Recently, Liu Zhongmin and Zhu Wenliang, the National Engineering Laboratory for Methanol to Olefins of the Institute of Chemical Physics and Physics, Chinese Academy of Sciences, made new progress in the study of coupling aromatics with methanol and carbon monoxide. The study was published in the German Journal of Applied Chemistry (Angew. Chem. Int. Ed.), and was named Hot Paper.
Aromatic hydrocarbons (benzene, toluene, xylene) are important basic chemical raw materials, and their production and scale are second only to ethylene and propylene. At present, large-scale industrial production of aromatic hydrocarbons is realized by a naphtha-based aromatics unit. China's polyester industry is developing at a high speed, the consumption of aromatics is rising rapidly, and the supply gap is increasing year by year. Therefore, accelerating aromatics production and developing new aromatics technologies are of vital importance to the healthy development of China's polyester industry. Due to the shortage of China's petroleum resources, coal is abundant. The clean and efficient supply of energy and chemicals has become an urgent problem in the development of the country. The development of chemical technologies such as methanol-based aromatics is of great significance for reducing the external dependence of crude oil and ensuring national energy security, and has a broad market prospect. The ZSM-5 molecular sieve with selective shape is often used as the catalyst for the reaction of methanol to aromatics. Because of the hydrogen transfer reaction, the formation of aromatic hydrocarbons is accompanied by the formation of alkane, and the selectivity of aromatics needs to be further improved.
In this work, the researchers found that on the pure metal-modified pure H-ZSM-5 molecular sieve, methanol and carbon monoxide can be coupled to obtain about 80% aromatic selectivity. In addition, the work also proposed a brand new Aromatization mechanism: carbonylation of methanol with carbon monoxide on H-ZSM-5 to form a carbonyl intermediate, and then reacting with an olefin to form a cyclopentenone intermediate, dehydration to obtain an aromatic hydrocarbon. By 13C nuclear magnetic and isotope tracer The method can prove that carbon carbon of carbon monoxide can enter into aromatic hydrocarbons and cyclopentenone intermediates. Since carbon in carbon monoxide enters aromatics, it can directly produce aromatics relative to methanol, which can increase the yield of aromatics and improve industrialization. The economics of the process.
The above research work is supported by the National Natural Science Foundation.
