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As a basic industrial raw material, ethylene plays a crucial role in the petrochemical industry. Its production volume is one of the important indicators reflecting the level of development of a country’s petrochemical industry. Except for North America and the Middle East, most countries and regions in the world, including my own country, use naphtha as a raw material and the steam cracking process to produce ethylene. This method is not only energy-intensive, generates large amounts of greenhouse gases, and is costly, but it also requires the use of petroleum as a raw material, thereby competing with valuable oil resources. Ethylene represents a very large market, worth around 330 billion pounds per year, which is equivalent to over 200 billion dollars per year. It is a valuable commercialized carbon dioxide-based chemical that can be combined to form transportation fuels. Ethylene can polymerize in groups of two, four, six, or eight molecules; one million molecules can form polyethylene, while 500,000 molecules result in aramid, and so on. Today, ethylene molecules come from oil and are produced through a process called steam cracking. This is a major energy consumer and a significant source of CO2 emissions in the chemical industry, as it involves an endothermic reaction. To produce ethylene from naphtha, it must be mixed with superheated steam at 800 degrees Celsius, and physical forces are essentially used to break the carbon-carbon bonds. It is a robust technology that comes at the cost of petroleum consumption; large amounts of heat must be generated through combustion to facilitate endothermic chemical reactions. In terms of its energy footprint, the production of 1 kg of polyethylene results in the emission of 2 kg of CO2. There are two routes for producing ethylene from natural gas (whose main component is methane): the direct method and the indirect method. Compared to the lengthy and complicated process of the indirect method, the direct method can convert methane into ethylene in just one step, offering high economic value and thus being highly attractive. After more than 30 years of efforts by the chemical industry, this has finally become a reality—abundant and inexpensive natural gas can be directly converted into ethylene, a major basic chemical raw material used worldwide. Methane is abundant because it is the main component of natural gas, and there are large reserves of natural gas in many parts of the world. However, the process of producing ethylene via methane coupling still needs to be improved; the yield of ethylene using current catalyst technologies is not sufficient to enable the rational commercialization of this process. To make the direct conversion of methane into chemicals economically viable, further advancements in catalysts, process technologies, and separation methods are still needed. To reduce dependence on oil, countries are conducting research on the production of olefins from natural gas, whose main component is methane. The routes for producing ethylene from natural gas are divided into direct and indirect methods. Compared to the lengthy and complicated process of the indirect method, the direct method can convert methane into ethylene in just one step, offering high economic value and thus being highly attractive. However, since the selective activation and directed conversion of methane represent world-class challenges and are regarded as the \"Holy Grail\" of the entire chemical industry, from the 1980s to the early 2000s, the academic community has failed to develop an industrially viable process for directly converting methane into ethylene. Dow Chemical’s startup plan includes several routes for producing chemicals from alternative feedstocks, including the syngas route. The production of olefins from syngas has been developed, but it is capital-intensive. Avoiding syngas and directly converting methane into olefins as an industrial goal has been proposed for several years. Further development is underway to make it technically feasible, using viable processes to couple methane to produce ethylene, which would offer significant advantages for tapping into remote natural gas resources. Dow Chemical Company hopes to develop a process for converting methane into ethylene within the next 10 years. The reaction known as oxidative coupling of methane (OCM) is a process that the petrochemical industry has been trying to develop for over 30 years; however, the drawbacks of conventional catalyst technologies have made it impossible to achieve economic viability. The search for industrially viable OCM methods has lasted for decades, but past efforts have been unsuccessful due to the high temperatures required to activate methane, which reduces the selectivity of the reaction. Using many of the catalysts studied previously, the methyl radicals remain on the catalyst surface before being converted into the desired ethylene product, and are typically oxidized non-selectively to CO2. The use of heterogeneous and homogeneous catalysts for methane oxidation coupling (OCM) has achieved some success, but it has not been commercialized due to insufficient thermodynamics, selective reactivity, and yields, which render it uneconomical at present. According to Ciluria Corporation, the technology it has developed is expected to help the petrochemical industry save hundreds of billions of dollars per year in terms of raw material and operating costs. Natural gas resources continue to increase, while the available oil supply in the world is becoming increasingly expensive. Although methane in natural gas will continue to play an important role as a clean-burning alternative to coal for power generation, its high abundance (more than 10 times that of ethane in natural gas) and lower price (about half that of ethane) have spurred efforts to utilize methane directly as a feedstock for producing ethylene and other chemicals, rather than burning it as fuel. If successful, it could make the direct production of ethylene from methane a commercially