Study of the effect of the concentration of hydrotalcite in the recovery of colorants in textile wastewater

Abstract

[EN] The absorption capacity of calcined hydrotalcite at different concentrations in a solution of 0.05 g . L-1 of 4 different dyes has been compared; Direct Blue 199, Direct Red 23, Direct Blue 71 and Reactive Yellow. For this, the Lambert-Beer lines of each dye have been previously made. Two different concentrations of clay, 5 and 10 g . L-1, have been worked. Then the dye has been introduced into the clay by stirring for 24 hours in 100 ml of solution of each dye, to later filter it and allow to dry. In all cases, the absorption of the dye by the nanoclay has been almost absolute, leaving the initial solution very clean, which are excellent results from the point of view of cleaning wastewater. However, when obtaining very similar results when scaling it to an industrial production, it would be more optimal to use the lowest concentration in order to reduce costs. Finally, a color measurement was made using a Jasco V-670 spectrophotometer, double beam spectrophotometer between 190- 2700 nm and color differences are calculated and represented in a color chart. Again, no large differences are observed and reinforce the idea of using a low concentration.