Tailored geopolymer composite binders for cement and concrete applications

Abstract

A geopolymer composite binder is provided herein, the composite binder including (i) at least one fly ash material having less than or equal to 15 wt % of calcium oxide; (ii) at least one gelation enhancer; and (iii) at least one hardening enhancer having a different composition from a composition of the at least one fly ash material.

1 . A dry mixture for a geopolymer binder, comprising:
 (i) at least one fly ash material comprising less than or equal to 15 wt % of calcium oxide;   (ii) at least one gelation enhancer; and   (iii) at least one hardening enhancer having a different composition from a composition of the at least one fly ash material.   
     
     
         2 . The dry mixture of  claim 1 , wherein the at least one fly ash material is a Class F fly ash material. 
     
     
         3 . The dry mixture of  claim 1 , wherein the at least one gelation enhancer comprises metakaolin, micron or nano sized silica particles, a pozzolanic material that has a high dissolution rate in alkaline solution, or combinations thereof. 
     
     
         4 . The dry mixture of  claim 1 , wherein the at least one gelation enhancer comprises metakaolin. 
     
     
         5 . The dry mixture of  claim 1 , wherein the at least one hardening enhancer comprises blast furnace slag, Class F fly ash having more than 8 wt % calcium oxide, Class C fly ash, gypsum, an alkali-earth compound, a calcium rich pozzolanic material, a calcium rich zeolite, calcium hydroxide, aluminum hydroxide or combinations thereof. 
     
     
         6 . The dry mixture of  claim 1 , wherein the at least one hardening enhancer comprises blast furnace slag, Class C fly ash, gypsum, calcium rich chabazite, calcium rich clinoptilolite, calcium hydroxide, aluminum hydroxide, vitreous calcium aluminosilicate, kiln dust, bottom ash or combinations thereof. 
     
     
         7 . The dry mixture of  claim 6 , wherein the at least one hardening enhancer comprises blast furnace slag or Class C fly ash. 
     
     
         8 . The dry mixture of  claim 1 , comprising at least two hardening enhancers. 
     
     
         9 . The dry mixture of  claim 1 , further comprising a setting modifier. 
     
     
         10 . The dry mixture of  claim 9 , wherein the setting modifier comprises boric acid, borax, a nitrate salt, phosphoric acid, sodium sulfate, sodium phosphate, calcium chloride, or sodium citrate. 
     
     
         11 . The dry mixture of  claim 2 , wherein:
 (i) the at least one fly ash material comprises at least about 15 wt % of the dry mixture;   (ii) the at least one gelation enhancer comprises greater than zero and less than about 80 wt % of the dry mixture; and   (iii) the at least one hardening enhancer comprises greater than zero and less than about 80 wt % of the dry mixture.   
     
     
         12 . The dry mixture of  claim 11 , wherein:
 (i) the at least one fly ash material comprises about 15 wt % to about 90 wt % of the dry mixture;   (ii) the at least one gelation enhancer comprises about 5 wt % to about 80 wt % of the dry mixture; and   (iii) the at least one hardening enhancer comprises about 5 wt % to about 80 wt % of the dry mixture.   
     
     
         13 . The dry mixture of  claim 12 , wherein:
 (i) the at least one fly ash material comprises at least about 60 wt % of the dry mixture;   (ii) the at least one gelation enhancer comprises about 10 wt % to about 25 wt % of the dry mixture; and   (iii) the at least one hardening enhancer comprises about 10 wt % to about 25 wt % of the dry mixture.   
     
     
         14 . The dry mixture of  claim 2 , wherein the at least one fly ash material comprises between 8 and 15 wt % calcium oxide. 
     
     
         15 . The dry mixture of  claim 2 , wherein the at least one fly ash material comprises between 1 and 8 wt % calcium oxide. 
     
     
         16 . A geopolymer composite binder, made by combining the dry mixture of  claim 1  and an activator. 
     
     
         17 . The binder  claim 16 , wherein the activator comprises an activator alkaline solution comprising a metal hydroxide and a metal silicate. 
     
