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Another breakthrough in coal-to-aromatics technology, but industrialization is still on the way. Author/Source: Date: 11-06-2017. Clicks: 11. Recent news indicates that in October, the methanol conversion team at the **Key Laboratory of Coal Conversion, Shanxi Institute of Coal Chemistry, Chinese Academy of Sciences, successfully carried out a pilot-scale test for converting methanol into aromatics on a scale of 100 tons at the pilot plant in Xiaodian, Taiyuan. It is reported that this test was conducted on a self-developed 100-ton-scale pilot plant for methanol-to-aromatics production. Following the installation and commissioning of the plant as well as equipment optimization, the test was successfully carried out on the first attempt. During the testing period, not only was the entire production process streamlined, but the catalysts developed independently as well as the process conditions were tested and optimized, enabling automatic control of operating parameters such as feed and discharge flow rates, temperature, and pressure. To date, the unit has operated stably at full capacity for 500 hours, producing qualified aromatics; all technical parameters have met and exceeded those of similar domestic technologies (methanol conversion rate of 100%, liquid hydrocarbon yield of 31%, and aromatics selectivity of 83%). The methanol-to-aromatics (MTA) technology developed by the Shanxi Coal Chemistry Institute has received support from the Chinese Academy of Sciences’ strategic pilot science and technology project titled “Key Technologies and Demonstrations for Clean and Efficient Hierarchical Utilization of Low-Rank Coals”, as well as from relevant enterprises; it employs a two-stage continuous flow fixed-bed reaction process that was developed independently. Through long-term perseverance and relentless research, the team focused on methanol directed conversion technologies, working on aspects such as reaction mechanisms, catalyst design, and process optimization. They have published over 20 papers in journals including Chem. Soc. Rev., J. Catal., ACS Catal., Chem. Commun., and Green Chem. On this basis, they developed new catalysts and corresponding process routes for producing high-value aromatic compounds from coal-based methanol, achieving breakthroughs in the selectivity of aromatic products, the stability of reaction operations, and the scale of the technology. The successful completion of the 100-ton-scale pilot plant for methanol-to-aromatics production and the stable operation of the facility have further accelerated the industrialization of this technology. The conversion of methanol into aromatics is a process in which methanol serves as the raw material and is transformed into aromatic products using molecular sieve catalysts. It represents an effective process for utilizing coal or natural gas as alternatives to petroleum resources to produce aromatics such as benzene, toluene, and xylene. This approach is significant for alleviating shortages of aromatic resources and extending the industrial chains related to coal chemistry and natural gas chemistry. The industrialization of coal-based aromatics is still in progress. Although the conversion of coal to aromatics via methanol is one of the current trends in the development of the coal chemical industry. However, unlike the production of olefins, coal-based aromatic compounds are still making slow progress toward industrialization. In 2010, Tsinghua University was the first in the world to successfully develop the fluidized-bed methanol-to-aromatics process technology. From 2011 to 2013, Tsinghua University collaborated with Beijing Huadian Coal Industry Group to build and operate an industrial pilot plant for the production of aromatics from methanol using a fluidized-bed process, with a capacity of 30,000 tons per year; simultaneously, a process package with a capacity of 600,000 tons per year was developed. On April 18, 2014, the world’s first industrial demonstration project for producing aromatics from coal via methanol, with an estimated total investment of 36 billion yuan, was launched in Yulin, Shaanxi. This project involves Huadian Coal Industry Group’s facility capable of producing 3 million tons of coal-to-methanol per year, 1.2 million tons of aromatics via fluidized-bed methanol conversion per year, 1 million tons of mixed aromatics used to produce p-xylene per year, 1.6 million tons of purified terephthalic acid per year, and 600,000 tons of polyester-related products per year. The first phase of this project entails the production of 1.2 million tons of coal-to-methanol per year, 600,000 tons of methanol-to-aromatics per year, 500,000 tons of p-xylene per year, and 800,000 tons of purified terephthalic acid per year. Regrettably, more than three years have passed since the project began, and it is still in the preliminary stages; construction has not yet actually started. On the one hand, this is due to the numerous and complicated approval procedures required for the project, including nearly 20 different types of approvals such as project safety assessments, environmental impact assessments, energy assessments, land use permits, rights to extract coal from associated mines, water use rights, etc., as well as the need to address various aspects related to the introduction of specialized technologies one by one ； On the other hand, the sharp decline in international oil prices over the past two years, along with their prolonged stay at low levels, has significantly weakened the cost advantage of producing aromatics from coal via methanol. Coupled with the decline in the profitability of power companies over the past two years, the senior management of HuanDian Coal Industry Group has had to adopt a very cautious approach toward this first demonstration project, which involves substantial investment. Nevertheless, the industry remains optimistic about the prospects of using coal to produce aromatics via methanol. It is understood that China Tianchen Engineering Company previously conducted an economic assessment of coal-based aromatic compounds projects, concluding that when international oil prices reached 70 dollars per barrel, the corresponding price for p-xylene was 7,565 yuan per ton. At this point, the internal rate of return for the HuanDian Yulin project can reach 11% (pre-tax). According to predictions by Yaha Consulting, in the coming years, international crude oil prices will fluctuate between $50 and $90 per barrel, resulting in a duty-paid import price for p-xylene of 5,905 to 9,226 yuan per ton. In other words, over the next few years and for an even longer period, even if international oil prices remain at a low level of 50 dollars per barrel, the annual profit of the HuanDian Yulin project will still exceed 200 million yuan. This is still a prediction assuming that p-xylene is the final product. In fact, since the Huadian project has now evolved into a fully integrated industrial chain with complete upstream and downstream links, there are fewer vulnerable points and the overall costs are lower, resulting in higher product profit margins and project returns. The calculations carried out jointly by the Petroleum and Chemical Industry Planning Institute and China Tianchen Engineering Company also show that coal-to-aromatics has strong competitiveness and good profitability. The report shows that when the international crude oil price is 80 dollars per barrel, for the same million-ton-scale aromatic compound production facility, the comprehensive costs of producing aromatics from naphtha, from methanol, and from coal-based methanol are 7,822 yuan per ton, 7,921 yuan per ton, and 5,455 yuan per ton respectively. The cost advantage of coal-based methanol for producing aromatics is obvious.