Tricalcium Silicate-Lignosulfonate-Water

Conduction calorimetric curves of C3S hydrated in the presence of 0.3% calcium lignosulfonate show that the induction period is extended from seven hours to about twenty hours. At 0.5% addition, the hydration of C3S is completely inhibited.1 1 Other studies have shown that addition of small amounts of different types of CLS (0.5%) to C3S pastes retard setting indefinitely, although some of them contained calcium chloride. XRD showed absence of calcium hydroxide in these pastes.  

The TG and DTA techniques have been used to study the effect of 0.5% CLS on C3S hydration. Free lime and combined water contents were determined at different times of hydration. The initial rate of hydration of C3 S was retarded. At a dosage of 0.8 %, the hydration is inhibited up to thirty 

DTA was used by Ramachandranto explain the adsorption-desorption of calcium lignosulfonate in the C3S-H2O system. 00[i3] xhe adsorption and desorption curves for C3S containing CLS are given in Fig. 5. Lignosulfonate does not adsorb on the anhydrous C3S in anonaqueous system. A 

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Tricalcium Silicate-Tricalcium Aluminate-Lignosulfonate-Water System... 

Ramachandran, V. S., Differential Thermal Investigation of the System Tricalcium Silicate-Calcium Lignosulfonate-Water in the Presence of Tricalcium Aluminate and its Hydrates, 3rd Int. Conf. Therm. Analysis, Davos, Switzerland, pp. 255-267 (1971)... 

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