A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Citrate sorption on cement hydrates
Abstract The interaction of citrate with hydrated Portland cement and its main hydrates: C-S-H (0.8 ≤ Ca/Si ≤ 1.4), ettringite, monosulfo-, hemi- and monocarboaluminate is investigated. The solubility of citrate-AFm and citrate-AFt was determined. Batch sorption experiments at pH = 13.2 showed that citrate sorbs relatively strongly on AFm phases and ettringite. Citrate sorbed only on the outer surfaces sites of monosulfoaluminate, monocarboaluminate and ettringite resulting in a low sorption capacity of ≈5–8 mmol/kg, while in the case of hemicarboaluminate sorption occurred also in the interlayer resulting in a sorption capacity of ≈1000 mmol/kg. The sorption on C-S-H was found one order of magnitude lower and increased with increasing Ca/Si as its uptake is promoted by the Ca-citrate surface complexes. The sorption coefficients of citrate measured on hydrated Portland cement were with Rd = 10–30 L·kg−1 comparable to the sorption observed on high Ca/Si C-S-H and AFm phases, underlining the strong uptake of citrate in hydrated cements.
Citrate sorption on cement hydrates
Abstract The interaction of citrate with hydrated Portland cement and its main hydrates: C-S-H (0.8 ≤ Ca/Si ≤ 1.4), ettringite, monosulfo-, hemi- and monocarboaluminate is investigated. The solubility of citrate-AFm and citrate-AFt was determined. Batch sorption experiments at pH = 13.2 showed that citrate sorbs relatively strongly on AFm phases and ettringite. Citrate sorbed only on the outer surfaces sites of monosulfoaluminate, monocarboaluminate and ettringite resulting in a low sorption capacity of ≈5–8 mmol/kg, while in the case of hemicarboaluminate sorption occurred also in the interlayer resulting in a sorption capacity of ≈1000 mmol/kg. The sorption on C-S-H was found one order of magnitude lower and increased with increasing Ca/Si as its uptake is promoted by the Ca-citrate surface complexes. The sorption coefficients of citrate measured on hydrated Portland cement were with Rd = 10–30 L·kg−1 comparable to the sorption observed on high Ca/Si C-S-H and AFm phases, underlining the strong uptake of citrate in hydrated cements.
Citrate sorption on cement hydrates
Guidone, Rosa Ester (author) / Gaona, Xavier (author) / Winnefeld, Frank (author) / Altmaier, Marcus (author) / Geckeis, Horst (author) / Lothenbach, Barbara (author)
2023-12-03
Article (Journal)
Electronic Resource
English
AFm phases , C-S-H , Sorption , Citrate
Surface Relaxivity of Cement Hydrates
| Tema Archive | 2014
Bonding between cement hydrates and steel
| TIBKAT | 1976
Interaction Between Portland Cement Hydrates and Polynapthalene Sulfonates
| British Library Conference Proceedings | 1997
Interaction between Portland cement hydrates and polynaphtalene sulfonates
| Tema Archive | 1997
Microstructure of cement hydrates containing calcium lignosulfonate admixture
| Springer Verlag | 1977