Optimization of Sustainable Aviation Fuel Production through Experiment-Driven Modeling of Acid-Catalyzed Oligomerization

Abstract

To reduce the aviation industry’s greenhouse gas emissions, sustainable aviation fuel (SAF) is needed. Therefore, a methanol-to-SAF process comprising (i) methanol to olefin (MTO), (ii) olefin oligomerization, and (iii) olefin hydrogenation reaction steps is a promising route. The olefin oligomerization step is responsible for resulting SAF properties and needs to be optimized in concert with the previous MTO step. For this purpose, a kinetic model using a total of seven kinetic parameters was designed from a limited number of experimental measurements, allowing us to successfully describe the oligomerization reactivity of various olefin mixtures over an acid catalyst in flow. This inexpensive model predicted optimal reaction conditions and feed compositions, resulting in product mixtures with properties matching those of conventional Jet-A1 aviation fuel. To maximize SAF-range products, a feed composed of C₄ and C₅ olefins is most desirable, while controlled C₃, C₆, and C₇ olefin cofeeding and C₄/C₅ olefin feed ratio are required to finely tune the SAF product composition. This modeling approach allows for efficient process optimization directed toward the synthesis of SAF with controlled properties and composition. Additionally, precise MTO–olefin compositions can be predicted for the optimal production of high-quality SAF, pointing toward the development of an efficient overall methanol-to-SAF process.