No abstract

Textile industrial wastewaters have significant quantities of dyes. Adsorption processes using industrials rejects may help in the treatment of these effluents. In this context, uptake of Reactive Blue 5G dye by babassu coconut shell activated carbon was studied with upstream flow fixed-bed experiments. First, the minimum flow rate that minimizes the diffusion effects of 4 mL/min was chosen within the range investigated (2-10 mL/min). Then, the breakthrough curves were obtained for this flow rate for different initial dye concentrations (13.15-102.0 mg/L) and temperature of 30 °C. The mass retained until bed saturation in each experiment was used to obtain the dynamic isotherms, which showed a favorable dye uptake behavior with a maximum adsorption capacity of 12.9 mg.g -1 . The irreversible model fitted the experimental data well when compared to Langmuir and Freundlich models. A LDF model simulated the experimental breakthrough curves, and the bed axial dispersion and mass transfer coefficients were estimated.

RESUMO. Neste trabalho foi utilizada a metodologia de curvas generalizadas de secagem no estudo da cinética de secagem de papel reciclado obtido de forma artesanal com ar ambiente em convecção forçada, de forma a reunir, em curvas únicas, os dados de cinética de secagem obtidos em diferentes condições operacionais, reduzindo a quantidade de informação a ser manuseada. O módulo experimental utilizado consiste em uma caixa metálica por onde ar aquecido, com temperatura e velocidade pré-ajustadas, é canalizado por ambos os lados da amostra de papel artesanal, suspensa verticalmente sobre a corrente. O comportamento das curvas de secagem e de taxa de secagem obtidas para diferentes espessuras do material e diferentes temperaturas e velocidades do ar de secagem foi analisado a partir das abordagens de curvas de secagem generalizadas e taxas normalizadas de secagem, respectivamente. Em seguida, discutiu-se a possibilidade de ajuste de correlações da literatura às curvas generalizadas resultantes.Palavras-chave: curvas generalizadas, secagem convectiva, papel artesanal.ABSTRACT. Generalized drying curves in analysis of drying kinetic of kraft paper with environmental air in forced convection. The drying of kraft paper at forced air conditions is provided and the influence of the drying air operational conditions on the process behavior is analyzed through the generalized drying curves proposal. The experimental apparatus consists of a metallic box where hot air was canalized over both surfaces of the paper sample. The influence of the samples thickness and the drying air temperatures and velocities in the drying curves and drying rate curves behavior is studied through the methodology of generalized drying curves and normalized drying rate curves, respectively. Finally, the possibility of fitting these curves is discussed.

The chemical identification of Cannabis is commonly carried out using the Duquenois-Levine (DL) colorimetric test. On the other hand, its active substances called cannabinoids are differentiated by thin-layer chromatography (TLC). This work aims to optimize parameters of these two chemical tests using different samples of Cannabis in natura and previously heated (decarboxylated), as well as their isolated bioactive and possible false positives. The efficiency of the DL test without using ether and Highlights• Alternative to the colorimetric test of Duquenois-Levine using less toxic reagents.

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