Recent advances in the application of in situ X-ray diffraction techniques to characterize phase transitions in Fischer–Tropsch synthesis catalysts

Fischer–Tropsch synthesis (FTS), an important route for the conversion of syngas into high-value-added chemicals, often relies on Fe- and Co-based catalysts. Catalyst performance has been improved by promoters, supports, and optimization of the activation process; however, in-depth studies on the evolution of the phase during catalyst activation, reaction, and deactivation are still lacking. In situ X-ray diffraction (XRD) effectively reveals the phase evolution of catalytic materials in real time. In this review, the use of in situ XRD to elucidate the influence of activation mode, promoters, and supports on the phase evolution and performance of Fe- and Co-based catalysts is examined. The challenges and opportunities in studying the phase evolution of FTS catalysts using in situ XRD techniques are summarized and discussed, and theoretical guidance for the design of FTS catalysts is provided in order to promote their development.