Table 6.
Wet chemical analysis (concentrations in mg/L), chemical composition (concentrations in wt. %) and atom per formula unit (a.p.f.u.) calculation of the solid phases collected at the end of the anionic competition experiments. FApth indicates the theoretical values for fluorapatite. The general crystallochemical formula used for the apatite group minerals is M5(TO4)3X.
| Wet chemical analysis (mg/L) |
||||||
|---|---|---|---|---|---|---|
| No_Comp | Cl_Comp | OH_Comp | Alk_Comp | Tot_Comp | ||
| Ca | 59.03 | 59.13 | 58.81 | 59.12 | 58.92 | |
| Na | 1.28 | 1.20 | 1.38 | 0.93 | 0.72 | |
| P | 27.07 | 26.95 | 27.57 | 26.67 | 26.95 | |
| Cl | 0.00 | 0.92 | 0.00 | 0.00 | 0.53 | |
| F |
5.13 |
4.73 |
4.28 |
5.00 |
4.56 |
|
| Chemical composition (wt. %) | ||||||
| No_Comp |
Cl_Comp |
OH_Comp |
Alk_Comp |
Tot_Comp |
FApth |
|
| CaO | 55.06 | 55.16 | 54.86 | 55.15 | 54.96 | 55.60 |
| Na2O | 1.15 | 1.08 | 1.24 | 0.84 | 0.65 | |
| P2O5 | 41.35 | 41.17 | 42.12 | 40.74 | 41.16 | 42.22 |
| Cl | 0.00 | 0.61 | 0.00 | 0.00 | 0.35 | |
| F | 3.42 | 3.15 | 2.85 | 3.33 | 2.64 | 3.77 |
| Sub-Total | 100.98 | 101.17 | 101.07 | 100.06 | 99.76 | 101.59 |
| -O=F2,Cl2 | 1.44 | 1.46 | 1.20 | 1.40 | 1.19 | 1.59 |
| Total |
99.54 |
99.71 |
99.87 |
98.66 |
98.57 |
100 |
| atom per formula unit (a.p.f.u.) | ||||||
| No_Comp |
Cl_Comp |
OH_Comp |
Alk_Comp |
Tot_Comp |
FApth |
|
| Ca | 4.819 | 4.835 | 4.782 | 4.879 | 4.871 | 5 |
| Na | 0.182 | 0.171 | 0.196 | 0.134 | 0.104 | |
| P | 2.859 | 2.852 | 2.901 | 2.848 | 2.883 | 3 |
| Cl | 0.000 | 0.085 | 0.000 | 0.000 | 0.050 | |
| F | 0.883 | 0.815 | 0.733 | 0.843 | 0.691 | 1 |
| OH | 0.117 | 0.100 | 0.267 | 0.157 | 0.259 | |
| Charge Balance | +0.243 | +0.285 | +0.057 | +0.348 | +0.197 | |
| Charge Balance + (CO3) | 0 | 0 | 0 | 0 | 0 | |
| M site (Ca + Na) | 5.001 | 5.006 | 4.978 | 5.013 | 4.975 | 5 |
| T site (P) | 2.859 | 2.852 | 2.901 | 2.848 | 2.883 | 3 |
| T site + (CO3) | 2.980 | 2.994 | 2.930 | 3.022 | 2.982 | |
| X site (F + Cl + OH) | 1.000 | 1.000 | 1.000 | 1.000 | 1.000 | 1 |