Adsorção de azul de metileno em solução aquosa com pó de serragem de Erisma uncinatum Warm

Abstract

The quantity and diversity of dyes present in industrial textile effluents discharged into the water bodies generate negative impacts on the environment. Therefore, it is necessary to carry out treatments in order to minimize the effects. One of the simplest and least expensive forms is the adsorption process. This paperwork aims to evaluate the removal of a methylene blue dye at a concentration of 0.025 g/L by adsorption process with sawdust powder as an alternative adsorbent to activated carbon. Initially, the specific density, apparent density, pH, moisture content and particle size tests were used to characterize the sawdust powder. A rotational central composite design was used as a way of planning experiments in order to analyze the impact of temperature and pH in the adsorption process. The temperature varied from 30 °C, 34 °C, 45 °C, 56 °C to 60 °C and pH from 3, 4, 7, 10 to 11. An acid characterization was obtained from the sawdust powder (pH 5.59 (0.01)) and the moisture content was 24%. For all assays, dye removal was above 80% on average. The best efficiency (87.03%) was obtained at a temperature of 45 ° C and pH 11 with 3 g of sawdust powder. And the best dye removal result (88.56%) was observed for the time of 5 minutes at 45 ° C and pH 11. For all the tests performed, the experimental data were better adjusted to the pseudo-second order model, which describes a chemical adsorption. According to the statistics, pH and temperature did not significantly influence the adsorption. Therefore, the conclusion is that the use of sawdust powder for the removal of methylene blue dye is efficient and satisfactory.