| Since the pollution of nitric oxides (NOx) in china has been more and more serious in recent years, it is necessary to take measures to control emission of NOx. In the dissertation, selective catalytic reduction (SCR) of NOx by ammonia was adopted and the choice of catalyst is the core of the technology. Take cordierite honeycomb as the substrate for its low-cost, high thermal stability, then load the washcoatγ-Al2O3 and active phase CuO, it can a form new honeycomb catalysts with higher denitrification activity in the 350-450℃.This paper prepared CuO/γ-Al2O3 catalyst in a cordierite support using an equivalent-volume incipient wetness impregnation method, the amount of y-Al2O3 loading was 5.0% and characterized using a variety of means to describe the catalysts.The denitrification performance of catalyst was tested in a fixed-bed reactor pre-sulfuration treatment. Experimental results showed that when the CuO loading capacity of 1.5%, the catalyst activity is the highest denitrification; when the particle diameter was 80-100 mesh, space velocity was 0.056 cm3·h-1·g-1, It can eliminate the internal and external diffusion under the conditions.In this work the intrinsic kinetics of SCR of NO with NH3 over CuO/γ-Al2O3/cordierite catalyst has been reached in a fixed-bed reactor in the absence of internal and external diffusions in the temperature range 320-420℃. The experimental results show that when the concentration of NH3 is higher than that of NO in feed, the SCR reaction rate can be quantified by a first-order expression with a pre-exponential factor of 3.39×108 cm3·g-1·s-1 and an activation energy of 94.0 kJ·mol-1. However, when NH3 is not enough, according to Eley-Rideal mechanism and Langmuir Hinshelwood Hougen Watson hypothesis, a kinetic model is derived with a pre-exponential factor of 2.94×109 cm3·g-1·s-1, an activation energy of 105.8 kJ·mol-1, heat of adsorption of 87.9 kJ·mol-1 and Aads= 9.244 cm3·mol-1. Adsorption equilibrium constant K is extremely small in magnitude, so the experimental data can also be fitted to the first-order model. The kinetic parameters fall within the range of previously determined experimental values for other catalysts without cordierite support. The experimental data are in good agreement with kinetic model predictions, indicating that the proposed kinetic model could be successfully used for detailed description of physico-chemical processes in SCR reactors. Furthermore, the mathematical model of monolithic honeycomb SCR reactor, in which the intrinsic kinetic model obtained in this work was incorporated, was established. The predicted results were compared with the experimental data to verify the reliability, and it was found that the mathematical model of monolithic honeycomb SCR reactor can be used for the reactor design and engineering scale-up.
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