| Chlorofluorocarbons (CFCs) have been brought about many destroys on humanity health, ecological and globosity environment because CFCs are green house gases. The harmless and resources disposition of CFCs has been a hot topic in recent years, and it is significantly important to develop low concentration CFCs decomposition technique before being liberated into the atmosphere. Low concentration CFCs, dichlorodifluorocarbons (CFC-12), as an example, were catalytic hydrolyzed over solid acid and alkali catalysts, which were prepared by metal oxide supported ZrO2. Factors of catalyst preparation, techniques of catalytic hydrolysis, mechanism, thermodynamics and dynamics were emphasis studied in this paper.From the optimization experimentation, the catalysts prepared by optimum conditions of solid acid MoO3/ZrO2 are, one times superaturation dipping, the concentration of (NH4)6Mo7O24·4H2O 0.5 mol.L-1, the ratio of liquid to solid 1.5, the dipping temperature 80℃and 4 hours, the quality percent of ZrO2 20-40%, and the calcination temperature 450℃. Solid base Na2O/ZrO2 were, Zr:Na=1:0.35, the calcination temperature 600℃. Solid base CaO/ZrO2 were, Zr:Ca=1:0.35, the calcination temperature 650℃.Catalytic hydrolyzed of low concentration CFC-12 was investigated over solid acid-base catalysts. The optimum hydrolytic conditions of solid acid MoO3/ZrO2 were, the hydrolytic temperature 250℃, the composition of reaction gases (mol%),1.0 CFC-12,40.0 H2O(g),10.0 O2, others N2, high stability and selectivity, and regenerated by heat or dipping. The optimum hydrolytic conditions of solid base Na2O/ZrO2 and CaO/ZrO2 were, the hydrolytic temperature 260℃, the composition of reaction gases 1.0 CFC-12,50.0 H2O(g),8.0 O2, others N2, the space velocity 1000 h-1, and the humidity in air brought on catalyst poisoning and regenerated by heat. Catalytic hydrolysis mechanisms for low concentration CFC-12 were studied. Catalysts were characterized by BET, TEM, TPD, XRD and FT-IR. (1) Solid acid MoO3/ZrO2. Distribution of pore size was narrowly range from 1.5 to 6.0 nm, mainly in and the main active pore size was 3.90 nm. Crystalline size increased with the calcination temperature rise and it was in the main form of crystalline phase. Calcination temperature affected acid species of MoO3/ZrO2, which has corresponded weak acid sites, and middle intensity and strong acid sites increased with the calcination temperature. The weak, middle intensity and strong acid sites jointly catalyzed the CFC-12 hydrolysis. MoO3 and ZrO2 framework in catalysts formed strong acids in the form of strong interaction. (2) Solid base Na2O/ZrO2 and CaO/ZrO2.The total pore volume and average pore size were raised with calcination temperature rising, and the specific area was raised and declined with calcination temperature. Mesoporous complex substance was mutual chimeras by ZrO2 crystalline grain, and Na2O or CaO nanometer grain, which has bore diameter 15-35 nm, high specific area and activation. Solid base Na2O/ZrO2 had desorption peaks in the temperature range from 75 to 425℃and solid alkali CaO/ZrO2 in the temperature range from 425 to 625℃. These peaks drift to high temperature with the calcination temperature rise. Solid alkali Na2O/ZrO2 (calcinated at 600℃) had much t-ZrO2 and m-ZrO2, however CaO/ZrO2 (calcinated at 650℃) had much t-ZrO2 and little m-ZrO2. Absorption peaks of solid alkalis decreased with the calcination time prolonged and temperature rise, and the m-ZrO2 was the main active ingredient. The formation model of acid-base center and the reaction mechanism model of low concentration CFC-12 catalytic hydrolysis over acid-base catalysts were brought forward.Adsorption isotherm of CFC-12 was imitated by Freundich isothermal equation, and adsorption isochore was imitated by Clausius-Clapeyron equation. The adsorption heat-(?)HAM of CFC-12 over solid acid was calculated as 56.30-73.22 kJ.mol-1, belong to chemical adsorption. The adsorption heat of CFC-12 over solid base Na2O/ZrO2 and CaO/ZrO2 were calculated. The equilibrium constant and the activation energy were calculated under reaction temperature 260℃.The activation energy, reaction rate equation and reaction order were calculated from the adsorption capacity curve of low concentration CFC-12 by Bangham adsorption rate formula and Arrhenius equation. The reaction order declined and the reaction rate constant K has gone up with reaction temperature rising, the activation energy 123.12 kJ.mol-1 over solid acid MoO3/ZrO2. The activation energy, reaction rate equation and reaction order were calculated of CFC-12 over solid base Na2O/ZrO2. The reaction order declined and the reaction rate constant K has gone up with reaction temperature rising, the activation energy 51.18 kJ.mol-1 in the primary stage. The reaction order declined and the reaction rate constant K has gone up with reaction temperature and declined with the reaction time, the activation energy reached to 312.74 kJ.mol-1 in later stage.
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