(734b) Multi-Functional Composite Catalyst Materials for the Generation of Propylene from 2-Butene

The petrochemical industry is facing numerous challenges in addressing the increasing global demand for important commodity chemicals, such as propylene and propylene derivatives. These changes in the market demand are driven in large part by a rise in population growth and an increase in consumer buying power, particularly in places like China, India, and Latin America. In order to meet future demand, industrial efforts are focused on identifying low value or underutilized refinery streams that could be modified and upgraded in order to produce propylene ‘on-purpose’. Commercial routes for ‘on-purpose’ production of propylene exist currently, but they rely on the cross metathesis of 2-butene with ethene, which is also an essential commodity chemical. Recently, there has been growing industrial interest in the development of heterogeneous metathesis catalysts that can produce propylene utilizing 2-butene as the starting feedstock. The reaction relies on 2-butene isomerization to 1-butene followed by cross metathesis in order to produce propylene. However, this reaction typically generates undesired heavy by-products, such as pentenes and hexenes, which can be broken using a separate reaction with a cracking catalyst. Herein, we discuss the development of a dual-functional catalyst that incorporates metathesis and cracking functionalities within a single material, eliminating the need for multiple reactors and improving the process economics. The material combines group 6 metal oxides on silica supports and CHA or MFI-type zeolite crystals. We describe a variety of processing techniques, including a continuous aerosol flow reactor and a conventional spray dryer, in order to generate catalyst materials with tunable chemical composition and physical properties, which are characterized via conventional techniques. The materials are then tested in a fixed-bed reactor with a 2-butene feed stream and are optimized for maximum conversion and selectivity towards propylene.