Catalytic activity of regenerated catalyst after the oxidation of 1,2-dichloroethane and trichloroethylene

• Feasibility to regenerate H-zeolites aged by different Cl-VOC oxidation was studied.
• Wet air was more effective than dry air to remove coke and chlorine.
• Regeneration by wet air was effective for catalyst deactivated by DCE oxidation.
• Regeneration by wet air was ineffective for catalyst deactivated by TCE oxidation.

The objective of this work was to evaluate the feasibility of oxy-combustion treatments with the aim of restoring the catalytic activity and properties of H-BEA deactivated in the oxidation of chlorinated volatile organic compounds (Cl-VOCs), namely 1,2-dichloroethane (DCA) and trichloroethylene (TCE). The efficiency of regeneration treatments was analyzed by submitting the fresh H-BEA to cycles of reaction–regeneration–reaction. Conversion of Cl-VOCs was monitored with time on stream, and acidity, coke content and chlorine content on the catalyst surface were characterized before each step of the cycle. It was found that wet air was more effective than dry air to regenerate catalyst activity, especially at higher temperatures (500 °C), since it aided both coke removal and chlorine removal. The strong acidity and then the activity of H-BEA deactivated in the oxidation of DCA was fully recovered over and over again, since deactivation was mainly associated to coking, but not in the samples deactivated in the oxidation of TCE (more associated to chlorine attack).

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