Preparation and characterization of renewable biopolymer based alginate adsorbent for removing of crystal violet dye from water

Purifying water resources with sustainable technologies is essential for the future of humanity. Crystal violet is one of the most polluting dyes and is harmful to aquatic ecosystems. Therefore, its removal from water is very important for environmental health. In this study, the removal of crystal violet dye from water was investigated using a carbon nanotube-loaded alginate adsorbent, which is environmentally friendly and does not generate unwanted byproducts. Modified alginate attracts attention as a biocompatible, sustainable, environmentally friendly and renewable adsorbent. Functionalized multi-walled carbon nanotube-loaded alginate adsorbent beads were developed for the removal of crystal violet from water. Adsorbents were characterized by FTIR, TGA, and SEM analyses. The Design Expert 12 student version was used for the statistical analysis. Three variables adsorbent dosage, solution concentration, and time, were investigated using the Response Surface Method (Box-Behnken design model) to determine the response (crystal violet removal %). The experimental data were found to be compatible with the quadratic model. According to the ANOVA, the most effective variable was the removal timeby adsorption. An adsorption capacity of 32.05 mg/g was obtained from the adsorbents for the adsorption of crystal violet from water. It was observed that the experimental data were compatible with the Langmuir isotherm and the pseudo-second-order kinetic model. It was concluded that the prepared composite adsorbents are suitable for the removal of crystal violet from water.