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Chiche D.,French Institute of Petroleum | Diverchy C.,Total Research and Technology Feluy | Lucquin A.-C.,French Institute of Petroleum | Porcheron F.,French Institute of Petroleum | Defoort F.,CEA Grenoble
Oil and Gas Science and Technology | Year: 2013

Tropsch (FT) based B-XTL processes are attractive alternatives for future energy production. These processes aim at converting lignocellulosic biomass possibly in co-processing with petcoke, coal, or vacuum residues into synthetic biofuels. A gasification step converts the feed into a synthesis gas (CO and H2 mixture), which undergoes the Fischer-Tropsch reaction after H2/CO ratio adjustment and CO2 removal. However synthesis gas also contains various impurities that must be removed in order to prevent Fischer-Tropsch catalyst poisoning. Due to the large feedstocks variety that can be processed, significant variations of the composition of the synthesis gas are expected. Especially, this affects the nature of the impurities that are present (element, speciation), as well as their relative contents. Moreover, due to high FT catalyst sensitivity, severe syngas specifications regarding its purity are required. For these reasons, synthesis gas purification constitutes a major challenge for the development of B-XTL processes. In this article, we focus on these major hurdles that have to be overcome. The different kinds of syngas impurities are presented. The influence of the nature of feedstocks, gasification technology and operating conditions on the type and content of impurities is discussed. Highlight is given on the fate of sulfur compounds, nitrogen compounds, halides, transition and heavy metals. Main synthesis gas purification technologies (based on adsorption, absorption, catalytic reactions, etc.) are finally described, as well as the related challenges. © 2013, IFP Energies nouvelles.

Di Lorenzo M.L.,CNR Institute of Chemistry and Technology of Polymers | Rubino P.,CNR Institute of Chemistry and Technology of Polymers | Luijkx R.,Total Research and Technology Feluy | Helou M.,Total Research and Technology Feluy
Colloid and Polymer Science | Year: 2014

The influence of chain structure on crystal polymorphism of poly(lactic acid) (PLA) with high l-lactic acid content (97.8-100 %) is detailed in this contribution. Upon usual processing conditions of PLA, only α and α′ crystals grow, which makes these two polymorphs of major interest for research. The two crystal modifications have similar chain packing, which complicates their quantitative analysis by diffraction methods. The two crystal modifications are instead easily identified by analysis of the crystallization kinetics, which varies not only with temperature, but also with crystal polymorphism. The dependence of the rate of ordering on temperature shows two distinct maxima around 105-110 and 120-125 °C, which are related to growth of α′ and α crystals, respectively. Addition of d-lactic acid co-units leads to a decrease of the overall crystallization rate of PLA, as well as of the rate of spherulite growth (G) of both the crystal modifications. The relative crystallization rates of α and α′ forms are highly affected by stereoregularity, especially in the PLA grades that have a high crystallization rate. A high d-lactic acid content results not only in an overall slower crystal growth, but also in a varied temperature range where each of the two crystal modifications prevail, with a shift to lower temperatures of both the maxima of the G vs. temperature plots, indicating that inclusion of d-lactic acid units in the PLA chain affects crystallization rate of both α and α′ crystal modifications. © 2013 Springer-Verlag.

Barrere C.,University of Rouen | Selmi W.,University of Rouen | Hubert-Roux M.,University of Rouen | Coupin T.,Total Research and Technology Feluy | And 3 more authors.
Polymer Chemistry | Year: 2014

In this work ion mobility-mass spectrometry (IM-MS) coupled to an atmospheric solid analysis probe (ASAP) was used for the characterization of polymer blends involving biodegradable polymers (poly(lactic acid) (PLA), poly(butylene succinate) (PBS)) and poly(ethylene) (PE). Interestingly both PLA and PBS yielded by ASAP an ionization ion series corresponding to cyclic oligomers that were nearly identical to those obtained by conventional Py-GC-CI/MS. However from the drift-time vs. m/z plot of a PLA-PE blend, the ion series of both polymers can be readily identified, as the PLA ions are significantly more compact than the PE ions. From this 2D plot specific mass spectra can be extracted which are almost identical to those of each polymer alone. This work highlights the potential of ASAP-IM-MS to achieve a very fast analysis of complex polymer blends. It was demonstrated that coupling gas phase ion separations (IM) with direct and weakly discriminant ionization techniques (ASAP) significantly enhances the dynamic range of accessible concentrations and polymer polarities, opening a new avenue to carry out more complex "materiomics" studies. © the Partner Organisations 2014.

