Thermally Stable Complex Redox Materials for Hydrogen Generation in Thermochemical Water-Splitting Process

Pi：申德，Rajesh V.机构：南达科他州采矿与技术学院建议编号：1134570标题：热化学水分离过程中用于制氢的热稳定复杂氧化还原材料世界未来的能源需求必须至少部分由可持续能源来满足。太阳能可以被利用来生产氢气，例如一种新的高温热化学水裂解制氢技术，这是一种很有前途的绿色技术，包括使用氧化还原材料的低温水裂解步骤和高温再生步骤的循环操作。由于氧化还原过程的周期性，氧化还原材料会经历热疲劳，从而导致晶粒长大或烧结导致比表面积减小，从而无法实现稳定的产氢水平。为了使这项技术具有成本竞争力，太阳能聚光器或核电站产生的过热蒸汽需要经过数百次热化学循环才能生产氢气，这对科学家和反应工程专业人员构成了巨大的挑战。计划一项为期三年的计划，利用氧化还原材料的热稳定形态，研究在多个热化学循环中高温水裂解产生氢气的情况。这些材料将通过溶胶-凝胶法和自蔓延高温合成(SHS)方法结合微波处理而得到不同的形貌，例如，核-壳或具有YSZ(氧化钇稳定的氧化锆)的偏析晶界。在氧化还原材料中，由于尖晶石铁氧体、黄铁矿及其组合被认为是有效的热化学水分解，PI计划合成这些具有热稳定形貌的材料，包括MFe2O4、M1xM2yFe2O4和M1xM2yM3zFe1-x-y-ZO(其中M、M1、M2和M3可以是Ni、Zn、Sn、Mn和Li)，并研究填充床反应器中的氢气产生以及在多个热化学循环中的动力学和传输特性，以期达到稳定的氢气水平。这两位研究人员在铁氧体的合成和热化学水分解过程中产生氢气方面都有经验。调查人员中的全仪表化反应堆设置？实验室已经建成并进行了测试。SDSM&amp；T提供了所有必要的表征仪器。该项目的智能优势在于，在使用热稳定的新型氧化还原材料的多个热化学循环中，通过高温水裂解产生氢气。通过更好地了解内部合成的氧化还原材料在热疲劳下不同形貌的微观结构稳定性以及产氢的动力学和传输过程，将丰富这一知识。实验研究应该加强对氧化还原材料热稳定所涉及的物理和化学过程的了解？在数百次热化学循环中保持稳定的产氢水平，而不会使复杂的铁氧体变质。更广泛的影响：这两位研究人员通过支持SDSM&A；T和NSF-REU项目的学生，积极参与促进本科生的研究经验。SDSM&A；T将大力培养化学和生物工程硕士和博士研究生。研究结果将通过发表在同行评议期刊上的出版物以及在国内和国际会议上发表的报告来传播。参与该研究项目的学生将在可持续能源、高温氧化还原材料和氢气生产的反应工程方面有实践经验。调查人员计划在这一领域加强对美洲原住民、初中生和教师的外联活动。

PI: Shende, Rajesh V. Institution: South Dakota School of Mines and TechnologyProposal Number: 1134570Title: Thermally Stable Complex Redox Materials for Hydrogen Generation in Themochemical Water-Splitting ProcessWorld future energy demands must be fulfilled, at least in part, by sustainable energy resources. Energy from the sun can be harnessed for the production of hydrogen such as a new high temperature thermochemical water-splitting technology for hydrogen production, which is a promising green technology involving a cyclic operation of a low-temperature water-splitting step and a high temperature regeneration step using redox materials. Because of the cyclic nature of the process, the redox materials undergo thermal fatigue leading to decrease in surface area due to grain growth or sintering and consequently, steady hydrogen production levels are not realized. In order for this technology to be cost-competitive, hydrogen production from superheated steam generated in a solar concentrator or in a nuclear plant needs to be demonstrated in hundreds of thermochemical cycles, which poses a great challenge for the scientists and reaction engineering professionals. A three-year program is planned to investigate hydrogen generation by a high-temperature water-splitting in multiple thermochemical cycles using thermally stabilized morphologies of redox materials. These materials will be synthesized by the sol-gel and self-propagation high temperature synthesis (SHS) methods coupled with microwave processing leading to different morphologies, for instance, the core-shell or segregated grain boundaries with YSZ (yttria-stabilized zirconia). Among redox materials, as ferrites with spinel, wustite and their combinations are known to be effective for thermochemical water-splitting, the PIs plan to synthesize these materials with thermally stable morphologies, which include MFe2O4, M1xM2yFe2O4, and M1xM2yM3zFe1-x-y-zO (where M, M1, M2, and M3 can be Ni, Zn, Sn, Mn and Li) and investigate hydrogen production in a packed-bed reactor and kinetics and transport properties in multiple thermochemical cycles with a view to achieving steady hydrogen levels. Both investigators have experience with the synthesis of ferrites and hydrogen production from the thermochemical water-splitting process. The fully instrumented reactor set-up in the investigators? laboratory is already built and tested. All necessary characterization instruments are available at SDSM&T. The intellectual merit of this project is in the area of hydrogen generation by high temperature water-splitting in multiple thermochemical cycles using thermally stabilized novel redox materials. This knowledge will be enriched by better understanding of the microstructural stability of different morphologies of in-house synthesized redox materials under thermal fatigue and kinetics and transport processes for hydrogen generation. The experimental studies should enhance the knowledge of the physical and chemical processes involved in the thermal stabilization of redox materials? morphologies and reaction engineering aspects leading to stable hydrogen production levels in hundreds of thermochemical cycles without deterioration of complex ferrites. Broader impacts: Both investigators have been actively involved in promoting research experience for undergraduate students by supporting students from SDSM&T and NSF-REU program. A significant effort will be on education of graduate students in both MS and PhD programs in chemical and biological engineering at SDSM&T. Results generated from the research will be disseminated via publications in peer-reviewed journals and presentations at national and international conferences. Students involved in this research program will have hands-on experience in the areas of sustainable energy, high temperature redox materials and reaction engineering aspects of hydrogen production. The investigators plan to enhance outreach activity in this area to Native Americans, middle and high school students and teachers.