On the Deactivation\nand Regeneration of Metallosilicate\nCatalyst for Ethanol to Butadiene: A Comparative Study for Lewis Acid

Zr-β zeolites have emerged as promising catalysts\nfor the\nconversion of ethanol to butadiene due to their Lewis acidity. Despite\nthis potential, inevitable deactivation of the catalyst poses a significant\nbottleneck for its industrial application. Currently, there have been\nseveral reports on catalyst deactivation regarding the mechanism and\nregeneration. However, a systematic study of the relationship between\ncatalyst acidity and the deactivation process, as well as the corresponding\nregeneration process, has yet to be conducted. In this study, we conducted\na detailed investigation into the variation of catalyst texture properties\nand acidity during the regeneration for Zr-β catalysts and clarified\nthat the carbon deposition and regeneration are directly related to\nthe strong Lewis acid sites. Additionally, we evaluated various methods,\nincluding liquid- and gas-phase calcination regeneration and optimized\nregeneration conditions. Under the conditions of an air atmosphere,\na regeneration temperature of 450 °C, a regeneration time of\n6 h, and a cycle period of 24 h, the catalytic activity could be sustainably\nrecovered.