Posted BY
DLRYour mission: The specific Ph.D. will be based on commonalities in materials and reactors requirements among several solar energy conversion-, storage- and transformation- related, cyclic processes relevant to the use of Concentrated Solar Power (CSP) systems. In particular, with respect to the materials chemistry aspect, the so-called “oxygen-transfer” characteristics of oxide materials of multivalent metals via redox (reduction-oxidation) chemical reactions will be exploited. With respect to the reactor engineering aspect, the exploitation of porous ceramic structures such as honeycombs, foams or membranes, incorporating a high amount of these materials is targeted. In this perspective the Ph.D. dissertation work will comprise an integrated basic and applied research and technology approach covering all required steps: from powder synthesis and characterization of redox oxide materials, to their processing, functionalization, shaping and densification to structured ceramic porous components like those mentioned above, and their application-specific evaluation in laboratory-scale reactors. Targeted materials are oxides of transition and alkaline earth metals, (e.g. Fe, Mn, Ni, Co, Ca, Sr) and their combinations, with emphasis on perovskites. The specific targeted applications linked to the exploitation of Concentrated Solar Power are: Water/CO2 Splitting (WS/CDS) Thermochemical Cycles for hydrogen/syngas production combined splitting/methane reforming, “looping” processes for hydrogen/syngas production ThermoChemical Storage (TCS) of solar energy, hybridized with sensible storage high-temperature Solid Oxide Electrolysis Cells (SOECs) for Water/CO2 Splitting These four processes, splitting, looping, TCS and electrolysis, can be rendered solar-driven with high-temperature heat and/or power from CSP facilities. In such a function they involve not only cyclic gas-solid chemical reactions but heat exchange between a solar receiver, the heat transfer fluid employed therein and the units downstream. The major technical challenge lies in the proper design and operation of WS/CDS/Looping/TCS/SOECs reactors that will operate simultaneously and efficiently as heat exchangers. Thus the so-called “structured” reactor systems based on porous ceramic objects like honeycombs, foams or membranes are in principle suited for such applications. In this perspective the main objectives and tasks of your Ph.D. dissertation are: screening and optimization of perovskite compositions via thermodynamic calculations with respect to specific properties of merit like oxygen release/uptake, reaction enthalpies etc. synthesis of multicomponent perovskite powders by solid-state and liquid-phase techniques pre- and post-synthesis characterization of raw and synthesized powders with respect to critical properties (e.g. particle size, phase composition, specific surface area, micro-morphology) assessment of perovskite powders with respect to WS/CDS, splitting/reforming and TCS in suitable lab-scale reactor and TGA/DSC test rigs coupled with necessary monitoring, control and gas effluent analytic systems (e.g. mass-spectrometry, gas analyzers, oxygen sensors) development and validation of pertinent chemical kinetics models manufacture of lab-scale porous structures – honeycombs, foams, membranes - with high volumetric perovskite content from selected perovskite compositions, via the appropriate for each case dry, wet or plastic processing techniques (e.g. pressing, slurry coating, etc.) complemented by sintering and properties characterization (porosity, mechanical strength, etc.) assessment of perovskite-based porous structures with respect to long-term, cyclic splitting, looping and TCS operation in dedicated reactor test rigs and influence of key process parameters modeling and simulation of thermochemical stresses during cyclic oxygen transfer operation in porous ceramic objects to quantify the chemical/thermal contributions on dimensional changes and the critical chemical and thermal stresses as a function of perovskite compositions The Ph.D. dissertation will be carried out within multi-partner, EU co-funded research projects, in the framework of materializing the contractual research obligations of DLR therein. The Ph.D. degree will be awarded by the Technical University of Dresden (Technische Universität Dresden/TUD) Germany, within the joint professorship established by DLR and TUD in the Faculty of Mechanical Science and Engineering. Your qualifications: university degree in chemical engineering, materials engineering, process engineering or similar experience on inorganic (ceramic) powder synthesis and characterization techniques (indicative: XRD, SEM, DTA/TGA, N2 and Hg Porosimetry, etc.) knowledge of fundamental chemical reactor and heat exchanger design principles (chemical kinetics, heat and mass transport) experience with graphing and data analysis software (e.g. OriginLab or relevant) is appreciated ideally experience/familiarity with gas effluent analysis methods and equipment (e.g. mass spectrometry, chromatography or relevant) familiarity with data acquisition, signal processing and graphic environments (e.g. Labview) is desirable contact with hydrogen- and/or solar energy related technologies independent and structured way of working good oral and written communication skills fluent English and German language skills Your benefits: Look forward to a fulfilling job with an employer who appreciates your commitment and supports your personal and professional development. Our unique infrastructure offers you a working environment in which you have unparalled scope to develop your creative ideas and accomplish your professional objectives. We are striving to increase the proportion of female employees and therefore particularly welcome applications from women. Disabled applicants with equivalent qualifications will be given preferential treatment.
Hi! How can we help you?
Click below button to start chat