)) with diphenyl carbonate (DPC), used as an eco-friendly active carbonyl species in place of phosgene-derivatives. The immobilized catalyst is less active than unsupported DBU but can be recovered easily at the end of catalytic run and recycled effectively. Dedicated studies have demonstrated that DBU can react as a nucleophile with DPC even when it is anchored on the polymeric matrix, and provided the first direct evidence (FTIR and solid-state 13C NMR) of formation of a 8-carboxy-substituted 1,8-diazabicyclo[5.4.0]undec-7-enium cation in DBU-promoted nucleophilic activation of carbonic acid diesters. © 2013 American Chemical Society.

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