| Popis: |
Adsorption tests were carried out in static mode, on natural phosphate samples both in a raw state and after processing. Various techniques of analyses were used (i) to characterize the material adsorbing on the granulo-chemical and thermo-mineralogical levels, (ii) to evaluate the performances of the process of adsorption used in relation to the existing mineralogical species, in phosphatic and gangueelements, (iii) to evaluate incubation condition in ions PO43-, carboxylate grouping and steric obstruction effect on lateral chains of adsorbates. This effect is significantly affected by the compositionof the incubation medium. Thus, the fractions low in phosphate ions appeared definitely more effective. The adsorption isotherms highlight a good correlation between experimental points and values predicted by Temkin model, confirming the influence of interactive effects on the used adsorbates. Study of the mechanisms of adsorption and the transfer mode of matter was carried out using the linear shape of the isotherm models, their respective correlation coefficients, the speed constants and the diffusion coefficients for the kinetic models based on reaction and diffusion. |
