Ionic gelation synthesis, characterization and adsorption studies of cross-linked chitosan-tripolyphosphate (CS-TPP) nanoparticles for removal of As (V) ions from aqueous solution: kinetic and isotherm studies

The CS-TPP nanoparticles were synthesized and their efficiency for removal of arsenic (V) ions at the optimum conditions was investigated. The optimum conditions for CS-TPP nanoparticles were obtained with the mass ratio of tripolyphosphate to chitosan of 1: 2 and pH = 5.0. The experimental data for the adsorption of As (V) ions followed the Freundlich adsorption isotherm and the maximum adsorption capacity was 77 mg/g at pH = 6.0. All isotherm experiments were performed at room temperature (25 °C). The crosslinking of sodium tripolyphosphate with the chitosan led to a decrease in crystallinity of the formed particles which then resulted in an improvement in metal ion sorption properties.