Aplicação das técnicas de processamento digital de imagens na caracterização de carvão ativado da biomassa do coco babaçu

Abstract

Activated carbon (AC) is a form of pure carbon of great porosity that adsorbs molecules or ions in a fluid medium. In order to characterize the porosity in micro, meso and Macroporos, using scanning electron micrographs (SEM) of the CA, the open source software (free software), ImageJ, was applied using digital image processing techniques (PDI). The CA used in the work was produced from the biomass of babassu coconut processed in a microwave oven at three different temperatures: 700, 750 and 800 ° C. The developed methodology uses defined pre- processing filters based on tests and selected to reduce noise, improve the image, preparing it to be processed and analyzed by the developed system. The results from the PDI were related to the results from the conventional characterization method, BET (Brunauer, Emmett and Teller). The paper presents the theoretical basis of the computational techniques that were used in the development of the PDI algorithm. The analyzes carried out on the samples highlighted the characteristics and details that each sample possesses in the different temperatures that were necessary to the development of two processing flows in order to apply the PDI techniques that would meet the needs and nuances that each micrography requires. Due to the technological limitations of resolution of the SEM, the methodology developed used a relation between the surface in micrometer with its internal porosity in nanometers, it was observed that the analyzes in samples of 700ºC with the magnification of 1800 times obtained a great value with a deviation satisfactory standard and much lower than the other samples analyzed compared to the results of the BET analysis.