Transformation of meta-stable calcium silicate hydrates to tobermorite: reaction kinetics and molecular structure from XRD and NMR spectroscopy

Table 2 Aqueous silica, aluminum and calcium concentrations from the 10:1 batch reaction.

time (h)	Si_(aq) (mol kg^-1)	Al_(aq) (mol kg^-1)	Ca_(aq) (mol kg^-1)
0.0	0.00165	0.00021	0.00182
3.0	0.00934	0.00050	0.00002
6.0	0.00501	0.00101	0.00002
9.0	0.00312	0.00127	0.00006
15.2	0.00126	0.00140	0.00010
19.0	0.00038	0.00136	0.00021
48.0	0.00154	0.00279	0.00008
24.0	0.00123	0.00146	0.00021
42.0	0.00303	0.00186	0.00005
30.6	0.00057	0.00227	0.00018
24.0	0.00062	0.00186	0.00024
72.0	0.00674	0.00188	0.00004
120.0	0.00286	0.00163	0.00006
47.8	0.00215	0.00257	0.00006
94.5	0.00250	0.00062	0.00006
48.0	0.00163	0.00355	0.00006
190.5	0.00390	0.00034	0.00002
96.5	0.00313	0.00100	0.00003
64.0	0.00823	0.00362	0.00005
89.0	0.00695	0.00201	0.00006
16.0	0.00100	0.00101	0.00010

Standard deviations are ± 4–5 × 10^-4 mol kg^-1 for Si_(aq) and Al_(aq) and at most ± 9 × 10^-5 mol kg^-1 for Ca_(aq).

ISSN: 1467-4866