EFRI DCheM: Distributed solar energy harvesting for carbon-free ammonia synthesis

EFRI分布式化学制造项目旨在为在农场附近生产肥料提供科学和技术基础，并避免当前工业标准氨合成过程的大量温室气体足迹。小规模的分布式肥料生产对美国农村地区和世界上许多其他获得肥料有限的地区至关重要。分布式、小规模氨生产的太阳能驱动和无碳战略为农业社区提供了新的商业模式平台。靠近农场的分布式肥料生产为重大的全球影响提供了两条相互交织的途径：一条是减少肥料生产和运输过程中的碳排放，另一条是吸引农业和工业利益相关者，探索在美国农村社区以及遭受粮食不安全的低收入国家提供具有成本效益的肥料的最佳方法和适当规模。该项目的目的不是取代现有的工业氨合成基础设施。相反，其目标是通过在特定的农村地区（如美国印第安人部落经营的农场）实现可持续的分布式肥料生产过程，以满足物流和经济意义上的需求，从而满足未来对化肥需求的部分增长。该基础研究项目开创了光增强热催化的概念，不是在常温和常压下的液相间歇反应器中进行光催化反应，而是在中等温度和相对较低压力下的连续流动气固反应器中进行。因此，这项工作将为基本理解导致光增强氨形成速率的潜在物理和表面化学奠定基础。除了开发针对光相互作用优化的新型催化材料和催化剂结构外，该项目还通过在新型光催化反应器的催化剂板内均匀分布光，为反应器设计带来了重大创新。可再生能源驱动的水电解提供了所需的过程氢和氮从空气中分离出来，并进一步转化为肥料，如水氨、氨基甲酸酯或尿素。太阳光谱增强热催化的研究成果，结合该项目的社区和课程参与方法，将在三个方面推进学术研究：(1)对催化表面光增强氮活化的物理学的基本理解；(2)基于可再生氢的分布式氨合成与肥料生产集成系统的设计与建模；(3)对培训模块进行原型设计、试点和评估，以向利益相关者传达创新并走向实施。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This EFRI Distributed Chemical Manufacturing project seeks to provide the scientific and technical foundations for producing fertilizer close to the farm and for the avoidance of the significant greenhouse gas footprint of the current industrial standard ammonia synthesis process. Small-scale distributed fertilizer manufacturing is vital for rural areas of the U.S. and for many other regions of the world where access to fertilizer is limited. The solar energy-driven and carbon-free strategy of distributed, small-scale ammonia production provide a platform for new business models for agricultural communities. Distributed fertilizer manufacturing close to the farm offers two intertwined pathways for significant global impact: one toward decreasing the carbon emissions during production and transportation of fertilizer, and another toward engaging agricultural and industrial stakeholders and exploring the best methods and appropriate scales for providing cost-effective access to fertilizer in rural communities here in the U.S. as well as in low-income countries suffering from food insecurity. The project’s aims are not to replace the existing industrial ammonia synthesis infrastructure. Instead, the goal is to cover part of the future increased demand for fertilizer by enabling a sustainable distributed fertilizer manufacturing process for select rural locations such as farms operated by NativeAmerican Indian tribes on a scale where it makes logistical and economic sense.Th fundamental research project pioneers the concept of photo-enhanced thermal catalysis, conducting photocatalytic reactions not in a liquid phase batch reactor at ambient temperature and pressure, as is the general practice, but in a continuous flow gas-solid reactor at moderate temperatures and relatively low pressures. As such, this work will lay the foundation for a fundamental understanding of the underlying physics and surface chemistry that leads to photo-enhanced ammonia formation rates. Besides developing novel catalytic materials and catalyst architectures optimized for light interaction, the project also brings significant innovation to reactor design by distributing light uniformly within catalyst plates in a new type of photocatalytic reactor. Renewable energy-powered electrolysis of water provides the required process hydrogen and nitrogen is separated from the air and further converted into fertilizer, such as aqueous ammonia, carbamate, or urea. The solar-spectrum-enhanced thermal catalysis research results, combined with the project’s community and curricular engagement approach, will advance scholarship on three fronts: (1) fundamental understanding of the physics of photo-enhanced nitrogen activation on catalytic surfaces; (2) design and modeling of an integrated system for renewable-hydrogen-based distributed ammonia synthesis and fertilizer production; and (3) prototyping, piloting and assessment of training modules to convey the innovations to stakeholders and move towards implementation.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.