Modelling the sorption of 63Ni to granitic materials: application of the component additive model
journal contributionposted on 27.06.2013, 11:24 by Fidelis Sameh Ebong, Nick Evans
The component additive modelling approach is based on summing the results from models already calibrated with pure mineral phases. The summation can occur as the sum of results for thermodynamic surface speciation models or as the sum of pseudo-thermodynamic models for adsorption on individual mineral phases. Static batch sorption experiments of 63Ni are with different granitic rocks and component minerals. XRD analyses have been used to calculate the percentage mineralogical composition of the granitic rocks. Sorption data has been modelled using non electrostatic correction models to obtain Rd for the granitic rocks and mineral. Rd values for the granitic rocks predicted from the component additive model have been compared to experimental values. Results showed that predicted Rd values for granite adamellite, biotite granite and rapakivi granite were identical to the experimentally determined values, whereas, for graphic granite and grey Granite, the predicted and experimentally determined Rd values were much different. The results also showed a greater contribution to the bulk Rd by feldspar while quartz showed the least contribution to the Rd.