Removal of heavy metals from water with natural adsorbent zeolite (Bi̇gadi̇ç/Balikesi̇r)

In this study, three different heavy metals (Cr3,6+, Ni2+, Cu2+) removal of the prepared the aquatic environment with natural zeolite adsorbent were studied. As an absorbent zeolite that taken from Balıkesir/Bigadiç was used. In addition adsorption isotherms and the work of thermodynamics, adsorption processes influencing mixing time, variation of the quantity of adsorbents, adsorbent particle size, stirring speed, pH changes, such as ambient temperature factors were investigated in detail for each heavy metal. Correlation coefficients were calculated by obtaining Freundlich and Langmuir adsorption isotherms for each heavy metal. Adsorption kinetics and thermodynamics were determined from pseudo first order, second order, ΔG0, ΔH0, ΔS0 equations and ion exchange capacity. According to experimental results the most appropriate adsorption isotherm Freundlich isotherm model were determined to be more appropriate of all metals was observed pseudo 2nd degree equation. Qe and KF values were calculated to be 1,89 and 3,11 for Cr+3, 1,16 and 2,66 for Cu, 3,00 and 4,29 for Ni. The values of ΔG0 for Cr+3 in 293, 298, 303 ºK temperatures were calculated to be -1,98 kJ/mol, -2,83 kJ/mol, -4,41 kJ/mol, respectively. ΔH0 and ΔS0 values were calculated to be, 5,79 kJ/mol and 0,02 kJ/mol.K, respectively. The values of ΔG0 for Cu in 293, 298, 303 ºK temperatures were calculated to be -5,56 kJ/mol, -5,45 kJ/mol, 303 -5,43 kJ/mol, respectively. ΔH0 and ΔS0 values were calculated to be, -9,56 kJ/mol ve -0,02 kJ/mol.K, respectively. The values of ΔG0 for Ni in 293, 298, 303 ºK temperatures were calculated to be 1,81 kJ/mol, 0,76 kJ/mol, 0,19 kJ/mol, respectively. ΔH0 and ΔS0 values were calculated to be, 4,00 kJ/mol and 0,01 kJ/mol.K, respectively. Optimum adsorbent particle size 120 mesh for Cr+3 and Ni, 230 mesh for Ni, optimum stirring speed 250 rev/min for Cr+3, 200 rev/min for Cu and 50 rev/min for Ni, optimum pH values 5 for each heavy metal were calculated.