Nanoclay and modified nanoclay as sorbents for anionic, cationic and nonionic dyes

The nanoclay, montmorillonite, and some modified nanoclays were used as sorbents for nonionic, anionic and cationic dyes. From the sorption differences among the different dye and clay structures, both chemical and morphological, the sorption forces that played important roles were identified. The nanoclay could easily have a sorption capacity of more than 600 mg sorbate per gram of sorbent at a liquor-to-sorbent ratio of 100 to 1. Furthermore, it could have a sorption of 90% at an initial dye concentration of 6 g/L, or 60% based on the weight of the sorbent, indicating an extremely high dye affinity. This study showed that with certain modifications the nanoclay, montmorillonite, could easily become an excellent sorbent for anionic, cationic and nonionic dyes.