Toluene Removal By A Sequential Adsorption-Thermal Catalytic Process On Ag/Hopcalite

Hopcalite supported Ag (wt.%: 0.5; 1; 2; 10)-containing materials were prepared by wet impregnation followed by calcination at 400 degrees C for adsorption-thermal catalytic oxidation of toluene. Based on breakthrough experiments, the duration of the adsorption step was set around 38 min to minimize toluene loss at the outlet of the reactor (<3 mol% of the amount of toluene adsorbed) allowing to determine a dynamic useful adsorption capacity for toluene. Thermal oxidation was performed in a He : O-2 (75 : 25) gaseous mixture from 20 degrees C to 250 degrees C (90 min) to assess the catalytic properties of the bifunctional materials throughout on-line monitoring of unreacted toluene and CO2 during the temperature programmed reaction. Hop-0.5 Ag exhibited the best performance with a CO2 yield of 98.9 %. Excellent redox properties and minimization of thermal effects were invoked to enhance total oxidation of toluene. Additionally, these bifunctional materials showed good stability under cycling conditions.