The Removal Efficiency of Remazol Black B (RBB) Textile Dyes by Chitosan Adsorbent from Aqueous Solutions

In recent years, wastewater textile treatment is of special importance due to the potential toxicity,cancer activity, and mutagens. The purpose of this study was evaluation of the removal of Remazol Black B (RBB) dyes from aqueous solution by chitosan.
This laboratory study carried out on synthetic wastewater to assess the effect of factors such as pH (4- 10), contact time (2-186 min), adsorbent dosage (0.25- 1 g/L) and dye concentration (30- 60 mg/L) on the removal of RBB Finally, Excel 2007 and ISOFIT (ISOtherm FItting Tool) software were used to analyze data and adsorption isotherm data, respectively.
The results showed that dye removal efficiency decreased with increasing pH, so that the maximum amount of dye removal (83%) was obtained in pH=4. Increasing the contact time of 2 to 66 minutes, dye removal efficiency with initial concentration 30 mg/L from 43% to 85% increases and then reaches an approximate constant value. Our results showed that by increasing the adsorbent dosage, removal efficiency increases and by increasing concentration dye, removal efficiency decreases. Adsorption isotherm data showed that the results of this study match better with GLF (Generalized Langmuir-Freundlich) model.
According to the results, chitosan can be used as an effective adsorbent for the removal of RBB dye in the textile industry wastewater or water contaminated with the dye.