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I. Main uses of hydrogen Energy and the environment are the most critical issues related to the sustainable development of human society in the future. At present, the vast majority of the world’s energy needs are met by fossil fuels, which will ultimately lead to their depletion. Moreover, their use causes severe environmental pollution; therefore, the development and utilization of sustainable, pollution-free non-fossil energy sources is an inevitable trend in future energy development. Hydrogen has a wide range of applications, with the largest use being as an important raw material in the petrochemical industry, used in the production of synthetic ammonia and methanol as well as in hydrogenation reactions during oil refining. In addition, it is also used in fields such as the electronics industry, metallurgy, food processing, float glass production, fine chemical synthesis, and the aerospace industry. In the petroleum refining process, hydrocracking and hydrorefining of petroleum products require large amounts of hydrogen to be used as a reaction material ； Additionally, hydrogen is primarily used as a reducing gas in industries such as the electronics industry, metallurgy, and float glass production ； Used as fuel in the electronics industry ； In the aerospace field, liquid hydrogen is primarily used as the main fuel for rocket propulsion. In addition to the above conventional uses, an increasing number of research institutions are currently focusing on the development and utilization of hydrogen energy. Fuel cells that use hydrogen as an energy source have become a key focus of research worldwide. Since the late 1980s, due to the increasing problem of vehicle exhaust pollution, countries around the world have been competing to research and develop \"zero-emission\" fuel cell electric vehicles (FCEVs). Among these, proton exchange membrane fuel cell (PEMFC) vehicles, which are quiet and environmentally friendly, are considered the best alternative to traditional internal combustion engine vehicles. Currently, commercially viable PEMFC vehicles generally use a methanol reformer carried on board to supply fuel hydrogen. Thanks to new developments in fuel cell technology, hydrogen, as a fuel for fuel cells, exhibits an extremely broad potential market. The main methods for industrial-scale production of hydrogen include: 1) passing water vapor over heated coke to produce water gas, which is then separated to yield hydrogen; and directly vaporizing coal to produce gas, which is also separated to obtain hydrogen ； 2) Hydrogen can also be obtained through the catalytic decomposition of natural gas, as well as by separating the substances produced from the reforming of natural gas with water vapor; 3) Hydrogen production via the catalytic reforming of methanol; 4) Hydrogen production by water electrolysis; 5) Hydrogen production through the partial oxidation of heavy oil. Other methods include hydrogen production via ammonia decomposition. Currently, the technical methods for catalytic hydrogen production from methanol at home and abroad mainly include three types of hydrogen production techniques: methanol steam reforming, partial oxidation of methanol, and methanol decomposition. In the industrial production process, the hydrogen production technology based on methanol steam reforming is primarily used. The hydrogen production process via methanol steam reforming is favored by many manufacturing enterprises due to its advantages such as low investment costs, relatively low production expenses, advanced technology, easy separation of the produced hydrogen, and easy transportation of the raw material methanol; it has been widely applied in various industries across the country. II. Introduction to the catalytic hydrogen production process from methanol: In the catalytic hydrogen production process using methanol, the technologies with promising application prospects are hydrogen production via methanol steam reforming, hydrogen production via partial oxidation of methanol, and hydrogen production via methanol decomposition. The following provides a brief introduction to the three processes for catalytic hydrogen production from methanol. 1) Hydrogen production via methanol steam reforming: CH3OH + H2O → CO2 + 3H2; ΔH0298 = +40.5 kJ/mol. The raw methanol and deionized water are preheated and vaporized, then superheated to the reaction temperature. They pass through a catalyst bed where they undergo catalytic reforming to produce a mixture of hydrogen and carbon dioxide. This mixture is subjected to heat exchange, cooling and condensation, as well as washing, before being sent to a separation unit (such as a PSA system) for separation, resulting in hydrogen of high purity. Currently, Cu-ZnO/Al2O3 catalysts are primarily used in industry, offering advantages such as low reaction temperature, high reactivity, and high hydrogen selectivity. This process features a low reaction temperature (220–270°C), mild process conditions, low fuel consumption, a simple flow setup, and ease of operation; it has thus been widely applied in industry. 2) Hydrogen production via methanol partial oxidation (methanol partial oxidation and partial oxidative reforming): CH3OH + 1/2O2 → CO2 + 2H2, ΔH0298 = -192.3 kJ/mol; 2CH3OH + H2O + 1/2O2 → 2CO2 + 5H2, ΔH0298 = -384.6 kJ/mol. Methanol and/or deionized water, along with a certain proportion of oxygen, are preheated and vaporized, then superheated to the reaction temperature. They pass through a catalyst bed where they undergo catalytic reforming to produce a mixture of hydrogen and carbon dioxide. This mixture is then subjected to heat exchange, cooling and condensation, as well as washing, before being sent to a separation unit such as a PSA system for separation, thereby yielding hydrogen of high purity. Both the partial oxidation of methanol and the partial oxidation reforming for hydrogen production are exothermic reactions. The advantage of these reactions is that the heat required for the reaction itself can be generated through the partial oxidation of methanol; thus, no additional heating equipment is needed. Moreover, the oxygen required as a reactant can be obtained directly from the oxygen in air. These advantages **contribute to the miniaturization of methanol-based catalytic hydrogen production systems, laying the foundation for the practical application of this method in the future. Since research on the partial oxidation of methanol is still in its infancy, the range of catalyst systems available is limited, with only Cu-based and Pd-based catalysts existing to date. Copper-based catalysts are widely used in various methanol-to-hydrogen reactions due to their excellent catalytic performance for the methanol synthesis reaction. For Pd-supported catalysts, the partial oxidation of methanol can be carried out with a stoichiometric feed ratio, which is significant for making full use of CH3OH and achieving a high hydrogen yield per unit time. For the aforementioned Cu/Zn/Al catalysts, when O2/CH3OH is greater than 0.3, the selectivity of the reaction decreases significantly, with large amounts of by-products such as CO2 and H2O being produced. Therefore, Pd-based catalysts are more practically valuable than Cu-based catalysts and should be a key focus for future research. 3) Hydrogen production by methanol decomposition (CH3OH → CO + 2H2; ΔH0298 = +90.6 kJ/mol). Methanol is first preheated to vaporize, then superheated to the reaction temperature; it passes through a catalyst bed where a catalytic reaction takes place to produce a mixture of hydrogen and carbon monoxide. After separation, the desired products, hydrogen and carbon monoxide, are obtained. Carbon monoxide can be utilized in a wide range of applications; therefore, the methanol decomposition process for hydrogen production offers significant economic advantages, as it enables the production of two gas products, thereby **enhancing the sophistication of this process. The methanol cracking reaction can occur under normal pressure, with typical reaction temperatures ranging from 200 to 500°C. Low-temperature catalysts with high activity, high selectivity, and high stability play a crucial role in the hydrogen production process via methanol cracking. Commonly used methanol cracking catalysts include Cu-based catalysts and catalysts supported with precious metals. Among them, the Cu-based catalysts have the same properties as those used in methanol steam reforming for hydrogen production; therefore, the catalysts for methanol steam reforming can be directly applied to the methanol decomposition hydrogen production process.