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This post was last edited by liaifeng on 2018-8-4 at 18:07. Breaking the supply-demand balance: Coal-to-oil companies can now produce α-olefins. Author/Source: Huahua Network – Coal Chemical Industry. Date: 2018-02-26. Views: 15. In June 2015, Shanxi Lu’an Group used the α-olefins produced by its coal-to-oil facility, along with traditional catalysts, to establish China’s first demonstration plant capable of producing 15,000 tons per year of coal-based polyα-olefin synthetic oil (PAO), thereby manufacturing high-viscosity polyα-olefin synthetic oil. This is the first coal-based poly-α-olefin synthetic oil production facility in the country. A relevant official from Shanxi Lu’an Taihang Lubricant Co., Ltd. explained that poly-α-olefin synthetic oil has a high viscosity index and low volatility, and boasts advantages such as strong wear resistance, oxidation resistance, cleanliness, and dispersing properties. Lubricants formulated with polyalpha-olefin synthetic oil can achieve an oil change interval of 20,000 kilometers for gasoline engines and 60,000 kilometers for diesel engines; they also provide excellent protection for the engine. The performance in terms of cold-start capability, climbing power, and engine noise control is **far beyond expectations**. On November 10, 2017, Lu’an Group commenced construction of an upgraded version of coal-based poly-α-olefin synthetic oil – a facility with an annual production capacity of 3,000 tons that utilizes a metallocene catalysis process jointly developed by Lu’an Group and the Shanghai Institute of Advanced Technology of the Chinese Academy of Sciences. This facility takes advantage of Lu’an Group’s resources in coal-to-α-olefin conversion as well as its expertise in olefin separation and purification techniques, with operations scheduled to begin in September 2018. It is reported that metallocene coal-based polyα-olefin synthetic oil can use α-olefins ranging from C8 to C12 or from C8 to C12, as compared to traditional polyα-olefin synthetic oil; this makes the raw materials available in larger quantities. The resulting product features a more regular side-chain structure, a higher viscosity index, and a lower pour point. Polyalpha-olefin synthetic oil is a high-performance base oil for premium lubricants. So, what are the advantages of coal-based poly-α-olefin synthetic oil? To this end, the reporter conducted an investigation. It is said that polyalpha-olefin synthetic oil is a synthetic oil produced by the polymerization of alpha-olefins (C8-C12) in the presence of a catalyst, followed by hydrogenation saturation. Compared with other types of synthetic oils, polyalpha-olefin synthetic oils have a high viscosity index, a low pour point, high oxidation stability, and low volatility. Moreover, the raw material components and degree of polymerization can be adjusted as needed to produce products with a wide range of viscosities. It has low evaporation loss and low volatility, resulting in fewer components being lost during high-temperature operation. In industrial equipment, gear oils made from polyalpha-olefin synthetic oils can help save energy, reduce downtime, improve energy efficiency, and lower energy consumption. Although the use of polyalpha-olefin synthetic oils is not yet widespread in China, as the design technology of automobile engines improves and more imported vehicles as well as various equipment become available, it is expected that demand for polyalpha-olefin synthetic oils in the domestic market will increase at a rate of 3.5% per year. The traditional production of polyalpha-olefin synthetic oils relies on the olefin oligomerization method, which involves using low-molecular-weight olefins such as ethylene as raw materials, oligomerizing 1-decene, further oligomerizing the resulting 1-decene, and then hydrogenating the oligomers to achieve saturation. For a long time, the production of poly-alpha-olefin synthetic oils with high viscosity indices has faced a series of problems, such as the high selectivity required of catalysts. The School of Materials at East China University of Science and Technology has carried out scientific research in collaboration with the Daqing Chemical Research Center of China National Petroleum Corporation for over 10 years, developing new methods for catalyst molecular design and structural control, thereby achieving high selectivity and high activity for advanced α-olefins. This achievement also won the First Prize for Scientific and Technological Progress in Shanghai in 2016. However, the production of polyalpha-olefin synthetic oils via domestic oil routes still faces many problems. A relevant official from Sinopec Lubricants Co., Ltd. stated that currently, 94% of poly-α-olefin synthetic oils in China are imported, while 6% is produced domestically using the paraffin cracking method. Since all domestically produced poly-α-olefin synthetic oils are made from different waxy feedstocks (including various waxy oils and oil-containing waxes), and the paraffin cracking reaction must take place at high temperatures, the resulting products contain impurities such as aromatic compounds, alkanes, and dienes, resulting in a relatively complex composition. Compared with foreign products, domestic poly-α-olefin synthetic oils fall far behind in terms of viscosity index, low-temperature viscosity, and thermal oxidation stability. Today, this weak link in the domestic market has been filled by Lu’an Group’s metallocene coal-based polyα-olefin technology. Industry professionals have expressed their admiration for this company’s technology. Xu Jian, a doctor at the Shanghai Advanced Institute of the Chinese Academy of Sciences, said that due to limitations in production processes and catalysts, traditional poly-alpha-olefin synthesis oil technologies are unable to produce low-viscosity products with viscosity grades of 2, 4, 6, and 8 square millimeters per second, which are the most in demand in the market. Moreover, the quality of the oil produced is far inferior to that of oil products manufactured by internationally renowned oil companies. Coal-derived poly-α-olefin synthetic oil catalyzed by metallocenes can **improve the quality of the oil product**. Li Tonglin, a professor-level senior engineer at the R&D institute of Sinopec’s Yanshan Branch in Beijing, told reporters that due to constraints related to key raw materials, the production of domestically-made poly-α-olefin synthetic oil has not yet been put into industrial use. The development of coal-to-oil technology has broken the tight supply and demand situation for raw materials used in the synthesis of polyalpha-olefin oils. Coal-to-oil plants can produce α-olefins that cannot be produced by petrochemical plants. Jiang Jiansheng, senior advisor at Inner Mongolia Yitai Group, told reporters that a 1 million tons per year coal-to-oil facility is capable of producing 25% α-olefins, as well as about 8% of 1-decene. α-olefins are a relatively scarce chemical raw material; using hydrogenation to produce naphtha and diesel is both hydrogen-intensive and uneconomical. Separating α-olefins to produce polyα-olefin synthetic oil can **increase the added value of the product. However, although the demonstration plant for coal-based polyα-olefin synthetic oil operated by Shanxi Lu’an Group has only just started construction, reporters have learned that several coal-to-oil companies are considering such projects; for example, Shaanxi Future Energy Chemical Co., Ltd. is also planning to set up a plant for producing polyα-olefin synthetic oil at a capacity of 50,000 tons per year. Industry experts warn that polyalpha-olefin synthetic oil is a high-grade base oil, and its usage volume is not large; if everyone starts using it, there will definitely be a surplus.