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Diffusiophoresis takes place when a particle in solution moves due to the presence of a solute concentration gradient. This phenomenon is often studied under some simplifying assumptions, such as negligible diffusive layer thickness or infinite diffusion coefficient. In this work we simulate diffusiophoresis without these simplifications. The goal of this numerical study is to investigate equilibrium and fully developed states of non-electrolyte phoretic systems. Simulation results show that equilibrium states depend on solute diffusivity and on a reference solute concentration far from the particle. An expression is regressed that gives the (equilibrium) diffusiophoretic velocity as a function of solute concentration gradient, solute diffusion coefficient and the reference solute concentration far from the particle. A different set of results reveals that the state of phoretic systems does not depend on the initial conditions when time goes to infinity. This motivates the definition of fully developed states, designating those systems whose properties no longer depend on initial conditions. Apart from these findings, this work also depicts the effect of solute–interface interactions on diffusiophoresis. Simulation results for two solid particles with different interaction potentials are used to illustrate particle separation via diffusiophoresis. Finally, values of particle mobility are calculated for different solute–interface attraction strengths. These results are compared with another work in the literature, which studies polymer diffusiophoresis via molecular simulations (Ramírez-Hinestrosa et al., J. Chem. Phys., vol. 152, 2020, p. 164901).

The field encompassing biomimetics, bioinspiration and nature inspiration in engineering science is growing steadily, pushed by exogenous factors like the search for potentially sustainable engineering solutions that might already exist in nature. With the help of information provided by a bibliometric database and further processed with a dynamic network and semantic analysis tool, we provide insight at two scales into the corpus of nature-inspired engineering field and its dynamics. At the macroscale, the Web of Science® (WoS) categories, countries and institutions are ranked and ordered by thematic clusters and country networks, highlighting the leading countries and institutions and how they focus on specific topics. Such an insight provides an overview at the macroscale that can be valuable to orient scientific strategy at the country level. At the mesoscale, where science is incarnated by collaborative networks of authors and institutions that run across countries, we identify six semantic clusters and subclusters within them, and their dynamics. We also pinpoint leading academic collaborative networks and their activity in relation to the six semantic clusters. Trends and prospective are also discussed. Typically, one observes that the field is becoming mature since, starting by imitating nature, it proceeded with mimicking more complex natural structures and functions and now it investigates ways used in nature in response to changes in the environment and implements them in innovative and adaptive artefacts. The sophistication of devices, methods and tools has been increasing over the years as well as their functionalities and adaptability, whereas the size of devices has decreased at the same time.

International audience; Gas-expanded liquids have been studied during past years; however, the physicochemical properties of some of these fluids still need to be characterized and understood. In particular, the study of properties concerning solvation and mass transport is key for industrial applications. This work presents the characterization of eight CO2-expanded biosourced solvents: organic carbonates (dimethyl, diethyl, ethylene, and propylene carbonates), anisole, veratrole, γ-valerolactone, and 2-methyltetrahydrofuran. Two approaches have been used: spectroscopic measurements and molecular modeling. Phase equilibrium was determined for each CO2/biosourced solvent system, and then the solvatochromic probe Nile Red was used to determine changes in dipolarity/polarizability (π* Kamlet–Taft parameter) by CO2 pressure. Molecular dynamics calculations were performed to determine the density and viscosity changes with CO2 pressure. It is shown in this study that the degree of modulation of dipolarity/polarizability parameter can go from that of pure solvent (around 0.4 for linear organic carbonates) to negative values, close to that of pure CO2 at the T and P used in this study. Concerning transport properties, such as density and viscosity, a great decrease in both these properties’ values was observed after swelling of the solvent by CO2, for instance, in linear organic carbonates where density can decrease to 50% the density of pure solvent; concerning viscosity a decrease of up to 90% was measured for these compounds. It was observed that the solubility of CO2 and then modulation of properties were higher in linear organic carbonates than in the cyclic ones. This study shows once more that CO2 has a great capacity to be used as a knob for triggering changes in the physicochemical properties of green biosourced solvents that can help to implement these solvents in industrial applications.

