Vapor pressure curves and isobaric vapor-liquid equilibrium for binary systems with compounds obtained from glycerol to be used as components of a bio-diesel mixture

The search of new renewable fuels and the interest of finding new uses for the abundant subproducts of many industrial processes have prompt Eni S.p.A to develop a technology for producing biofuels from glycerol. One of the compounds involved in this process is 2-ethyl-4-ethoxymethyl-1,3-dioxolane (PrEDO). In this paper their temperature - vapor pressure curve has been determined experimentally as well as binary vapor-liquid equilibrium data at different pressures of systems where this compound is involved. The experimental vapor pressure data of PrEDO have been fitted with the Antoine equation. The vapor liquid equilibrium data have been correlated and calculated with UNIFAC, UNIQUAC, NRTL and Wilson to analyze their use when designing distillation processes.Eni S.p.A. is gratefully acknowledged for the financial support

Influence of pH on the kinetics of hydrolysis reactions: the case of epichlorohydrin and glycidol

Glycidol (GL) and epichlorohydrin (EPI) are two widely used molecules in chemical, pharmaceutical and food industry applications. However, their use in aqueous environments causes the formation of compounds, like monochloropropanediol (MCPD) and dichloropropanol (DCP), reported as dangerous for human health and therefore regulated by severe law restrictions. To identify the conditions leading to such species and design the corresponding processes in order to prevent their formation, hydrolysis and chlorination of EPI and GL, together with dehydrohalogenation of DCP and MCPD, have been systematically analysed. Different reaction conditions in terms of temperature, pH and chloride ion concentration have been experimentally investigated and the concentration of the involved species was tracked over time by gas chromatography and high-performance liquid chromatography. These experimental data were fitted through a kinetic model, which allowed a general expression of the observed rate constant of each reaction as a function of temperature and pH to be quantified. In particular, the reaction rates are conveniently expressed as combinations of three contributions: alkaline, neutral and acid. The corresponding rate laws explicitly account for the critical role of pH. The developed mechanistic model exhibits good prediction ability and may represent the basis for optimising processes employing EPI and GL

Alkylation of methyl linoleate with propene in ionic liquids in the presence of metal salts

Vegetable oils and fatty acid esters are suitable precursor molecules for the production of a variety of bio-based products and materials, such as paints and coatings, plastics, soaps, lubricants, cosmetics, pharmaceuticals, printing inks, surfactants, and biofuels. Here, we report the possibility of using Lewis acidic ionic liquids (ILs) to obtain polyunsaturated ester dimerization-oligomerization and/or, in the presence of another terminal alkene (propene), co-polymerization. In particular, we have tested the Lewis acidic mixtures arising from the addition of a proper amount of GaCl3 (X > 0.5) to two chloride-based (1-butyl-3-methylimidazolium chloride, [bmim]Cl, and 1-butylisoquinolium chloride, [BuIsoq]Cl) or by dissolution of a smaller amount of Al(Tf2N)3 (X = 0.1) in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [bmim][Tf2N]. On the basis of product distribution studies, [bmim][Tf2N]/Al(Tf2N)3 appears the most suitable medium in which methyl linoleate alkylation with propene can compete with methyl linoleate or propene oligomerization

Regulatory T cell frequency in patients with melanoma with different disease stage and course, and modulating effects of high-dose interferon-α 2b treatment

<p>Abstract</p> <p>Background</p> <p>High-dose interferon-alpha 2b (IFN-α 2b) is the only approved systemic therapy in the United States for the adjuvant treatment of melanoma. The study objective was to explore the immunomodulatory mechanism of action for IFN-α 2b by measuring serum regulatory T cell (Treg), serum transforming growth factor-β (TGF-β), interleukin (IL)-10, and autoantibody levels in patients with melanoma treated with the induction phase of the high-dose IFN-α 2b regimen.</p> <p>Methods</p> <p>Patients with melanoma received IFN-α 2b administered intravenously (20 MU/m²each day from day 1 to day 5 for 4 consecutive weeks). Serum Treg levels were measured as whole lymphocytes in CD4⁺cells using flow cytometry while TGF-β, IL-10, and autoantibody levels were measured using enzyme-linked immunosorbent assays.</p> <p>Results</p> <p>Twenty-two patients with melanoma received IFN-α 2b treatment and were evaluated for Treg levels. Before treatment, Treg levels were significantly higher in patients with melanoma when compared with data from 20 healthy subjects (<it>P </it>= 0.001; Mann-Whitney test). Although a trend for reduction of Treg levels following IFN-α 2b treatment was observed (average decrease 0.29% per week), statistical significance was not achieved. Subgroup analyses indicated higher baseline Treg levels for stage III versus IV disease (<it>P </it>= 0.082), early recurrence versus no recurrence (<it>P </it>= 0.017), deceased versus surviving patients (<it>P = </it>0.021), and preoperative neoadjuvant versus postoperative adjuvant treatment groups (not significant). No significant effects were observed on the levels of TGF-β, IL-10, and autoantibodies in patients with melanoma treated with IFN-α 2b.</p> <p>Conclusions</p> <p>Patients with melanoma in this study showed increased basal levels of Treg that may be relevant to their disease and its progression. Treg levels shifted in patients with melanoma treated with IFN-α 2b, although no firm conclusions regarding the role of Tregs as a marker of treatment response or outcome can be made at present.</p

