Catalytic reforming in the process of hydrogen hydrocarbons, such as n-heptane, using catalists and hight temperatures

Catalytic Reforming of Hydrocarbon Feedstocks for Hydrogen (H₂) Production: Thermophysical Optimization Using n-Heptane as a Model Compound. The global transition toward sustainable energy systems places hydrogen (H₂) at the forefront of scientific and technological innovation. As a clean fuel with high energy density and zero carbon emissions at the point of use, hydrogen (H2) is a key enabler in decarbonizing power generation, transportation, and industrial processes. However, the realization of a hydrogen (H2)-based economy requires scalable, efficient, and regionally adaptable production methods that minimize environmental impact and integrate seamlessly into existing infrastructure. This study presents a comprehensive theoretical and experimental analysis of hydrogen (H2) production via catalytic reforming of hydrocarbon feedstocks, with a focus on n-heptane as a model compound. The research addresses critical challenges in H2 generation, including reaction kinetics, heat and mass transfer, catalyst stability, and measurement accuracy under high-temperature and supercritical conditions that promote effective H2 release. The selection of n-heptane is based on its well-characterized thermophysical properties and its representativeness of heavier petroleum fractions, ensuring experimental reproducibility and applicability to real-world feedstocks for H2 production. Catalytic reforming of n-heptane initiates dehydrogenation reactions, leading to hydrogen (H2) release according to the scheme:  C₇H₁₆ ^ C₇H₁₄ + H2

The objective of this research is to validate the feasibility of producing hydrogen (H2) through thermocatalytic 4^4 reforming of n-heptane using a custom-designed experimental setup that simulates industrial conditions. The system enables precise control of temperature, pressure, flow rate, and catalyst composition, allowing systematic exploration of reaction regimes and their impact on H2 yield and selectivity. Special attention is given to supercritical conditions, which enhance convective heat transfer, accelerate reaction kinetics, and improve energy efficiency, positioning catalytic reforming as a promising alternative to conventional hydrogen (H2) production methods such as steam methane reforming (CH4 + H2O ^ CO + ЗН2), water electrolysis (2ЩО ^ 2H2 + O2), and biomass gasification. Experiments were conducted in vertical, horizontal, and inclined pipe configurations to investigate the influence of geometry on thermal gradients, fluid dynamics, and catalyst performance in H2 evolution. The integration of high- precision thermocouples, pressure sensors, flow meters, and electronic potentiometers enabled real-time data acquisition and rigorous error analysis, including deviations in temperature, pressure, and flow rate that affect the accuracy of H2 yield calculations. Catalytic reforming involves complex reactions - dehydrogenation, cracking, isomerization, and aromatization - all contributing to hydrogen (H2) release. For example: C7H16 + Heat + Catalyst ^ C₆H₆ + CH4 + H2

By analyzing n-heptane behavior under controlled thermal conditions, the study identifies optimal parameters that maximize H2 output while minimizing byproducts such as CO, CH4, and coke. The use of thermally stable and active catalysts ensures sustained performance over extended operational cycles, which is essential for industrial-scale H2 production. The adaptability of n-heptane as a feedstock is particularly relevant for regions with limited access to natural gas or renewable electricity, offering a transitional solution that leverages existing petrochemical resources for H2 generation. The experimental setup and methodology are designed for scalability, enabling integration into mobile hydrogen (H2) generators, decentralized energy systems, and retrofitted refinery units. Compared to steam methane reforming, which emits significant CO2, catalytic reforming under optimized conditions can reduce greenhouse gas emissions and improve energy efficiency. The study quantifies heat flux density, thermal losses, and conversion efficiency to assess the environmental footprint of the H2 production process. Detailed analysis of heat transfer coefficients, temperature transitions, and flow dynamics provides practical guidance for reactor design and process optimization aimed at efficient H2 release. The use of supercritical fluids as coolants and reaction media enhances heat transfer performance and enables compact, high-throughput reactor systems for H2 generation. To ensure the reliability of conclusions, the study incorporates a rigorous error analysis framework. This includes deviations in temperature readings, pressure fluctuations, flow rate variability, and signal noise in data acquisition systems - all of which influence the precision of H2 yield assessments. The analysis informs recommendations for improving measurement accuracy and enhancing the reliability of H2 production evaluations. In summary, this work strengthens the scientific and engineering foundations of hydrogen (H2) production via catalytic reforming of hydrocarbons. The results are relevant to academic researchers, industry stakeholders, policymakers, and energy strategists seeking practical solutions for the hydrogen (H2) transition. The article concludes with a forward-looking perspective on the role of catalytic reforming in the emerging hydrogen (H2) economy. The methodology presented can be adapted to various hydrocarbon sources, reactor designs, and operational contexts, making it a versatile tool in global efforts to decarbonize energy systems and scale H₂ production. By demonstrating the potential of catalytic reforming under high-temperature and supercritical conditions, this study contributes to the strategic advancement of hydrogen (H2) technologies. It highlights the importance of interdisciplinary research combining chemical engineering, thermodynamics, materials science, and environmental analysis. The findings pave the way for future innovations in reactor design, catalyst development, and process integration, ultimately supporting the realization of a sustainable, hydrogen (H2)-powered future.

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