Experimental And Modeling Study Of Reverse Flow Reactor For Catalytic Combustion Of Acrylinotrile Absorber Off Gas

Acrylinotrile is one of the most important raw materials, and it has been widely used for synthetic materials, such as plastic, rubber and fiber. The off gas from the absorber of industrial plant contains carbon monoxide, propylene, propane, which will seriously pollute the environment if emitted freely. Thus, this study focused on the catalytic combustion of the absorber off gas using a reverse flow reactor. The intrinsic kinetics of catalytic combustion of the off gas were investigated, and the catalytic combustion in a reverse flow reactor with inter-heat exchanger was conducted, then modeling and simulation of the reverse flow reactor was used to predict the operating performance.Firstly, the catalytic combustion of the individual component and the mixtures of carbon monoxide, propylene and propane were investigated by using an integral microreactor under the condition without diffusion limitation. The adsorption properties of the reactants were probed by the TPD technique to distinguish the probable reaction mechanism. The Eley-Rideal kinetic models were selected to fit the experimental data of individual component conversions, and the parameters of the models were estimated through the partial least-square (PLS) method and simplex search optimization. The calculated conversion values of every component are in good agreement with the experimental data. Also, it is found that the conversions predicted by the individual component kinetic models are consistent with the experimental results of the mixture catalytic combustion.Secondly, the catalytic combustion of acrylinotrile off gas was systematically investigated in a reverse flow reactor with inter-heat exchanger. The influences of cycle period, space velocity, and feed concentration on operation performance of reactor with heat extraction were observed. The experimental results showed that, for the reverse flow reactor, cycle period, space velocity and feed concentration were three important operating parameters that obviously affect the axial asymmetry temperature profiles of the reactor. At the same time, the extinction and run-away behavior of reactor were observed to find the reasonable range of the operation parameters.Thirdly, a one-dimensional heterogeneous differential mathematic model describing the reverse flow reactor was derived carefully from mass and heat balance. The verification of this model was conducted by comparison of the simulated results with experimental data. The comparison showed that the mathematic model of reactor was reasonable, adaptable and robust. Then the model was employed to simulate the performance of the reactor with different operating and design parameters, and predict the range of suitable operating and design parameters.