Effect of Polymer Surfactants on the Inhibition of Beta-dicalcium Silicate Decomposition in Sodium Aluminate Solution

The decomposition behavior of synthetic beta-2CaO center dot SiO2 by adding sodium polyacrylate (NaPAA), polyethylene glycol (PEG) and their mixture at 80 degrees C in sodium aluminate solution was investigated. The SiO2 concentration in the reacted sodium aluminate solution decreases as the polymer surfactant charge increases, but does not change obviously when each surfactant is added over 12.5 mg/L. The amount of CaCO3, hydro-garnet and sodium aluminum silicate hydrate in the decomposed solid with polymer surfactant addition is much smaller than that without surfactant addition. The losses of Na2O and Al2O3 are greatly decreased due to polymer surfactant addition. The inhibition sequence of beta-2CaO center dot SiO2 decomposition by polymer surfactants in sodium aluminate solution is mixture of NaPAA and PEG, NaPAA, PEG.