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The sorption of the uranium(Ⅵ) ions from aqueous solutions by diethylethanolammonium organovolcanics (Kula-TURKEY) was investigated under different experimental conditions.DEEA was used to modify the surface of basaltic volcanics.The characteristic of basaltic volcanic was analyzed by XRF,SEM-EDS,FTIR,and XRD.The BET surface areas of unmodified volcanics and DEEA-modified volcanics were found as 2.265 and 3.689 m2/g,respectively.The volcanic samples were treated by using different concentrations of DEEA.The adsorption of U(Ⅵ) on natural and modified volcanics was examined as a function of the contact time,initial pH of the solution,initial U(Ⅵ) concentration,and temperature.Langmuir,Freundlich,and D-R adsorption isotherms were used to describe the adsorption.While examining the adsorption percentage and distribution coefficient,these values for unmodified volcanics were found to be 25％ ± 0.76 and 10.08 mL/g,while the values for the DEEA-modified volcanics were 88％ ± 1.04 and 220 mL/g,respectively.The pseudo-first-order and pseudo-secondorder kinetic models were used to describe the kinetic data.In this study,it can be seen that the adsorption process is suitable for the pseudo-second-order kinetic model.Various thermodynamic parameters (ΔG°,ΔH°,and ΔS°) were calculated with the thermodynamic distribution coefficients obtained at different temperatures.The sorption process was a chemical adsorption process.The results indicated that the processes are spontaneous and endothermic.