Undoubtedly, one of the most important issues in the various industries is the pollutants removal from the environment. Adsorption as a separation method is one of the most outstanding methods in this field. Compounds based on natural or synthetic biodegradable polymers have considered as one of the most desirable adsorbents in the removal of pollutants from the contaminated water. Nowadays different methods have proposed to improve the absorption properties of these polymers. In this study, nanocomposites based on chitosan, poly (vinyl alcohol) or blend of chitosan and poly (vinyl alcohol) reinforced with calcium carbonate nanoparticles (CC NP) have been prepared by solution-casting method under ultrasonic irradiations. In this regard, small molecules such as ?-aminopropyl triethoxy silan and folic acid is used as coupling agent to improve the dispersion and better compatibility of with the organic polymer matrix. The modified CC and the prepared nanocomposites were detected by Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, surface electron scanning microscopy, transission electron microscopy and thermal gravimetric analysis. Adsorption ability of copper (II) ion and malachite green dye from aqueous solutions was studied by nanocomposite adsorbents in a bach system. During adsorption, the effect of different variables such as pH solution, adsorbent dose, contact time and initial concentration of solution was studied. The experimental data were analyzed using linear and nonlinear regression analysis with isotherm and kinetic and thermodynamic models. Several error functions were examined for the validity of each model. In addition, the bioactivity behaviours of these nanocomposites are investigated in the body's fluid simulation for formation hydroxyl apatite at controlled temperature and pH. The results showed that the apatite layer was deposited on the sample surface in simulated body fluid. The bioactivity potential of prepared nanocomposites was found to be better than the pure chitosan.
