Removing the Quantum Barrier to Sustainable LH2 Fuel in Aviation: A Mechanistic, Process, and Environmental Life Cycle Assessment of the Ortho-Para Conversion in Liquefaction

作者：Paula Valentina Mendoza Moreno · 发表于：Apollo (University of Cambridge) · 年份：2026 · DOI：10.17863/cam.125200 · 研究领域：Hybrid Renewable Energy Systems、Catalysts for Methane Reforming、Chemical Looping and Thermochemical Processes

Liquid hydrogen (LH2) is a critical energy carrier for decarbonisation, yet its production is challenged by the high energy cost and boil-off losses associated with the exothermic ortho-to-para hydrogen conversion (OPC). A fundamental trade-off exists between the energy invested during liquefaction to achieve a high para-H2 content for storage stability and the practicality of producing lower-quality fuel for more immediate use. This Dissertation presents a comprehensive, multi-scale analysis of the OPC-integrated, H2 liquefaction process, linking fundamental reaction kinetics, process-level energy consumption, and life cycle environmental impact to establish a holistic framework for sustainable LH2 production. To quantify the techno-economic trade-offs, a large-scale hydrogen liquefaction process was modelled using Aspen Plus. This study systematically compared perfect, imperfect, and post-liquefaction OPC strategies. Results demonstrate that achieving high-purity (99.6%) para-H2 for long-term storage can increase the Specific Energy Consumption (SEC) by up to 57% compared to producing normal LH2, establishing a direct, quantifiable link between production energy and fuel storage quality. To understand the fundamental reaction mechanism, the cryogenic OPC kinetics were investigated experimentally over an IONEX® catalyst (27–77 K) using a differential reactor. A dual kinetic regime was identified, revealing a non-classical negative apparent activation energy below 35 K. This ...