RESUMO O corante azul de metileno, amplamente utilizado na indústria têxtil, é capaz de causar sérios danos, caso despejado nos corpos hídricos sem o devido tratamento. O objetivo deste trabalho foi estudar a eficiência do uso de bambu, in natura e carvão vegetal, como bioadsorvente na remoção do corante azul de metileno. Para isso, o bambu in natura e o bambu ativado termicamente foram produzidos e caracterizados por meio de análises de área superficial específica, termogravimétricas, microscopia eletrônica de varredura e espectroscopia no infravermelho. Ensaios de adsorção, em batelada, foram realizados com os bioadsorventes produzidos, utilizando planejamento experimental, do tipo fatorial 2³ e repetição do ponto central. Foram obtidas as condições do processo de adsorção para o bambu in natura, com 16 g/L de concentração de adsorvente, 50 mg/L de concentração de corante e pH =10, alcançando uma eficiência de remoção de 98,1%. As mesmas condições foram usadas com o bambu carvão, obtendo-se uma eficiência de remoção do corante de 92,2%. A diferença observada na porcentagem de remoção do corante deve-se às características de cada bioadsorvente. Os resultados demonstraram que o uso do bambu como bioadsorvente pode ser uma alternativa eficiente e sustentável para o tratamento de efluente com corantes pelo processo de adsorção.

ABSTRACT The methylene blue dye, widely used in the textile industry, is capable of causing serious damage if dumped into water bodies without proper treatment. The objective of this work was to study the efficiency of using bamboo, in natura and charcoal, as bioadsorbents in the removal of methylene blue dye. For this, fresh bamboo and thermally activated bamboo were produced and characterized by specific surface area, thermogravimetric, scanning electron microscopy and infrared spectroscopy. Batch adsorption tests were carried out with the bioadsorbents produced, using an experimental design, of the 23 factorial type and repetition of the central point. The conditions of the adsorption process for bamboo in natura were obtained, with 16 g/L of adsorbent concentration, 50 mg/L of dye concentration and pH =10, achieving a removal efficiency of 98.1%. The same conditions were used with charcoal bamboo, obtaining a dye removal efficiency of 92.2%. The difference in dye removal percentage is due to the characteristics of each bioadsorbent. The results demonstrate that the use of bamboo as a bioadsorbent can be an efficient and sustainable alternative for the treatment of effluent with dyes through the adsorption process.

In the present work, the application of a didactic activity proposed for the teaching-learning of mass transfer initial concepts unit operations for students of Introduction to Chemical Engineering course of a public institution was evaluated. For this, the class was separated in four moments: brief introduction to the subject, pre-test application, experimental activity and post-test application. Also, a survey of students' satisfaction about the activity was conducted by e-mail and on a voluntary basis. The results obtained from the pre- and post-test were analyzed using Wilcoxon's nonparametric statistical test. This way, it could be verified that the proposed didactic methodology contributed positively in the teaching-learning process of these students.