International audience; The separation of ternary nonideal systems with multi‐azeotrope is very important because they are often found in the waste of chemical and pharmaceutical industries, which is much more difficult due to the formation of multi‐azeotrope and distillation boundary. We propose a systematic procedure for design and control of a triple‐column pressure‐swing distillation for separating ternary systems with three binary minimum azeotropes. This procedure involves thermodynamic insights, a two‐step optimization method, and effective control strategy. The separation of tetrahydrofuran (THF)/ethanol/water is used to illustrate the capability of the proposed procedure. It is found that the pressure limits in columns can be determined through the analysis of residue curve maps, distillation boundary, and isovolatility curves. The optimal triple‐column pressure‐swing distillation is generated with the minimum total annual cost (TAC) of $2.181 × 106 in sequence A. The operating conditions are well controlled approaching their desired specifications in an acceptable time when disturbances occur.

International audience; Cette communication relate une expérience de formation conçue et réalisée par une équipe interdisciplinaire au sein d’une organisation internationale, en vue de co-concevoir des situations de travail protectrices pour la santé. Considérée comme une forme d’intervention fondée sur un apprentissage expérientiel, la formation combine des séquences individuelles et collectives conçues de manière à développer : la capacité réflexive des personnes à examiner leur situation de travail dans une perspective systémique ; et la coopération de manière à intégrer la diversité des points de vue dans l’élaboration de solutions qui garantissent l’efficience et la santé à tous les niveaux de l’organisation. Les résultats présentent les apports et défis de cette formation au niveau de l’équipe de formateurs, des participants et de l’écosystème de travail. Ils sont ensuite discutés au regard de l’analyse du travail qui a servi d’objet partagé au sein de l’équipe pour concevoir l’action de formation, et entre l’équipe et les participants pour co-concevoir leurs propres situations de travail.

International audience; In order to guarantee safe handling of a combustible liquid, such as biodiesel, it is important to be aware of its Flash Point (FP). Thus, the present study focused on FP experimental measurement and thermodynamic correlation of binary and ternary mixtures of saturated or unsaturated fatty acid ethyl esters (FAEEs) as surrogates for biodiesel. FP of different types of ethylic biodiesel in terms of feedstock (canola, corn, cotton and soy oils) were also measured and compared with the predicted values. Experiments were carried out in agreement with the standard closed cup procedure ASTM D6450. Liaw’s model was applied to FP prediction, with liquid phase non-ideality description accounted for by UNIFAC group contribution models (Original UNIFAC, UNIFAC-Dortmund and UNIFAC-Bessa with revised parameters for fats). FP prediction accounting for non-ideality proved to be accurate, with some difference between the UNIFAC type models and Root Mean Square Deviations (RMSD) varying from 0.27 K to 3.95 K for binary and ternary mixtures.

Edible oil extraction is a large and well-developed sector based on solvent assisted extraction using volatile organic compounds such as hexane. The extraction of oil from oilseeds generates large volumes of oilseed by-products rich in proteins, fibres, minerals and secondary metabolites that can be valued. This work reviews the current status and the bio-macro-composition of oilseeds, namely soybean, rapeseed, sunflower and flaxseed, and the refining process, comprising the extraction of oil, the valorisation and separation of valuable secondary metabolites such as phenolic compounds, and the removal of anti-nutritional factors such as glucosinolates, while retaining the protein in the oilseed meal. It also provides an overview of alternative solvents and some of the unconventional processes used as a replacement to the conventional extraction of edible oil, as well as the solvents used for the extraction of secondary metabolites and anti-nutritional factors. These biologically active compounds, including oils, are primordial raw materials for several industries such as food, pharmaceutical or cosmetics.

International audience; Mutations in the energy sector are shifting the production and distribution systems from a centralized to a decentralized model. Within this context, we address the economics of grid-connected Hybrid Renewable Energy Systems (HRES) in relation with energy management strategies by considering taxes and economic regulation frameworks. Therefore, we propose a model to perform economic analysis of such HRES formulated as a MILP (Mixed Integer Linear Programming) model in the context of the French regulation. We test it on the case study of an integrated PV installation for French households’ self-consumption, comparing two household sizes: a two persons household with a consumption of 4000 kWh/year and a five persons household consuming 8500 kWh/year; and two solar exposures: one of 1400 h of equivalent maximum production and one of 1060 h. The main results is that the current regulation framework for incentive calculus does not encourage citizens to install a maximum of PV panels as well as it does not guarantee a uniform development of self-consumption infrastructure. Alternatively, we propose a new regulation framework in order to reverse those tendencies.