Martin O.,ETH Zurich | Mondelli C.,ETH Zurich | Cervellino A.,Paul Scherrer Institute | Ferri D.,Paul Scherrer Institute | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2016

Optimal amounts of CO2 are added to syngas to boost the methanol synthesis rate on Cu-ZnO-Al2O3 in the industrial process. The reason for CO2 promotion is not sufficiently understood at the particle level due to the catalyst complexity and the high demands of characterization under true reaction conditions. Herein, we applied operando synchrotron X-ray powder diffraction and modulated-excitation infrared spectroscopy on a commercial catalyst to gain insights into its morphology and surface chemistry. These studies unveiled that Cu and ZnO agglomerate and ZnO particles flatten under CO/H2 and/or CO2/H2. Under the optimal CO/CO2/H2 mixture, sintering is prevented and ZnO crystals adopt an elongated shape due to the minimal presence of the H2O byproduct, enhancing the water-gas shift activity and thus the methanol production. Our results provide a rationale to the CO2 promotion emphasizing the importance of advanced analytical methods to establish structure-performance relations in heterogeneous catalysis. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Martin O.,ETH Zurich | Mondelli C.,ETH Zurich | Curulla-Ferre D.,Total Research and Technology Feluy | Drouilly C.,Total Research and Technology Feluy | And 2 more authors.
ACS Catalysis | Year: 2015

In this study, we gathered further understanding of the function of the components in the Cu-ZnO-Al2O3 catalyst for methanol synthesis from mixed syngas feeds (CO/CO2/H2) to rationally develop systems displaying superior performance. In order to unravel the role of ZnO in the hydrogenation of the preferred methanol source, CO2, and in the (reverse) water-gas shift ((R)WGS) reaction, we tested coprecipitated materials with variable surface zinc content under industrially relevant conditions (5.0 MPa, 503-543 K). We found that a surface enrichment in zinc leads to higher activity and selectivity due to (i) the enhancement of the unique synergistic Cu-ZnO interactions boosting CO2 hydrogenation, (ii) the inhibition of the RWGS reaction which produces the undesired CO, and (iii) the electronic stabilization of the Cu sites against reoxidation by CO2 or H2O. Thus, a catalyst with a surface Zn/(Cu + Zn) ratio of 0.8 displayed superior catalytic properties than a commercial benchmark sample, which featured only half of the ratio. An even more performing catalyst was obtained utilizing oxalates instead of hydroxycarbonates as precursors. The better thermal degradation of the former minimizes the content of residual carbon on the surface of the activated catalyst improving the amount of Cu-ZnO contacts. The retention of the metallic state of copper was greatly favored by the deposition of an electron-withdrawing metal such as gold. The Cu-based activity in mixed syngas and CO2 hydrogenation of the zinc-rich gold-promoted catalyst was ca. 2 and 4 times higher, respectively, than that of the commercial system. © 2015 American Chemical Society.

Cicmil D.,University Utrecht | Meeuwissen J.,Total Research and Technology Feluy | Vantomme A.,Total Research and Technology Feluy | Wang J.,Canadian Light Source Inc. | And 4 more authors.
Angewandte Chemie - International Edition | Year: 2015

