Gluconate and hexitols effects on C-S-H solubility

This study investigates the effect of gluconate, a carboxylate anion, and three uncharged hexitols, D-sorbitol, d-mannitol D-galactitol on solubility C-S-H. Thermodynamic modeling is used to determine kind amount Ca-organic-silicate-OH complexes that potentially form in conditions studied. All organics with calcium hydroxide. In addition, heteropolynuclear calcium, hydroxide silicate are observed at high pH values concentrations: Ca2Hex2(H3SiO4)2(OH)20, Ca2Hex2(H2SiO4)(OH)2−2 Ca3Gluc2(H3SiO4)2(OH)20, exception mannitol. The strength complexation decreases order gluconate > sorbitol galactitol. adsorption selected portlandite C-S-H systems follows mannitol ~ For C-S-H, typical Langmuir isotherm found only when buffered Ca(OH)2. increases Ca/Si ratio.