The nanoparticles of TiO2 which are synthesized by hydrothermal method were studied. The obtained TiO2 powder was characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). In this study, the TiO2 nanoparticle was used for the removal of Cu(II) ion and Malachite green from aqueous solution. In the adsorption experiments the batch method was performed. The effect of contact time, pH, amount of adsorbent and concentration of adsorbate were optimized. In the study to find the nature of adsorption isotherm form, the Langmuir, Freundlich, Temkin and D-R isotherms were used to fit the experimental results. Correlation coefficients were determined by analyzing each isotherm. The results indicate that the Freundlich isotherm for Cu(ΙΙ) ion and Malachite green dye showed better correlation with the experimental data than the other isotherms.
In the kinetic studies, first order, pseudo-first-order, second order and pseudo-second-order were examined for the collected experimental data. The kinetic data of the adsorbtions of Cu(ΙΙ) and Malachite green dye on Titania, shows better correlation with the pseudo-second-order model.
The thermodynamic parameters such as standard enthalpy change (ΔH°), standard entropy change (ΔS°) and standard free energy change (ΔG°) were also evaluated. These parameters indicated that the adsorption of Cu(ΙΙ) ion and Malachite green dye is endothermic process and physisorption.

The nanoparticles of Al₂O₃ which are synthesized by hydrothermal method were studied. The obtained Al₂O₃ powder was characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). In this study, the Al₂O₃ nanoparticle was used for the removal of Cd(II) ion and Safranin from aqueous solution. In the adsorption experiments the batch method was performed. The effect of contact time, pH, amount of adsorbent and concentration of adsorbate were optimized. In the study to find the nature of adsorption isotherm form, the Langmuir, Freundlich, Temkin and D-R isotherms were used to fit the experimental results. Correlation coefficients were determined by analyzing each isotherm. The results indicate that the D-R isotherm for Cd(ΙΙ) ion and the Langmuir isotherm for Safranin dye showed better correlation with the experimental data than the other isotherms. The maximum adsorption capacity for Cd(ΙΙ) and Safranin ions were 26.316 and 33.223 mg per g of adsorbent respectively.
In the kinetic studies, first order, pseudo-first-order, second order and pseudo-second-order were examined for the collected experimental data. The kinetic data of the adsorbtions of Cd(ΙΙ) and Safranin dye on Alumina, shows better correlation with the pseudo-second-order model.
The thermodynamic parameters such as standard enthalpy change (ΔH°), standard entropy change (ΔS°) and standard free energy change (ΔG°) were also evaluated. These parameters indicated that the adsorption of Cd(ΙΙ) ion is endothermic process and physisorption, and for Safranin dye is exothermic process and physisorption, and in both case the adsorption process are spontaneous.
 

The aim of the present work is to investigate the ability of crushed particles of sheep wool to remove Pb (ΙΙ) and Safranine ions from aqueous solution. In this work bath adsorption experiments were carried out and the effects of the pH solution, temperature, metal ion concentrations, adsorbent dosages, and contact time were studied. The experimental data were analyzed using the Langmuir, Freundlich, Temkin and D-R isotherms. Correlation coefficients were determined by analyzing each isotherm. The results indicate that the Freundlich isotherm for Pb (ΙΙ) ion and the Langmuir isotherm for Safranine dye showed better correlation with the experimental data than the other isotherms. The maximum adsorption capacity for Pb (ΙΙ) and Safranine ions were 12.787 and 4.653 mg per g of adsorbent.
In the kinetic studies, first order, pseudo-first-order, second order and pseudo-second-order were examined.The kinetic data of Pb (ΙΙ) and Safranine dye could be better described by the pseudo second-order model.
The thermodynamic parameters such as standard enthalpy change (ΔH°), standard entropy change (ΔS°) and standard free energy change (ΔG°)were also evaluated. These parameters indicated that the adsorption of Pb (ΙΙ) and Safranine ions were exothermic processes, and the adsorption process was associated by decreasing the entropy.
 

 In the first part of this research, The nanoparticle which were synthesized by sol-gel method was used to the removal of the Cd(II) ions by one variable at a time method. The Co3O4 nanoparticle were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray iffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). In order to obtain maximum removal percentage,the effects of pH, volume of buffer, amount of adsorbent, contact time, volume of solution and temperature were investigated. The Langmuir, Freundlich, Temkin and D-R isotherms used to fit the experimental results. The results showed that Langmuir isotherm of Cd(II) is the best fit with the experimental results and also illustrated that adsorbent capacity is 44.44 . Thermodynamic parameters such as standard enthalpy ( ), standard entropy ( ) and standard Gibbs free energy ( ) were calculated. In the kinetic studies, four kinetic models include first-order, pseudo-first order, second order and pseudo-second order are studied. The results showed that the pseudo-second-order kinetic model for adsorbed Cd(II) over the nanoparticles has the best agreement with experimental data.

In the second part by using the Taquchi method analyzes, the optimum conditions for removal of Cd(II) from aqueous solution by Co3O4 nanoparticle which is prepared using the sol-gel method. The controllable factors used in this study consisted of the following: pH of the solution, adsorption temperature, amount of adsorbent and contact time. The experiments were designed according to Taguchi’s ( ) orthogonal array to optimize experimental runs. Analysis of variance was applied to determine the significant parameters that effect on adsorption

The Aim of this theses is to investigate the ability of nanoparticle to remove Cd(II) and Zn(II) from aqueous solution.

Cr2O3 nanoparticles were prepared by employing, sol-gel technique. The synthesized solid sorbent was characterized by Fourier transform Infrared (FTIR) spectrometry, X-ray Diffraction (XRD)and Transmission Electron Microscopy(TEM). In the present study, the application for the removal of Co(II) and Cd(II) ions from aqueous solution by using Cr2O3 nanoparticles. For this aim, batch adsorption experiments were carried out. The effects of pH solution, temperature, metal ion concentrations, adsorbent dosages, and contact time were studied. The experimental data were analyzed using the Langmuir, Freundlich, Temkin and D_R isotherm. Correlation coefficients were determined by analyzing each isotherm. The results indicated that the Freundlich isotherm for Co(II) and Cd(II) ions showed better correlation with the experimental data than the other isotherms. The thermodynamic parameters such as standard enthalpy change, standard entropy change and standard free energy change were also evaluated. The adsorption for Co(II0 and Cd(II) ions is physical in nature and exothermic.