Nature is fascinating. It is even more awesome when scru-tinised from a scientific, mechanistic angle across lengthscales, down to the nanoscale, unravelling complex structuresand patterns. Natural systems consist of a dynamic, complexassembly of interacting components and systems, leadingto emergent behaviour, achieving tasks ultimately aiming atsurvival, which, very roughly, translates into sustaining cur-rent activities. Such activities include processing matter andenergy, transporting fluids, changing phase state to obtainproducts of high quality, and communication. The similar-ity is striking with what processes in chemical engineeringare intended for, since they also deal with the processing ofmatter, energy and data...

International audience; The viscosity of edible oils was measured before and after hydrogenation to assess a new model for predicting the viscosity of partially hydrogenated oils with given saturation degree and temperature. This contribution group model is based on a semi-predictive approach, and can be used to estimate viscosity changes due to hydrogenation. It was experimentally validated using three different oils, and the results show an overall relative average deviation of 3.7%. The model was implemented in a transient CFD simulation of a three-phase monolith catalytic reactor for edible oil hydrogenation. Hydrogenation in Taylor flow was described with the unit cell approach. The influence of viscosity changes on the reaction yield and selectivity were investigated in relation with the coupling between hydrodynamics, mass transfer, and reaction kinetics. This effect proved to be significant in the former case; the reactor length was increased by a factor 1.5, yielding approximately 30% conversion.

International audience; Residue curve maps (RCMs) and univolatility curves are crucial tools for analysis and design of distillation processes. Even in the case of ternary mixtures, the topology of these maps is highly non-trivial, as shown by Serafimov’s and Zhvanetskii’s classifications. We propose a novel method allowing detection and computation of the existence of univolatility curves in homogeneous ternary mixtures independently of the presence of azeotropes, which is particularly important in the case of zeotropic mixtures. The method is based on analysis of the geometry of the boiling temperature surface constrained by the univolatility or unidistribution condition. The introduced on the concepts of the generalized univolatility and unidistribution curves in the three dimensional composition – temperature state space that lead to a simple non iterative and efficient algorithm of computation of the univolatility curves. Two peculiar ternary systems, namely diethylamine – chloroform – methanol and hexane – benzene – hexafluorobenzene are used for illustration. When varying pressure, tangential azeotropy, bi-ternary azeotropy, saddle-node ternary azeotrope, and bi-binary azeotropy are found. In both examples, a distinctive crossing shape of the univolatility curve appears as a consequence of the existence of a common tangent point between the three dimensional univolatility hypersurface and the boiling temperature surface. Moreover, rare univolatility curves starting and ending on the same binary side are found.

Designing a sustainable and economical distillation system is a big global challenge in the industrial chemical field. To address this issue, one of most promising solutions is the so-called dividing wall columns addressed in this work, which not only can cut energy cost but also use limited installation space. An improved shortcut design approach is developed in this work to provide accurate models for each section of dividing wall columns; meanwhile Underwood’s and Gilliland’s equations are employed to determine minimum reflux ratio and total number of stages in different column sections in terms of corresponding design specifications and operating conditions. This proposed approach has been applied to separations of mixtures of hydrocarbons and alcohol with different values on the ease of separation index. To test its effectiveness, the preliminary design parameters obtained through the improved proposed shortcut method are further validated by a rigorous simulation in Aspen HYSYS. Furthermore, the res...

Instability in bottled wines refer to tartaric salts crystallization such as potassium bitartrate (KHT). It is not desirable as consumers see the settled salts as an evidence of a poor quality control. In some cases, it causes excessive gushing in sparkling wine. We investigate the effect of two oenological carboxymethylcellulose (CMC) for KHT inhibition in a model solution of white wine by studying the impact of some properties of CMC such as the degree of polymerization, the degree of substitution, and the apparent dissociation constant determined by potentiometric titration. Polyelectrolyte adsorption is used for determining the surface and total charge and for providing information about the availability of CMC charged groups for interacting with KHT crystal faces. The inhibitory efficiency of CMC on model solution is evaluated by measuring the induction time with the help of conductimetric methods. Crystals growth with and without CMC are studied by observation with MEB and by thermal analysis using DSC. The results confirm the effectiveness of CMC as an inhibitor of KHT crystallization in a model solution. The main hypothesis of the mechanism lies in the interaction of dissociated anionic carboxymethyl groups along the cellulose backbone with positively charged layers on KHT faces like the {0 1 0} face. Key factors such as pH, CMC chain length and total charge are discusses.

