Abstract: Ortho-para hydrogen conversion catalyst (OPC) is one of the key materials in large-scale hydrogen liquefaction projects. In recent years, research has primarily focused on enhancing the low-temperature catalytic activity of existing systems, while the accurate measurement of para-hydrogen content has become the foundation of such studies. However, only a limited number of studies and relevant industry standards have reported on the testing accuracy and reliability of para-hydrogen analysis, and reports on the batch preparation process remain scarce. Optimizing these processes to guide mass production is particularly crucial for reducing reliance on imported catalysts. This study explores both the catalytic testing analysis and the optimization of mass production processes for OPC. It not only demonstrates the stability and high measurement accuracy of the experimental results obtained from the self-developed testing platform, but also identifies the optimal mass production process combination to maximize yield through a comprehensive comparison of catalytic performance and mechanical strength. Furthermore, process optimizations such as low-temperature activation, particle size optimization, and secondary washing are implemented to produce catalysts with superior catalytic activity. The results show that the self-developed catalyst 2# with primary crushing, sieving through a 0.8 mm sieve, washing and low-temperature activation exhibits approximately 3.4% higher catalytic performance than imported catalysts at a space velocity of 1.2 L/(min·mL), with corresponding conversion rate and reaction rate constant (k value) approximately 7.42% and 25.78% higher, respectively. This study demonstrates that the self-developed catalysts with excellent performance can be achieved through batch preparation, providing critical support for domestic substitution.

Key words: ortho-para hydrogen conversion, catalyst, testing analysis, low-temperature catalytic activity, batch