Adsorption of methylene blue as a descriptor of C–S–H nanostructure

The adsorption of methylene blue (MB) on C–S–H surfaces (C/S ratios 0.60–1.80) and its dependence on C–S–H nanostructure was investigated. UV–VIS spectroscopy was used to obtain the adsorption–desorption isotherms at 23°C, 35°C and 50°C. The character of the UV–VIS spectra and the nature of the C–S–H–MB interaction are discussed. Several sorption models including those due to Langmuir, Harkins–Jura, Halsey, Henderson, and Freundlich are fitted …