Project developer in the domain of land settlement project are involved with many stakeholders and are usually overflown by data relative to technical, economic and social issues. This paper contributes to the necessary multi-scale approach challenge and we propose a holistic framework that enables to describe the development process of land settlement project and assess its sustainability. It would help developers to take decisions compliant with the project complexity. In the model driven engineering perspective, the metamodel framework is described with the ISO 19440 four views to represent complex systems: architectural, structural, functional and behavioural. We confront it to describe two case studies: the successful project of hydro-wind power plant in El Hierro in the Canaries, and the Sivens Dam project in France sadly famous for its deadly outcome. Their comparison enables us to draw hypothesis on what are the ingredients of success and validate the framework.

International audience; We investigate the use of computer aided molecular design (CAMD) approach for enhancing the properties of existing molecules by modifying their chemical structure to match target property values. The activity of tailoring molecules requires to aggregate knowledge disseminated across the whole chemical enterprise hierarchy, from the manager level to the chemists and chemical engineers, with different backgrounds and perception of what the ideal molecule would be. So, we propose a framework that allows the search to be successful in matching all requirements while capitalizing this knowledge spread among actors with different backgrounds with the help of SBVR (Semantics of Business Vocabulary and Rules) and OCL (Object Constraint Language). In the context of using biomass as the feedstock, we discuss the coupling of CAMD tools with computer aided organic synthesis tools so as to propose enhanced bio-sourced molecule candidates which could be synthesized with eco-friendly pathways. Finally, we evaluate the sustainability of the molecules and of the whole decision-process as well. Specific applications that concern the use of bio-sourced molecules are presented: a case of typical derivatives of chemical platform molecules issued from the itaconic acid to substitute N-methyl-2-pyrrolidone NMP or dimethyl-formamide DMF solvents and a case of derivatives of lipids to be used a biolubricants.

International audience; Nature-inspired chemical engineering (NICE) is promising many benefits in terms of energy consumption, resilience and efficiencyetc.but it struggles to emerge as a leading discipline, chiefly because of the misconception that mimicking Nature is sufficient. It is not, since goals and constrained context are different. Hence, revealing context and understanding the mechanisms of nature-inspiration should be encouraged. In this contribution we revisit the classification of three published mechanisms underlying nature-inspired engineering, namely hierarchical transport network, force balancing and dynamic self-organization, by setting them in a broader framework supported by nonequilibrium thermodynamics, the constructal law and nonlinear control concepts. While the three mechanisms mapping is not complete, the NET and CL joint framework opens also new perspectives. This novel perspective goes over classical chemical engineering where equilibrium based assumptions or linear transport phenomena and control are the ruling mechanisms in process unit design and operation. At small-scale level, NICE processes should sometimes consider advanced thermodynamic concepts to account for fluctuations and boundary effects on local properties. At the process unit level, one should exploit out-of-equilibrium situations with thermodynamic coupling under various dynamical states, be it a stationary state or a self-organized state. Then, nonlinear phenomena, possibly provoked by operating larger driving force to achieve greater dissipative flows, might occur, controllable by using nonlinear control theory. At the plant level, the virtual factory approach relying on servitization and modular equipment proposes a framework for knowledge and information management that could lead to resilient and agile chemical plants, especially biorefineries.

International audience; Modelling and experimental validation of solvent recovery from an aroma mixture by batch distillation process is presented, with particular emphasis of the effect of the prediction of the physicochemical properties and the phase equilibrium data on the content of the aroma compounds in the distillate cuts. The illustrative case study refers to an industrial batch distillation to recover dimethyl carbonate (DMC) from an extract generated by a solvent extraction process involving variable natural raw materials for tailored perfume and fragrance applications. Due to the high number of aroma compounds in natural extracts, a synthetic mixture containing six target aroma compounds (alpha-pinene, eucalyptol, linalool, cis-3-hexenol, fenchone and benzyl acetate) was mixed with DMC for the modelling and experimental studies of the batch distillation process. The methodology is tested through the simulation of the process with BatchColumn (R) software. As physicochemical properties of the aroma compounds and the vapour liquid equilibrium (VLE) of all involved mixtures are required for simulation study, group contribution methods are used to predict missing properties such as vapour pressure, vaporisation enthalpy and liquid and vapour heat capacities. For VLE calculation, the modified UNIFAC group contribution method is considered and new binary interaction parameters for the main groups COO and CH2O are regressed from experimental data. Simulation results are in good agreement with experiments carried out in a fully automated batch distillation column at 15 kPa and help optimise the industrial process operation. The proposed methodology can be applied for the design of other solvent recovery process in fragrance industry.

