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Aims The aim of this study is to evaluate the usefulness of a personalized discharge checklist (PCL) based on simple baseline characteristics on mortality, readmission for heart failure (HF), and quality of care in patients hospitalized for acute HF. Methods and results We designed an algorithm to generate PCL, based on 2016 HF European Society of Cardiology Guidelines and the screening of common comorbidities in elderly HF patients. We prospectively included 139 patients hospitalized for HF from May 2018 to October 2018. A PCL was fulfilled for each patient at admission and 24 to 48 hours before the planned discharge. A control cohort of 182 consecutive patients was retrospectively included from May 2017 to October 2017. The primary composite endpoint was mortality or readmission for HF at 6 months. The secondary endpoints were mortality, readmission for HF, and quality of care (evidence‐based medications, management of HF comorbidities, and planned care plan). There was no difference among baseline characteristics between PCL and control cohorts; mean age was 78.1 ± 12.2 vs. 79.0 ± 12.5 years old (P = 0.46) and 61 patients (43.9%) vs. 63 (34.6%) had HF with left ventricular ejection fraction (LVEF)

International audience; Bridging the gap between kinetic model conception and catalyst design is targeted in catalytic naphtha reforming process development. New catalysts are continuously optimised in order to achieve higher selectivity in C5+ products. An adequate description of catalytic transformations by the kinetic models would therefore provide clues for catalyst design and accelerate the time to market implementation of process simulators. This study investigates the influence of site density and location on n-heptane reforming selectivity. It identifies the nature of the limiting steps for the different reforming pathways on a broad range of catalyst formulations. A common lumped model using power law kinetics is developed to describe already published experimental observations on the set of selected catalysts. Linear free energy relationships are used in order to handle a reduced number of statistically relevant adjustable parameters. The dependence between reference rate constants and active phase formulation is then unravelled. Unexpected results indicate that chlorine content and repartition at the crystallite scale affects the hydrogenolysis activity. Within the range of tested formulations, this study suggests that hydroisomerisation reactions are limited by acid sites transformations whereas the aromatisation pathways seem to proceed through a metal/acid bi-functional scheme. The further elaboration of a kinetic model that is able to predict the effect of an industrial catalyst active phase formulation change in full naphtha cut reforming lies beyond the scope of this article.

SSCI-VIDE+ING+OSA:VPT:DFA:FMO; International audience; The synthesis of 19 carefully selected Pt/γ‐Al2O3−Cl formulations was followed by high‐throughput catalytic testing in order to unravel the effect of an active phase formulation change on n ‐heptane reforming performances. Pt/γ‐Al2O3−Cl catalysts were prepared with different Pt (0.3–1 %wt) and Cl (0.1–1.4 %wt) contents and using two γ‐Al2O3 supports so that both sites concentrations and sites locations at the crystallite surface vary among the catalyst pool. Catalytic tests were conducted in mild conditions for a comparison of catalysts in kinetic regime. Results show that Pt and Cl concentrations control the competition between hydroisomerisation, hydrogenolysis and hydrocracking pathways. Aromatisation, on the contrary, is poorly affected by formulation changes. Non‐monotonous trends linking Pt/Cl ratio to isomerisation selectivity are found for both γ‐Al2O3 supports. This study provides new insights for the description of bi‐functional transformations in catalytic naphtha reforming.

SSCI-VIDE+ING+OSA:DFA; International audience; Several major refining catalytic processes show a strong dependence of overall performances upon catalyst formulations and their structure. This observation is particularly true in naphtha catalytic reforming for which the product distribution is sensitive to slight changes in active phase formulations. This review presents different issues encountered in naphtha reforming that are related to active phase formulation changes. Two research and development approaches are usually proposed. (i) Rationalise the development of new catalytic formulations in order to increase selectivity towads valuable products. (ii) Design simulators that would guide operation in order to maintain process performances. Current limitations to a faster process development come from the disjunction between kinetic modelling and catalyst optimisation. This critical review is not an extensive analysis of existing naphtha reforming kinetic modelling methodologies or advances in catalytic behaviour elucidation. Rather, it proposes an original and pragmatic process development approach aimed at merging catalyst development with kinetic modelling through the identification of “effective” and “measurable” catalytic descriptors. The specificities of the structure–property relationships of naphtha reforming catalysts are reviewed and taken into account in order to list potential catalytic descriptors for this process. A focus is made on a current bottleneck faced in the description of the active phase which lies in understanding the role of the proximity and the interaction between acid and metallic sites in the balance between different bi-functional pathways. A variety of experimental approaches that can be used to measure these naphtha reforming active phase catalytic descriptors are presented and compared.