viable method, which is expected to mark a turning point for the chemical and petroleum industries. Many companies are engaged in research and development to commercialize the technology for converting methane into ethylene; Chevron, ExxonMobil, Shell, and BP all hold extensive patent portfolios related to this technology. Several large chemical companies also possess intellectual property in this area (BASF, Lubrizol, Saudi Basic Industries Corporation, GE, Honeywell, etc.). The Polish Research Laboratory of Fertilizers is also interested in methane oxidative coupling (OCM). The key to breakthrough lies in the catalyst. In 2010, Siluria creatively utilized biological templates to precisely synthesize nanowire catalysts. By employing high-throughput technologies, the company identified the appropriate elemental composition from a large number of candidate catalysts, ultimately developing an industrially viable catalyst for the direct conversion of methane into ethylene. This catalyst can efficiently catalyze the conversion of methane to ethylene at 5–10 atmospheres of pressure, at temperatures lower than those used in conventional steam cracking methods (200°C–300°C), with an activity more than 100 times that of traditional catalysts. The reactor designed by Siluria Company is divided into two parts: one part is used to convert methane into ethylene and ethane, while the other part is used to crack the by-product ethane into ethylene; the heat required for the cracking reaction comes from the heat released during the methane conversion reaction. This design allows the reactor to be fed either natural gas or ethane, while maximizing energy savings. Studies indicate that catalysts synthesized using nanotechnology-based approaches to convert natural gas into ethylene hold promise as an alternative to crude oil steam cracking. On December 10, 2010, the American company Siluria Technologies announced that it had developed a synthesis method that allows for the adjustment of the morphology of the catalyst surface, thereby enabling high-performance methane oxidation coupling (OCM) reactions at low temperatures. By employing synthetic molecular biology within the realm of industrial chemistry, Ciluria’s catalyst synthesis process involves using proteins on the surface of genetically modified phages (viruses caused by bacteria) as catalytic materials that serve as active centers for the formation of growing nanowire nuclei. By allowing these catalyst nanowires to grow on engineered biological templates, Ciluria can achieve specific crystal structures and surface morphologies, without forming the conventional crystals of this material. Furthermore, the new crystalline structure can increase the number of catalyst active centers with unique properties, which are crucial for the selectivity and yield required in economically viable OCM processes. This catalyst material is a proprietary transition-metal-containing metal oxide, designed to be compatible with existing petrochemical industry infrastructure. Siluria has developed a library of compounds with a wide range of crystalline structures, and tested their performance in catalyzing the OCM reaction. The technical advantages of the direct ethylene production process from natural gas (new route) developed by Siluria Company lie in five main aspects: lower costs compared to traditional ethylene production via naphtha cracking, reduced greenhouse gas emissions, energy savings, and high economic value ； Ethylene can be further converted into liquid fuels, thereby further enhancing the economic value of the entire process ； The requirements for raw materials are not stringent; methane can come from natural gas or biomass, and the oxygen source can be pure oxygen, oxygen-enriched air, compressed air, etc ； It can make use of existing ethylene production facilities and recovery equipment, resulting in low retrofit costs ； It holds significant strategic value due to its abundant natural gas resources. In addition to its impact on the olefin industry, the new route will also affect the production of liquid fuels including gasoline, diesel, and aviation fuel. Ciluria has also developed a technology for producing liquid fuels from ethylene, which provides an additional route for manufacturing liquid fuels from natural gas. Compared to the current route based on the Fischer-Tropsch process, Ciluria’s approach eliminates the need for energy-intensive Fischer-Tropsch synthesis, resulting in cost savings of 25% to 30% merely in terms of investment costs. Other companies that have achieved initial success in developing direct conversion of natural gas to ethylene include: research on natural gas-to-ethylene conversion at Northwestern University and the University of Virginia; research by Syntroleum Corporation on converting natural gas into acetylene and then into ethylene; development by Honeywell International Inc. in the United States of a technology for producing ethylene from methane in natural gas; and research at the Dalian Institute of Chemical Physics in China on the efficient conversion of methane. The successful development of new routes for producing ethylene directly from natural gas could bring about significant changes to the traditional ethylene industry that relies on petroleum as a raw material. It is recommended that China draw on the successful experience gained from the development of methanol-to-olefins production during the 12th Five-Year Plan period, and include research on direct conversion of natural gas into ethylene in the relevant development plans for the 13th Five-Year Plan. Organize research institutions and petrochemical enterprises to carry out R&D cooperation, so as to facilitate the prompt transformation of basic research findings into industrial production. This will help overcome the current bottleneck in raw material supply for the ethylene industry, reduce production costs, and enhance the competitiveness of China’s ethylene industry and its downstream sectors. Information source: Qian Bozhang, “Energy Conservation in the Petroleum and Chemical Industries”