International audience; We show that the solvent behaviour in both diffusio-osmosis and Marangoni flow can be derived from a simple model of colloid-interface interactions. We demonstrate that the direction of the flow is regulated by a single value of the attractive parameter covering the purely repulsive and attractive – repulsive interaction cases. The proposed universality between diffusio-osmosis and Marangoni flow is extended further to include diffusio-phoresis. In particular, an object immersed to a colloidal solution moves towards the low concentration of the colloidal particles in the case of colloid-interface repulsion and towards the high concentration of the colloidal particles in the case of colloid-interface attraction. The approach combines the methods of fluid dynamics, molecular physics and transport phenomena and provides a tractable explanation of how the colloid-interface interactions affect the momentum balance and the transport phenomena (interfacially driven transport).

International audience; The energy sector is mutating with an increasing share of renewable energy. Renewable energy developers are facing new challenges, in particular sizing systems that combine multiple production sources and storage devices to match demand. Accordingly, this paper proposes a flexible metamodel architecture and a C++ software implementation for the grassroots design of Hybrid Renewable Energy System (HRES). The metamodel enables one to build optimization problem formulated as a Mixed Integer Linear Problem (MILP) with a tailor-made objective function to find the optimal size of HRES. The flexibility of the metamodel lies in its ability to handle many hybrid system configurations for three common types of usages of HRES, either for onsite demand, remote demand or a combination. It is demonstrated with two specific case studies, a stand-alone HRES composed of PV panels, battery set, and a diesel generator; and a factory in a tropical island. This paper contributes to a better adoption of cleaner production systems since it provides to decision makers a tool for HRES assessment

International audience; Extractive distillation processes enable the separation of non-ideal mixtures, including minimum or maximum boiling azeotropes and low relative volatility mixtures. Unlike azeotropic distillation, the entrainer fed at another location than the main mixture induces an extractive section within the column. A general feasibility criterion shows that intermediate and light entrainers and heterogeneous entrainers are suitable along common heavy entrainers. Entrainer selection rules rely upon selectivity ratios and residue curve map (rcm) topology including univolatility curves. For each type of entrainer, we define extractive separation classes that summarize feasibility regions, achievable products and entrainer – feed flow rate ratio limits. Case studies are listed as supplementary materials. Depending on the separation class, a direct or an indirect split column configuration will allow to obtain a distillate product or a bottom product, which is usually a saddle point of rcm. Batch and continuous process operations differ mainly by the feasible ranges for the entrainer – feed flow rate ratio and reflux ratio. The batch process is feasible under total reflux and can orient the still path by changing the reflux policy. Optimisation of the extractive process must systematically consider the extractive column along with the entrainer regeneration column that requires energy and may limit the product purity in the extractive column through recycle. For the sake of reducing the energy cost and the total cost, pressure change can be beneficial as it affects volatility, or new process structures can be devised, namely heat integrated extractive distillation, extractive divided wall column or processes with preconcentrator.

This work provides a short review of extractive distillation (ED) technology, covering all relevant topics: concept and working principles, residue curve maps, solvent design, screening and selection, types of mass separating agents, influence on VLE, solvent-to-feed ratio, process design, advanced ED in dividing-wall columns, and a list of applications.

International audience; There is rich literature on the separation of binary azeotropic mixtures, whereas few studies exist on the separation of biazeotropic ternary mixtures. In this work, we propose a systematic approach for energy-efficient extractive distillation processes for the separation of a biazeotropic mixture that involves thermodynamic insights via residue curve maps and the univolatility line to find the optimal entrainer and operating pressure, global optimization based on a proposed two-step optimization procedure, and double-effect heat integration to achieve further saving of energy consumption. An energy-saving reduced-pressure extractive distillation (RPED) with a heat integration flowsheet is then proposed to achieve the minimum total annual cost (TAC). The results show that the TAC, energy consumption, and exergy loss of the proposed RPED with heat integration are reduced by 75.2%, 80.5%, and 85.8% compared with literature designs.