     
         18 . The binder of  claim 17 , wherein:
 the gelation enhancer comprises metakaolin;   a SiO 2 /Al 2 O 3  molar ratio of the binder ranges from about 2.5 to about 6.0;   a M 2 O/Al 2 O 3  molar ratio of the binder ranges from about 0.7 to 1.5, where M comprises Na, K or Li;   a H 2 O/M 2 O molar ratio of the binder ranges from about 5 to 18;   a water to solid weight ratio ranges from about 0.12 to about 0.8;   a Na 2 O to the solid weight ratio ranges from about 0.01 to about 0.25;   the SiO 2  to solid weight ratio ranges from about 0.01 to about 0.25;   the SiO 2  to the Na 2 O solid weight ratio ranges from about 0.1 to about 2.0; and   the activator alkaline solution to the solid weight ratio ranges from about 0.20 to about 0.85.   
     
     
         19 . A concrete or mortar geopolymer composition made by combining the binder of  claim 18  with at least one aggregate. 
     
     
         20 . The composition of  claim 19 , wherein the composition has a seven day compressive strength of at least about 10000 psi and a room temperature setting time of 30 minutes to 3 hours. 
     
     
         21 . A concrete or mortar geopolymer composition which has a seven day compressive strength of at least about 10000 psi, a setting time of 30 minutes to 3 hours and a setting temperature between 20 and 75° C. 
     
     
         22 . The composition of  claim 21 , wherein the composition has a seven day compressive strength of 10000 psi to 12530 psi and a setting time of 1 to 3 hours at room temperature. 
     
     
         23 . The composition of  claim 21 , wherein the composition is made by mixing a dry mixture, an activator solution and at least one aggregate. 
     
     
         24 . The composition of  claim 23 , wherein:
 the dry mixture comprises:
 (i) at least one fly ash material comprising less than or equal to 15 wt % of calcium oxide; 
 (ii) at least one gelation enhancer; and 
 (iii) at least one hardening enhancer having a different composition from a composition of the at least one fly ash material; and 
   the activator solution comprises an alkaline solution comprising a metal hydroxide and a metal silicate.   
     
     
         25 . The composition of  claim 21 , wherein the composition comprises a mortar composition. 
     
     
         26 . The composition of  claim 21 , wherein the composition comprises a concrete composition. 
     
     
         27 . A method of making a concrete or mortar composition, comprising mixing (i) at least one fly ash material comprising less than or equal to 15 wt % of calcium oxide; (ii) at least one gelation enhancer; (iii) at least one hardening enhancer, (iv) at least one activator and (v) at least one aggregate to form the composition. 
     
     
         28 . The method of  claim 26 , wherein the method comprises:
 providing a pre-mixed dry mixture comprising (i) the at least one fly ash material comprising less than or equal 15 wt % of calcium oxide; (ii) the at least one gelation enhancer; and (iii) the at least one hardening enhancer; and   mixing the dry mixture with the at least one activator and the at least one aggregate.   
     
     
         29 . The method of  claim 28 , further comprising providing the composition into a building or a road under construction, wherein the step of mixing the dry mixture with the at least one activator and the at least one aggregate occurs at a site of the construction. 
     
     
         30 . The method of  claim 27 , further comprising providing the composition into a building or a road under construction, wherein:
 (i) the at least one fly ash material comprising less than or equal 15 wt % of calcium oxide; (ii) the at least one gelation enhancer; and (iii) the at least one hardening enhancer are mixed on or off the construction site; and   (iv) the at least one activator and (v) the at least one aggregate are mixed with other components of the composition on the construction side.   
     
     
         31 . The method of  claim 27 , wherein the at least one fly ash material is a Class F fly ash material. 
     
     
         32 . The method of  claim 27 , wherein the at least one gelation enhancer comprises metakaolin, micron or nano sized silica particles, a pozzolanic material that has a high dissolution rate in alkaline solution, or combinations thereof. 
     
     
         33 . The method of  claim 27 , wherein the at least one gelation enhancer comprises metakaolin. 
     
     
         34 . The method of  claim 27 , wherein the at least one hardening enhancer comprises blast furnace slag, Class F fly ash having more than 8 wt % calcium oxide, Class C fly ash, gypsum, an alkali-earth compound, a calcium rich pozzolanic material, a calcium rich zeolite, calcium hydroxide, aluminum hydroxide or combinations thereof. 
     
