VERFAHREN ZUR HERSTELLUNG EINES GEOPOLYMEREN BINDEMITTELS GEEIGNET ZUR STABILISIERUNG, VERFERTIGUNG UND KONSOLIDIERUNG VON ABFALLSTOFFEN ODER TOXISCHEN MATERIALIEN

摘要

The method of the invention provides a geopolymeric binder in powder, used for the ultra rapid treatment of materials, soils or mining tailings, containing toxic wastes. The geopolymeric binder has a setting time equal to or greater than 30 minutes at a temperature of 20 DEG C. and a hardening rate such as to provide compression strengths (Sc) equal to or greater than 15 MPa, after only 4 hours at 20 DEG C., when tested in accordance with the standards applied to hydraulic binder mortars having a binder/sand ratio equal to 0.38 and a water/binder ratio between 0.22 and 0.27. The preparation method includes the following three reactive constituents: a) an alumino-silicate oxide (Si2O5,Al2O2) in which the Al cation is in (IV-V) coordination as determined by MAS-NMR analytical spectroscopy for 27Al; b) a disilicate of sodium and/or potassium (Na2,K2)(H3SiO4)2; c) a silicate of calcium where the molar ratios between the three reactive constituents being equal to or between such that where Ca++ designates the calcium ion belonging to a weakly basic silicate of calcium whose atomic ratio Ca/Si is lower than 1.