Zhidong Yang, Liehui Zhang, Yuhui Zhou, Hui Wang, Lichen Wen, Ehsan Kianfar
July 4, 2020
Light olefins such as ethylene, propylene and butylene are mainly used in the petrochemical industry. Due to the growing need for light olefins in the industry and the future shortage of petroleum resources, the process of converting methanol to olefins (MTO) using non-oil sources has been considered as an alternative. Coal and natural gas are abundant in nature and the methods of converting them to methanol are well known today. Coal gasification or steam reforming of natural gas to produce synthetic gas (CO and hydrogen gas) can lead to methanol production. Methanol can also be catalytically converted to gasoline or olefins depending on the effective process and catalyst factors used. Due to the use of crude methanol in the MTO unit and because the feed does not require primary distillation, if the MTO unit is installed alongside the methanol unit, its capital costs will be reduced. The use of methanol can have advantages such as easier and less expensive transportation than ethane. Among the available catalysts, SAPO-34 is the most suitable catalyst for this process due to its small cavities and medium acidity. One of the problems of MTO units is the rapid deactivation of SAPO-34, which can also be affected by the synthesis factors, so it is possible to optimize the catalyst performance by modifying the synthesis conditions. In this article, we will introduce the MTO process and the factors affecting the production of light olefins.