ZnO/ionic liquid catalyzed biodiesel production from renewable and waste lipids as feedstocks

A new protocol for biodiesel production is proposed, based on a binary ZnO/TBAI (TBAI = tetrabutylammonium iodide) catalytic system. Zinc oxide acts as a heterogeneous, bifunctional Lewis acid/base catalyst, while TBAI plays the role of phase transfer agent. Being composed by the bulk form powders, the whole catalyst system proved to be easy to use, without requiring nano-structuration or tedious and costly preparation or pre-activation procedures. In addition, due to the amphoteric properties of ZnO, the catalyst can simultaneously promote transesterification and esterification processes, thus becoming applicable to common vegetable oils (e.g., soybean, jatropha, linseed, etc.) and animal fats (lard and fish oil), but also to waste lipids such as cooking oils (WCOs), highly acidic lipids from oil industry processing, and lipid fractions of municipal sewage sludge. Reusability of the catalyst system together with kinetic (Ea) and thermodynamic parameters of activation (∆G‡ and ∆H‡) are also studied for transesterification reaction

Synthesis of Tailored Perfluoro Unsaturated Monomers for Potential Applications in Proton Exchange Membrane Preparation

The aim of the present work is the synthesis and characterization of new perfluorinated monomers bearing, similarly to Nafion®, acidic groups for proton transport for potential and future applications in proton exchange membrane (PEM) fuel cells. To this end, we focused our attention on the synthesis of various molecules with (i) sufficient volatility to be used in vacuum polymerization techniques (e.g., PECVD)), (ii) sulfonic, phosphonic, or carboxylic acid functionalities for proton transport capacity of the resulting membrane, (iii) both aliphatic and aromatic perfluorinated tags to diversify the membrane polarity with respect to Nafion®, and (iv) a double bond to facilitate the polymerization under vacuum giving a preferential way for the chain growth of the polymer. A retrosynthetic approach persuaded us to attempt three main synthetic strategies: (a) organometallic Heck-type cross-coupling, (b) nucleophilic displacement, and (c) Wittig–Horner reaction (carbanion approach). Preliminary results on the plasma deposition of a polymeric film are also presented. The variation of plasma conditions allowed us to point out that the film prepared in the mildest settings (20 W) shows the maximum monomer retention in its structure. In this condition, plasma polymerization likely occurs mainly by rupture of the bond in the monomer molecule

A selective cellulose/hemicellulose green solvents extraction from buckwheat chaff

A two-phase extraction process was adopted to obtain cellulose and hemicellulose from buckwheat chaff by using green solvents. We are proposing a combination of propylene carbonate (PC) and ionic liquids (ILs) in a 1:5 ratio. We compared the first-generation ILs 1-butyl-2,3-dimethylimidazolium chloride (BdmimCl), and 1-butyl-3-methyl imidazolium acetate (BmimAc) with respect to the tetrabutyl ammonium acetate (TBAAc). The cellulose and hemicellulose were, firstly, extracted into the PC/IL mixture and subsequently precipitated by water addition. All precipitate materials were analysed by FTIR-ATR and TGA, while the organic phase and the supernatant after water addition were analysed by using self-diffusion NMR. The PC green co-solvent was proven to be an exceptional candidate to replace dimethyl sulfoxide. The highest amount of precipitate material after water addition was obtained with PC-BmimAc, while PC-TBAAc was showing the highest cellulose/hemicellulose selectivity. Furthermore, a preferential interaction of the supernatant cellulose residue with PC or acetate was observed by self-diffusion NMR

Deep Control of Linear Oligomerization of Glycerol Using Lanthanum Catalyst on Mesoporous Silica Gel

The valorization of glycerol (1), a waste of biodiesel production of Fatty Acid Methyl Esters (FAMEs), adopting a “green” approach, represents an important goal of sustainable chemistry. While the polymerization of 1 to hyperbranched oligomers is a well-established process, the linear analogues are difficult to obtain. In this context, we explore the reaction without the solvent of heterogeneous hybrid La(III)O-KIT-6 catalyst (2), which is based on lanthanum oxide on mesoporous silica gel, showing a superior linear selectivity compared to most of the analogous catalysts recently reported

Catalytic activities of heterogeneous catalysts obtained by copolymerization of metal-containing 2-(acetoacetoxy)ethyl methacrylate

AbstractAmong the synthetic strategies commonly used for supporting a metal complex onto an organic polymer in order to obtain an heterogenous catalyst, a valid choice is to synthesize a metal containing monomer (MCM), which can subsequently be subjected to polymerization with suitable comonomers and crosslinkers, achieving a supported transition metal catalyst as a metal-containing polymer (MCP). In this context, during the last two decades, we explored the use of 2-(acetoacetoxy)ethyl methacrylate (HAAEMA) as a ligand to prepare several MCMs for the relevant MCPs. In this review we summarize and discuss our developments in the studies of the catalytic activity of these "hybrid" catalysts. These catalysts have demonstrated high efficiency and/or excellent selectivity in several kinds of chemical reactions and very often they could be recovered and reused in multiple cycles maintaining their activity and selectivity without suffering from appreciable metal leaching

Green procedure for one-pot synthesis of azelaic acid derivatives using metal catalysis

Background & Objective: A green one-pot synthesis of oleic acid (1) derivatives is promoted by Rare Earth Metal (REM) triflates and commercial Molybdenum dioxo dichloride (MoCl 2 O 2 ) in the presence hydrogen peroxide as a green oxidant. Results: The protocol permits to govern the oxidation selectivity by simply choosing the proper combination of Mo and Sc catalysts. Conclusion: Methyl oleate epoxide 2a and azelaic acid 6 thus obtained are valuable industrial intermediates for synthesizing bio-compostable plastics, plasticizers of PVC, lubricating oils, cosmetics and pharmaceuticals (bactericides, anti-inflammatories, etc.)

Position Paper of the Italian Association of Medical Oncology on Early Palliative Care in Oncology Practice (Simultaneous Care)

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