Phosphate removal from aqueous solutions by using natural Jordanian zeolitic tuff
In this study, a naturally occurring zeolitic tuff located in Jordan was investigated as a potential
adsorbent for phosphate removal from aqueous solution. Adsorption kinetics and
thermodynamics of phosphate adsorption under different temperatures were studied. The
pseudo-second-order kinetic model adequately fitted the collected experimental data under
different initial ion concentrations. The Langmuir model is found to be successfully fitting the
experimental data. Thermodynamic parameters such as Gibbs?s free energy change, standard
enthalpy change, and entropy change were evaluated and the results indicated that the sorption
process is spontaneous, exothermic with small degree of randomness during the sorption process.