Vapor-liquid equilibrium of 3-ethoxy-1,2-propanediol + water/ethanol/diethyl ether/glycerol/1,2-propanediol at different pressures

The large availability of glycerol on the market and EU directives in the field of automotive fuels prompt Eni S.p.A to develop a technology for producing biofuels from glycerol. This work focuses on determining isobaric vapor-liquid equilibrium data at different pressures of binary systems constituted by 3-ethoxy-1,2-propanediol, an intermediate product, and some of the other compounds involved in the reactions: water, ethanol, 1,2-propanediol, diethyl ether and glycerol. Moreover, the vapor pressure curve of 3-ethoxy-1,2-propanediol was determined at different temperatures. Finally, different thermodynamic models (UNIFAC, UNIQUAC, NRTL and Wilson), were tested against the experimental data to analyze their possible use when designing separation processes of 3-ethoxy-1,2-propanediol.Eni SpA is gratefully acknowledged for the financial support

Decalin ring opening over NiWS/SiO2-Al2O3 catalysts in the presence of H2S

SSCI-VIDE+ECI2D+LDF:NCY:LPI:DLA:EBL:ELE:CGEInternational audienceSelective ring opening (SRO) is an attractive route for increasing the cetane number of diesel fuels. Noble metal-based catalysts have beenproposed for this purpose. However, considering the type of processesproducing diesel, more sulfur-resistant catalysts would be preferred forSRO. In the present study, we investigated the performance ofbifunctional NiW sulfide catalysts supported onto amorphous silicaalumina in gas-phase decalin hydroconversion at high hydrogen pressure(5 MPa) in the presence of 0.8% H2S concentration at 350-380 degrees C.Two-dimensional gas chromatography (GC x GC) was extensively employed toidentify the reaction products and determine their distributions in theform of chemical families. The impact of acidity due to two differentSiO2 contents (40 and 70 wt.%) in the support, as well as promoting thecatalytic systems by P or F doping, were studied on the one hand. On theother hand, the improvement of the hydrogenation function by the use ofchelating agents was investigated. Up to 17% in selectivity toring-opening products was obtained. The reaction mechanism is shown tobe mostly governed by the acidic function, which promotes the formationof skeletal-isomerization products, while the sulfide phase allowshydrogen activation. (C) 2015 Elsevier B.V. All rights reserved

Effect of H 2 S on the mechanisms of naphthene ring opening and isomerization over Ir/NaY: A comparative study of decalin, perhydroindan and butylcyclohexane hydroconversions

International audienc

Understanding the mechanisms of decalin hydroprocessing using comprehensive two-dimensional chromatography

International audienceComprehensive two-dimensional gas chromatography (GC × GC) is a powerful technique for analyzing mixtures of hundreds of hydrocarbons. In the context of fuel upgrading through selective ring opening, we propose a methodology for GC × GC analysis of complex mixtures resulting from the hydroprocessing of a single model gas oil compound, decalin, over two different types of bifunctional catalysts based on a transition-metal sulfide (NiWS on amorphous silica–alumina) or a noble metal (Ir on La,Na–Y zeolite). The reactions lead to several products families, the dominant ones being ring-opening products (ROPs) and skeletal-isomerization products (SkIPs). First, it is shown that the ROP distribution can be characterized in terms of isomerization degree by using the cumulative distribution function of the GC × GC (GC Image) software. Second, in a more quantitative approach, the products families have been subdivided into chemical groups, according to the isomerization degrees of the individual compounds, which were almost all tentatively identified by two-dimensional gas chromatography coupled with mass spectrometry (GC × GC-MS) through the use of literature data. This allows us to thoroughly analyze the influence of the catalyst nature and the presence of H2S in the reactant feed on the products distribution, and thereby gain insight into the mechanism of decalin hydroconversion over bifunctional catalysts. In particular, it is shown that metal sulfidation suppresses the metal-catalyzed C–C hydrogenolysis pathway at the benefit of undesirable acid-catalyzed isomerization steps. The methodologic work presented here for decalin is believed to be applicable to other bicyclic (naphthenic or aromatic) compounds