Mixed MFI-mord zeolite reactivation study in micro structured reactor in methanol to hydrocarbons transformation reaction

Restoring the activity of catalytic systems is an important scientific and technical problem. To date, a large number of catalyst regeneration methods have been developed, including treatment with ultrasound, acids, alkalis, hydrogen, air, etc. However, to determine the necessary technological parameters, it is necessary to conduct experiments. Catalysts for the transformation of methanol into hydrocarbons are characterized by a significant tendency to lose their activity during operation. The main method for restoring their activity is oxidation in an air stream, however, it is possible to restore a different number of acid sites, both as a result of the retention of a certain amount of residual carbon, and as a result of thermal destruction of acid sites. In this connection, the determination of the optimal modes of zeolite thermal oxidation makes it possible to ensure the maximum residual activity of the regenerated catalyst. The article presents the results of studying the activity recovery of the MFI-MORD zeolite by the method of temperature-programmed oxidation at a sample heating rate of 5℃/min, 10℃/min, 20℃/min. Heating at 5℃/min leads to the recovery of the minimum number of acid sites, as well as the minimum value of the residual activity of the transformation of methanol into hydrocarbons of 0.121 kg(Hc)/(kg(Cat)×h). Increasing the heating rate to 10℃/min leads to the restoration of the maximum number of active centers and the achievement of a maximum residual activity of 0.21 kg(Hc)/(kg(Cat)×h). And an increase in the heating rate to 20℃/min leads to a decrease in the number of acid sites and a decrease in the residual catalytic activity of 0.142 kg(Hc)/(kg(Cat)×h). The decrease in the number of acid sites and residual activity at the highest heating rate of the sample may be due to the thermal destruction of active sites during rapid heating.