GEOPOLYMER CEMENT OF THE CALCIUM FERRO-ALUMINOSILICATE POLYMER TYPE AND PRODUCTION PROCESS.

摘要

The invention relates to a geopolymer binder or cement of ferro-aluminosilicate [-Fe-O-Si-O-Al-O-] polymer type which, after curing, consists of a geopolymer compound in which some of the Al atoms are substituted with Fe atoms, the whole satisfying the following raw formula: (Ca,Na,K)⋠(FeO)x⋠(SiOAlO)1-x⋠(SiO)< sub>y in which "x" is less than or equal to 0.5 and "y" is between 0 and 25. This geopolymer binder or cement is the result of the geopolymerization of calcium geopolymer type with geological elements rich in iron oxides and in ferro-kaolinite, coming from the weathering of acid rocks such as granite and gneiss, or of basic (mafic) rocks such as basalt and gabbro. The process for manufacturing this geopolymer binder or cement consists in treating said geological elements at a temperature of 600 to 850°C. During this heat treatment, all the iron oxides [goethite FeO(OH) + magnetite Fe3O4] are transformed to hematite Fe2O3 and the ferro-kaolinite becomes ferro-metakaolin of Fe-MK-750 type and then these are made to react with a reaction mixture of calcium geopolymer type.