Control-oriented modeling of diesel oxidation catalyst

Diesel oxidation catalyst outlet temperature control is crucial for heat management to realize diesel particulate filter active regenerative control. In order to control the temperature of the active regeneration process in the filter, the temperature response process of the semi-physical oxidation catalyst model structure is proposed as a multi-stage inertia plus delay, and the equivalent inlet temperature step of the fuel oxidation reaction of the exhaust pipe. Combined with the test test, the control oriented oxidation catalyst model is established.A control-oriented oxidation catalyst model was constructed. By analysed the oxidation catalyst working process, the main chemical reactions, heat and mass transfer processes occurring inside the carrier were analyzed. Three-dimensional CFD model and one-dimensional chemical reaction kinetics model were established respectively. The radial and axial temperature distribution of the carrier was analyzed by model simulation. Based on the analysis of the system characteristics, the multi-step inertia plus delay semi-physical model structure was proposed. Combined with the test, the control oriented oxidation catalyst model is established. Select the appropriate working conditions to identify and verify the model parameters. The results show that the third order model can well indicate the temperature response characteristics of the oxidation catalyst outlet temperature. Considering the complexity of the system, the first-order and third-order model are selected as the basis of the control system design.

Electrochemical Reaction and Dissociation of Glycerol on PdAu Surface Catalyst

Direct Glycerol Fuel Cell is one of the alternative energy that can produce electricity without burning. The production of electricity without combustion can reduce the use of fossil fuel as well as reduce environmental pollution. A new catalyst of PdAu has been synthesized in this study to increase the activity of the glycerol oxidation reaction. Morphologies analysis was performed on CNF-supported synthesized PdAu. FESEM and TEM image show the PdAu supported on the CNF surface. Both PdAu and CNF has a diameter size of 4-6 nm and 80-130 nm, respectively. In CV analysis, PdAu/CNF has produced an oxidation peak and current density at -0.9 V vs. SCE and 70 mA/cm2, respectively. Each mechanism of glycerol dissociation step during glycerol oxidation, different atomic active sites are required in PdAu. For example, for glycerol adsorption, Au atom as an active site while for *C3H7O3 requires Pd atom and Au atom as the active site. The Au catalyst model shows better adsorption as Au/CNF has a slightly more negative oxidation peak than PdAu. Nevertheless, the Au catalyst showed less durability compared to PdAu.

Complex Modelling and Design of Catalytic Reactors Using Multiscale Approach—Part 2: Catalytic Reactions Modelling with Cellular Automata Approach

The presented work is devoted to reactions of obtaining 4,4’-Diaminodiphenylmethane (MDA) in the presence of a catalyst model. The work describes the importance of studying the MDA obtaining process and the possibility of the cellular automata (CA) approach in the modelling of chemical reactions. The work suggests a CA-model that makes it possible to predict the kinetic curves of the studied MDA-obtaining reaction. The developed model was used to carry out computational experiments under the following different conditions—aniline:formaldehyde:catalyst ratios, stirrer speed, and reaction temperature. The results of computational experiments were compared with the corresponding experimental data. The suggested model was shown to be suitable for predicting MDA-obtaining reaction kinetics. The proposed CA model can be used with the CFD model, suggested in Part 1, allowing the implementation of complex multiscale modeling of a flow catalytic reactor from the molecule level to the level of the entire apparatus.