International audience; A laboratory pilot unit has been developed to solve the issues of thermodynamic equilibrium shift for the transesterification of vegetable oil into biodiesel. It consists in a two stages continuous heterogeneous catalytic reactor operating at 50 bar and 175 degrees C. Under the working conditions, only one homogeneous phase can be assumed. The reactions of transesterification need a large excess of methanol implying an additional energy consumption and higher capital expenditure because of larger size of equipments, and operating pressure. In this work, a numerical model has been developed in order to better understand the different coupled phenomena (thermodynamic equilibrium, kinetics, mass transfer limitations, etc.) governing biodiesel production. The model is based on a heterogeneous plug flow reactor with axial dispersion taking into account mass transfer in the catalyst and dynamic aspects. The reactor is supposed isothermal since transesterification reactions are almost athermic. Kinetic parameters have been optimized by comparison with experimental results previously obtained by IFPEn. Simulation results are used to establish the future experimental conditions that will be used on the pilot unit. Mass transfer limitations are characterized by changing the diameter of catalyst particle. Concentration and reaction rate profiles are depicted in the fluid phase and in the catalyst. The simulations indicate that a conversion of triolein of 87% can be reached with a methanol to triolein molar ratio of 36 at reactor inlet and with a mean residence time of 1 h.

International audience; The transesterification of vegetable oils by methanol implies a set of three parallel–series reversible reactions. Over a heterogeneous catalyst, reactions are limited by molecular diffusion, resulting in the use of a large excess of methanol to achieve a high conversion. This excess is detrimental to process efficiency because it involves large energy requirement for downstream separation. In order to identify the coupled physico-chemical phenomena and to optimize the process, a pilot unit was developed to perform transesterification of triglycerides with methanol over a solid ZnAl2O4 catalyst in a tubular fixed bed reactor under high pressure and temperature. The effects of different parameters such as particle diameter, temperature, residence time and molar feed ratio of methanol to triglyceride on fatty acid methyl ester (FAME) yield and triglyceride (TG) conversion were studied. A pseudo-homogeneous reactor model has been developed to identify rate laws and kinetic parameters by exploiting the experimental data in stationary regime. A set of kinetic constants was also determined for the given catalyst considering two kinetic models: an Eley–Rideal model with the reaction between TG and methanol as the rate determining step and a classical second order model taking into account thermodynamic equilibrium without adsorption. A heterogeneous model has also been established to determine molecular diffusion coefficients for each species in the mixture, through the use of experimental results in the transient regime. These molecular diffusion coefficients are dependent on the mixture viscosity and temperature. As a result, it was determined that diffusion of triglycerides and the first reaction kinetic rates are limiting the global conversion of the system.

This paper focuses on the impact of reactant staging on conversion for one single reversible reaction in a two-stage, isothermal, continuous reactor. The analytical expression of global conversion has been derived for a series of two continuously stirred-tank reactors. Improvements in the overall conversion and yield by staging can be obtained for low Damköhler number systems leading to low conversions, when the volumetric flow rate of the staged reactant has a higher value than that of the other one. The example of triolein transesterification involving three reversible reactions in a two-stage plug flow reactor is also studied as a concrete example of a consecutive/parallel reversible reactions system. Results are obtained by using a pseudo-homogeneous model and are compared with those obtained with a heterogeneous model from a previous study.