To obtain alkenes from coal, MTO/CTO is not the only option

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To extract alkenes from coal, MTO/CTO is not the only option. Author/Source: Yaha Coal Chemicals. Date: November 15, 2018. Clicks: 43. As 2018 comes to an end, looking back at the year, international crude oil prices remained on the rise. Prices of raw materials used in the production of alkenes such as methanol and propane surged due to various factors during the second and third quarters. In September, the price of ethane in the United States increased by 130% compared to the same period last year, owing to an imbalance between supply and demand. In contrast, in the domestic market, compared to other olefin feedstocks, coal prices remain stable due to policy regulation, which plays a key role in enhancing the competitiveness of coal-based olefins. With the rising prices of the raw materials used in the production of mainstream olefins, along with the steady increase in coal prices, the market landscape is quietly changing. Thanks to the significant cost advantage resulting from high oil prices, coal chemical industry has become a major driving force behind the growth of ethylene and propylene in China in recent years. According to a report by Yahuazheng Consulting, as of the end of October 2018, China had built 28 CTO/MTO units, with a total production capacity of 12.2 million tons per year – accounting for approximately 18% of the total olefin production capacity. In areas rich in coal resources, extending the industrial chain and increasing the added value of end products is undoubtedly crucial for enhancing the profitability of projects. For the existing CTO/MTO units, the product composition is approximately 36% ethylene, 44% propylene, 10% mixed C4, 10% C5, and fuel gas; the product structure is complex, requiring extensive separation processes. To achieve on-site conversion of raw materials, the process routes tend to become longer and more capital is required. Compared to ethylene, propylene has a wider range of available raw material sources; in particular, the new PDH production capacity added in China in recent years has provided more options for the propylene market. Maintenance of cracking units has a significant impact on ethylene prices, while the effect on propylene is relatively minor ； The expansion of ethylene production facilities is mainly concentrated in North America, China, and India, with limited new capacity additions in other regions. On the other hand, new production capacity is being added to propylene facilities in many areas, while a surplus in propane production capacity is becoming increasingly apparent. The data listed in the table above show the domestic capacity for MTO and propane dehydrogenation; the ratio of ethylene to propylene in the MTO products is calculated at 1:1.2. The total production capacity for ethylene is expected to be 5.97 million tons per year, while that for propylene will be 16.75 million tons per year; thus, the imbalance in the development of ethylene and propylene is evident. Therefore, a process route that produces ethylene in high proportions is needed. On November 13, 2018, the license agreement for the use of patented technology related to the production of 600,000 tons per year of ethanol from coal was signed at the Dalian Institute of Chemical Physics for the first phase of Xinjiang Tianye (Group) Co., Ltd.’s project aimed at producing 1.2 million tons per year of ethanol from coal. This move marked the beginning of an industrial era for ethanol production from coal on a million-ton scale in China, and it provided industrial support for the development of downstream products derived from ethanol, such as high-value chemicals like ethylene, vinyl chloride, styrene, and vinyl acetate. And the platform for this entire range of downstream products – ethylene – must be produced from ethanol. The ethanol dehydration to ethylene (ETE) technology provided by American Petron Scientech Inc., represented by Shanghai Diyang Chemical Import and Export Co., Ltd., offers enterprises a unique and more competitive route for producing ethylene from coal. Petron focuses on developing two patented technologies: the dehydration of ethanol to produce ethylene, and the oxidation of ethylene to produce ethylene oxide/ethylene glycol (EO/MEG). The ETE technology is currently in commercial use at more than a dozen companies around the world, with production capacities ranging from 20,000 tons to 600,000 tons; it can be used to produce various products such as EO/MEG and PE. This ETE technology accounts for 90% of the global market share. It is used in China’s only plant capable of producing 100,000 tons of ethylene through ethanol dehydration, and it is currently the only process in the world capable of producing polymeric-grade ethylene.