Development of shape selectivity theory of methanol-to-olefins reaction over small-pore zeolite molecular sieves

The methanol-to-olefins reaction is regarded as an important technology capable of meeting today’s rising demand for light olefins. The regioselective confinement effect of small-pore, cage-type zeolites on hydrocarbon pool intermediates results in strong shape selectivity determining the product olefin distribution. Despite decades of effort, a direct correlation between zeolite cage topologies and olefin selectivity distributions had remained elusive. The cage-defining ring theory is the first general catalytic shape selectivity theory that can predict the selectivity distribution of product light olefins from the given crystallographic information of the small pore zeolite catalysts. This article outlines the development procedure of the cagedefining ring theory. To aid readers’ comprehension, brief introductions to the structures and properties of zeolites and related molecular sieves, which are an important class of ceramic catalysts, are also provided.