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This post was last edited by liaifeng on 2018-7-29 at 15:34. α-Olefins are key to producing high-quality polyethylene; CNPC has made breakthroughs in α-olefin technology using its own intellectual property. Author/Source: Yaha Coal Chemical Industry. Date: 2018-03-01. Clicks: 10. • α-Olefins are important comonomers for polyethylene, and it is estimated that by the end of 2021, China’s consumption of α-olefins for LLDPE and HDPE will reach 850,000 tons； •The production technology of α-olefins, particularly high-carbon α-olefins, will be key to high-end polyethylene products such as mPE, POE, and materials designed for advanced applications ； •The First China Ethylene Downstream New Technologies and Market Forum will be held in Wuxi from March 29-30, 2018. Experts from CNPC will attend the conference and present the progress made in the development of α-olefin technologies by CNPC. Using α-olefins (such as 1-butene, 1-hexene, 1-octene, etc.) as comonomers in the production of polyethylene (PE) can improve its machinability, flexibility, transparency, tensile strength, impact strength, creep resistance, and other properties. Typically, the average content of α-olefin copolymer monomers in LLDPE is around 8%-10%, whereas in HDPE it is 1%-2%. By the end of 2016, China’s LLDPE and HDPE production capacities were approximately 7.7 million tons per year and 7.65 million tons per year, respectively, while the actual production volumes for that year were 6.52 million tons per year and 5.65 million tons per year, respectively. Calculated at addition levels of 8% and 1% respectively, the consumption of α-olefins by LLDPE and HDPE is 520,000 tons per year and 56,500 tons per year, respectively. Yahua Consulting estimates that by the end of 2021, China’s LLDPE and HDPE production capacities will reach 11 million tons per year and 12 million tons per year respectively, with corresponding production volumes of 9.3 million tons and 8.9 million tons for that year. The consumption of α-olefins by these two types of polyethylene will be 750,000 tons per year and 89,000 tons per year respectively, resulting in an overall consumption of 849,000 tons per year – a 45% increase compared to the end of 2016. http://img.yf116.cn/image/img/20180301/163595783917.jpg China is a major producer and consumer of polyethylene. According to Yahuazheng Consulting, in 2017 China’s polyethylene production capacity was around 17.4 million tons per year, with production amountsing to about 15.8 million tons, imports at around 11.8 million tons, and apparent consumption at approximately 28.4 million tons. China’s polyethylene industry has seen a competitive landscape shaped by both the petroleum-based route and the coal-based routes (CTO/MTO). http://img.yf116.cn/image/img/20180301/165305793025.jpg In recent years, China’s demand for polyethylene has seen steady overall growth, along with an increasing diversification and upgrading of its structure. Demand for high-end polyethylene products, represented by metallocene polyethylene (mPE), polyolefin elastomers (POE), and materials designed for high-end applications, is growing rapidly. mPE is a copolymer produced from ethylene and α-olefins using metallocene catalysts. It is expected that demand for mPE in China will grow at an annual rate of over 10% during the 13th Five-Year Plan period, reaching more than 800,000 tons by 2020. POE generally refers to polyolefin elastomers formed by the copolymerization of ethylene/α-olefins; typically, POE denotes the copolymer of ethylene/1-octene (with a mass fraction of 1-octene exceeding 20%). In high-end polyethylene, it has become an industry trend and necessity to use 1-hexene and 1-octene, which have longer carbon chains, as comonomers in place of 1-butene; therefore, the production technology for α-olefins, especially those with higher carbon counts, will be key to advancing polyethylene products to higher quality levels. The main methods for producing α-olefins include ethylene oligomerization, paraffin cracking, extraction separation, fatty alcohol dehydrogenation, and internal olefin isomerization; among these, ethylene oligomerization is the most prominent industrial method. Currently, the production technology for high-carbon α-olefins is primarily in the hands of foreign companies and is not transferred to Chinese enterprises. The \"Implementation Plan for the Industrialization of Key Technologies in New Materials\" under the \"Three-Year Action Plan to Strengthen the Core Competitiveness of the Manufacturing Sector (2018–2020)\") specifies that the polycondensation process can be used to produce high-carbon α-olefins with an carbon chain length of eight or more atoms, with industrial projects requiring a production capacity of over 50,000 tons per year per unit facility. Domestic companies, represented by CNPC, are also making some breakthroughs in the development of α-olefin production processes. For example, the Daqing Petrochemical Research Institute of CNPC completed pilot-scale tests on a new catalyst system for 1-octene, as well as studies on the synthesis of 1-octene and 1-eicene via ethylene oligomerization; a series of research projects on α-olefin catalysts passed the acceptance assessment organized by CNPC’s Refining and Petrochemical Technology Research Center ； The pilot-scale project for the new catalyst system for 1-octene development aimed at creating a catalyst for the high-selective oligomerization of ethylene to produce 1-octene; appropriate process conditions were determined in a pilot-scale batch reactor, and conceptual design as well as economic and technical evaluations were carried out, laying a technical foundation for pilot-scale studies ； In 2017, the first industrial-scale test project for CNPC’s 20,000 tons per year hexene-1 production facility, carried out jointly by Dushanzi Petrochemical, the Petroleum Chemical Research Institute, Kunlun Engineering Company, Daqing Petrochemical, as well as the East and South China Chemical Sales Companies, was completed successfully; this project enabled the acquisition of the technology for producing hexene-1 through the polymerization of ethylene.