METHODS FOR MAKING GEOPOLYMERIC CEMENTS AND CEMENTS RESULTING FROM THESE METHODS

摘要

The invention concerns a method for making geopolymeric cement consisting in producing a reaction mixture containing (parts in weight of dry matter):reagent (I):100 parts by weight of aluminosilicate oxide [Si2O5,Al2O2]9[Si2O5,Al2(OH)3], or simplified below as (Si2O5Al2O2)(IV-V); reagent (II): 30-55 parts of alkali silicate in which the mol ratio M2O/SiO2 ranges between 0.5 and 0.8, M representing Na and/or K or the mixture Na+K; reagent (III): 80-110 parts of basic silicate, in glass state, consisting partly of gehlenite, akermanite and wollastonite; reagent (IV): 150-250 parts of alkali aluminosilicate containing at least 5 % by weight of (Na2O+K2O), preferably at least 8 % by weight; then in hardening said mixture by adding water: After hardening the geopolymeric cements are made of two distinct phases: a) a glass phase having a MAS NMR spectrum for <29>Si with a band ranging between -85 and -89ppm, and a MAS NMR spectrum for <27>Al with a resonance at 54-58ppm; b) a crystalline phase having a MAS NMR spectrum for <29>Si with a band ranging between -90ppm and -115ppm, and a MAS NMR spectrum for <27>Al with a resonance at 57ppm.