A triethylaluminium(TEAl)-modified Phillips ethylene polymerisation Cr/Ti/SiO2 catalyst has been developed with two distinct active regions positioned respectively in the inner core and outer shell of the catalyst particle. DRIFTS, EPR, UV-Vis-NIR DRS, STXM, SEM-EDX and GPC-IR studies revealed that the catalyst produces simultaneously two different polymers, i.e., low molecular weight linear-chain polyethylene in the Ti-abundant catalyst particle shell and high molecular weight short-chain branched polyethylene in the Ti-scarce catalyst particle core. Co-monomers for the short-chain branched polymer were generated in situ within the TEAl-impregnated confined space of the Ti-scarce catalyst particle core in close proximity to the active sites that produced the high molecular weight polymer. These results demonstrate that the catalyst particle architecture directly affects polymer composition, offering the perspective of making high-performance polyethylene from a single reactor system using this modified Phillips catalyst. Two-in-one: A novel triethylaluminium-modified Phillips Cr/Ti/SiO2 ethylene polymerisation catalyst with two distinct active regions has been developed. STXM was used as a micro-spectroscopy method to discriminate between the active sites producing low molecular weight linear chain and high molecular weight short-chain branched polyethylene within a single catalyst particle. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution Non-Commercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Lansalot-Matras C.,CNRS Institute of Electronics and Telecommunications, Rennes | Lavastre O.,CNRS Institute of Electronics and Telecommunications, Rennes | Sirol S.,Total Research and Technology Feluy
Catalysis Communications | Year: 2015

In the field of transition metal catalysts for olefin polymerization, the discovery of new chelating ligands has attracted significant interest. This paper reports on the polymerization of ethylene with new chromium based catalysts containing an acetyl-hydroxy-fulvene ligand. A parallel method was applied to screen eleven metal salts versus two different functionalized fulvene ligands. A direct visual analysis showed solid PE formation only in vials containing a chromium salt after 1 h of polymerization at 35 °C and 15 bar. This preliminary screening was followed by optimization studies to obtain high activities (up to 5 tPE/(mol•h)). ORTEP structures of the corresponding ligands and of the best catalysts were reported. © 2014, Elsevier B.V. All rights reserved.

Rose A.,University of Bayreuth | Thiessen J.,University of Bayreuth | Jess A.,University of Bayreuth | Curulla-Ferre D.,Total Research and Technology Feluy
Chemical Engineering and Technology | Year: 2014

Langmuir-Hinselwood (LH) and power rate equations were applied to describe the kinetics of the Fischer-Tropsch reaction on cobalt catalysts and manganese-doped cobalt catalysts supported on carbon nanotubes (CNTs). LH-based kinetics characterize the activity behavior of the unpromoted Co/CNT system satisfactorily, but fail with respect to the manganese-promoted Co/CNT catalyst. An alternative LH equation is able to fit the experimental data, but the fitting parameters are out of the range of usual values and underrate the activity at ambient pressure regardless of manganese promotion. Application of power law rate expressions results in satisfying characterization of the kinetics in the whole CO pressure range in the promoted case and within a defined range of CO pressure in the unpromoted case. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cicmil D.,University Utrecht | Meeuwissen J.,Total Research and Technology Feluy | Vantomme A.,Total Research and Technology Feluy | Weckhuysen B.M.,University Utrecht
ChemCatChem | Year: 2016

A diffuse reflectance infrared Fourier-transform (DRIFT) study has been conducted at 373 K and 1 bar on an industrial Cr/Ti/SiO2 Phillips-type catalyst modified with, and without, triethylaluminium (TEAl) as co-catalyst. The reaction rate of the polymerization of ethylene, as monitored by the increase in the methylene stretching band of the growing polyethylene (PE), has been investigated as a function of the titanium content. After an initial period of mixed kinetics, with the reaction rate significantly higher for the TEAl-modified catalysts compared with the non-modified catalysts, the polymerization proceeded as a pseudo-zero-order reaction with a reaction rate that increased as a function of titanium loading. Furthermore, it was found that the higher Ti loading caused the appearance of more acidic hydroxyl groups and modified the Cr sites by making them more Lewis acidic, ultimately shortening the induction time and increasing the initial polymerization rate. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Maziers E.,Total Research and Technology Feluy
Society of Plastics Engineers - 2013 SPE International Polyolefins Conference | Year: 2013

This Paper will introduce the use of the rotomolding process together with a skin-foam-structure to produce plastic car bodies. These structures will be mainly dedicated to small city cars. The plastic bodies have a very good balance of weight /mechanical performances as well as a significant contribution in making the city car a sustainable part of mobility.

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