Structural characterization of geomaterial foams — Thermal behavior

Reply to the J. Provis and S.A. Bernal comment about the article “Structural characterization of geomaterial foams. Thermal behavior” published in J. Non-Cryst. Solids, 2011

“…If we assume that all hydroxide is transformed, the quantity of hydrogenocarbonates formed in contact with air should be 1.4 wt.% in the case of potassium and 1.5 wt.% in the case of sodium samples, in agreement with TGA results. According to this hypothesis, the infrared at 880 cm − 1 band should be attributed to the presence of potassium or sodium bicarbonates [2,8]. These species also explains the presence of the band at 1300 cm − 1 attributed to νCO 3 2 − .…”

“…We have read with interest the comment of J. Provis and S.A. Bernal [1] about the thermal behavior and the interpretation of NMR spectra of inorganic foams based on geopolymer materials [2]. We wish to thank in the present contribution, the authors for their comments and their interest of this work.…”

“…On the other hand, the analysis of thermo-gravimetric data presented in [2], shows the presence of a mass-loss peak at 200°C-230°C. This peak has been partially attributed to the elimination of bicarbonate species, detected by mass spectroscopy in potassium and sodium foams as already shown in previous work [9].…”

“…In order to justify the assignment proposed in our work [2], we have assumed that the avoidance of Al-O-Al associations in neighboring tetrahedral is respected (Lowenstein's rule). Then, the analysis of 27 Al NMR spectra (Al n (nSi), n = 3 and 4) results more relevant that of 29 Si NMR spectra (Si n (mAl) environments with m ≤ n), taking into account the number of possible components.…”

Investigation on the Activating Effect of Na2co3 and Naoh on Slag

“…It is generally accepted that alkali activated materials (AAM) is considered to be the most potential product in replacing currently widely used traditional cement in terms of mechanical properties and durabilities e.g. fire resistance [1,2] and heavy metal immobilization [3][4][5][6][7]. Slag has been considered as the most potential raw material in AAM system, and the relevant properties and influential factors of slag-based AAM have been extensively studied from the early stage [8,9].…”