Adsorption of Pb(II) from aqueous medium by schist ashes containing bitumen

Adherence of the gases that collide solid or liquıd surfaces or that of dissolvedsubstances is called adsorption.Adsorption is the one of efficient methods widely used forremoval of environmental pollution.However,cost is an important parameter in this prosessand use of low cost local resources to process harmful wastes is also important for develop-ment of environmental biotechnology.In the present study, very low cost Şırnak asphaltite coal ash was used as adsorbentand Pb(II) ions were removed from aqueous solution.In the adsorption studies,influenceofinitial concentration, adsorbent dosage, pH,equilibrium contact time and temperature wasinvestigated.A certain amount of adsorbent was mixed with a certain amount of metal ion solutionInitial concentration of which was known and reduction in equilibrium concentration as afunction of time was measured. Thus kinetic data were obtained and equilibrium time wasdetermined. Then these kinetic data were evaluated pseudo-first order and pseudo-secondorder rate models and so adsorption cost were established . Furthermore,activation energywas calculated by using rate constants in different temperatures.A certain amount of adsorbent and a series of solution in different concentrations wereagitated for the determin equilibrium time. Adsorption isotherms were obtain by plottingamount of the metal ion adsorbed on unit amount of adsorbent versus equilibrium constant.Then adsorption isotherm data were assessed Freundlich and Langmuir isotherm models.Thermodynamic parameters such as adsorption isotherm constants, changes in free energy(?G), enthalpy (?H) and entropy (?S) were calculate by the aid of these data.