Desenvolvimento de um simulador em linguagem Visual Basic for Applications para processos fotocatalíticos de transformação

Abstract

The present work aims to apply the Excel® spreadsheet tool in the development of a simulator applied to photocatalytic reactors. Toluene degradation was selected as the study case for implementing the simulator. The Visual Basic for Applications (VBA) programming language was applied for numerical methods as well as for generating of graphics and an efficient interface. It is also worth highlighting the availability of Microsoft® programs, making the tool more accessible in solving process system engineering problems. A model system from the literature describing the kinetics of a toluene photocatalytic oxidation reaction was simulated. The contaminant concentration profile (toluene) is obtained as a function of position in the reactor and also based on input operational data, meaning that system and reaction information can be freely altered. This allowed the study of different reactor dimensions, flow rates, initial concentrations, reaction rates, and catalyst characterization parameters. The reactional system was designed so that the catalyst present in the annular fixed bed receives radiation properly. The simulation was performed considering the model as onedimensional and in a steady state. The results obtained were satisfactory for determining the toluene degradation velocity profile as well as the photoreactor sizing values. For the operational conditions of the process, simulations were conducted by varying the dimensions of the photoreactor, both length and radius, as well as the radiation intensity. The results demonstrated that the developed tool allows the simulation and analysis of the toluene photocatalytic degradation process as a function of the main involved variables and parameters.