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International audienceA proton exchange membrane (PEM) fuel cell, an alternative to combustion processes that consume fossil resources, is used to convert energy stored in the form of hydrogen into electricity. The membrane-electrode assembly (MEA), the core of this system, contains platinum, a noble metal, which is a limited resource. This paper presents an environmental assessment of a recycling process for the platinum catalyst contained in the MEA of a PEM fuel cell. During this study, four hydrometallurgical platinum recovery processes from Pt/C particles have been developed at the laboratory scale. The considered process alternatives are composed of the four following steps: leaching, separation, precipitation and filtration. Approximately 76% of the platinum can be recovered as [NH4]2PtCl6 salt using the most efficient process alternatives. In this case, platinum leaching is carried out with a mixture of H2O2 and HCl, followed by liquid/liquid platinum extraction and a precipitation step.The environmental assessment was performed using the SimaPro 8 tool coupled with the EcoInvent 3.1 database. The environmental impacts were estimated for a 25 cm2 active area MEA considering the production and end-of-life stages of the MEA life-cycle using the CML-IA baseline V3.02 method. The results show that more than half of the main impacts of the MEA life-cycle can be avoided for four relevant impact categories if platinum is recovered in the end-of-life of the product

Selective Pt and Co separation has been achieved, recycled Pt/C particles were synthesized, and excellent electrochemical properties have been observed.

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. Building new entities from existing titanium part by electron beam melting: microstructures and mechanical properties.

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To cite this version:Moinet Mireille, Guillaume Mandil, Philippe Serré. Defining tools to address over-constrained geometric problems. Computer-Aided Design, Elsevier, 2014, 48, pp. AbstractThis paper proposes a new tool for decision support to address geometric over-constrained problems in Computer Aided Design (CAD). It concerns the declarative modelling of geometrical problems. The core of the coordinate free solver used to solve the Geometric Constraint Satisfaction Problem (GCSP) was developed previously by the authors. This research proposes a methodology based on Michelucci's witness method to determine whether the structure of the problem is over-constrained. In this case, the authors propose a tool for assisting the designer in solving the over-constrained problem by ensuring the consistency of the specifications. An application of the methodology and tool is presented in an academic example.

International audienceEnd-of-Life (EoL) strategies, and especially products' lifespan extension, are becoming key issues for more and more manufacturers. Their implementations have to be done from the design stage and may be facilitated with design methodologies and guidelines. However, if a function of the system is no longer efficient enough during its use phase, in such a way that remanufacturing and upgrading may not be considered, the system has reached its final EoL, even if it might have been used for other applications. To address such kind of situations, the present paper investigates the concept of Design-2-Life (D2L) systems. To do so, EoL strategies will be explored to understand the key issues. Then a clear explanation of D2L concept will be proposed as well as its main characteristics. Finally we will discuss the challenges of this new approach and the advantages to develop it under a PSS framework. The case of batteries used in electric cars will be used to illustrate the concept