     
         35 . The method of  claim 34 , wherein the at least one hardening enhancer comprises blast furnace slag, Class C fly ash, gypsum, calcium rich chabazite, calcium rich clinoptilolite, vitreous calcium aluminosilicate, calcium hydroxide, aluminum hydroxide, vitreous calcium aluminosilicate, kiln dust, bottom ash or combinations thereof. 
     
     
         36 . The method of  claim 27 , further comprising mixing a setting modifier. 
     
     
         37 . The method of  claim 36 , wherein the setting modifier comprises boric acid, borax, a nitrate salt, phosphoric acid, sodium sulfate, sodium phosphate, calcium chloride, or sodium citrate. 
     
     
         38 . The method of  claim 28 , wherein:
 (i) the at least one fly ash material comprises at least about 15 wt % of the dry mixture;   (ii) the at least one gelation enhancer comprises greater than zero and less than about 80 wt % of the dry mixture; and   (iii) the at least one hardening enhancer comprises greater than zero and less than about 80 wt % of the dry mixture.   
     
     
         39 . The method of  claim 38 , wherein:
 (i) the at least one fly ash material comprises about 15 wt % to about 90 wt % of the dry mixture;   (ii) the at least one gelation enhancer comprises about 5 wt % to about 80 wt % of the dry mixture; and   (iii) the at least one hardening enhancer comprises about 5 wt % to about 80 wt % of the dry mixture.   
     
     
         40 . The method of  claim 39 , wherein:
 (i) the at least one fly ash material comprises at least about 60 wt % of the dry mixture;   (ii) the at least one gelation enhancer comprises about 10 wt % to about 25 wt % of the dry mixture; and   (iii) the at least one hardening enhancer comprises about 10 wt % to about 25 wt % of the dry mixture.   
     
     
         41 . The method of  claim 38 , wherein the fly ash material comprises between 8 and 15 wt % calcium oxide. 
     
     
         42 . The method of  claim 38 , wherein the fly ash material comprises between 1 and 8 wt % calcium oxide. 
     
     
         43 . The method  claim 27 , wherein the activator comprises an alkaline solution comprising a metal hydroxide and a metal silicate and the aggregate comprises a fine aggregate and a coarse aggregate. 
     
     
         44 . The method of  claim 43 , wherein:
 the gelation enhancer comprises metakaolin;   a binder is formed by mixing (i) the at least one fly ash material comprising less than or equal to 15 wt % of calcium oxide; (ii) the at least one gelation enhancer; (iii) the at least one hardening enhancer, (iv) the at least one activator;   a SiO 2 /Al 2 O 3  molar ratio of the binder ranges from about 2.5 to about 6.0;   a M 2 O/Al 2 O 3  molar ratio of the binder ranges from about 0.7 to 1.5, where M comprises Na, K or Li; and   a H 2 O/M 2 O molar ratio of the binder ranges from about 5 to 18.   
     
     
         45 . The method of  claim 27 , wherein the method comprises setting the composition in 30 minutes to 3 hours at setting temperature between 20 and 75° C. and curing the composition for at least 24 hours at a curing temperature between 20 and 75° C. to achieve a seven day compressive strength of at least about 10000 psi. 
     
     
         46 . The method of  claim 45 , wherein the composition has a seven day compressive strength of 10000 psi to 12530 psi and a setting time of 1 to 3 hours at room temperature. 
     
     
         47 . The method of  claim 27 , wherein the composition comprises a mortar composition. 
     
     
         48 . The method of  claim 27 , wherein the composition comprises a concrete composition. 
     
     
         49 . A dry mixture for a geopolymer binder, comprising:
 (i) a Class F fly ash material comprising at least 60 wt % of the dry mixture;   (ii) a metakaolin gelation enhancer comprising greater than zero and less than 25 wt % of the dry mixture; and   (iii) a blast furnace slag or Class C fly ash hardening enhancer comprising greater than zero and less than 25 wt % of the dry mixture.   
     
     
         50 . A method of making a concrete or mortar composition, comprising:
 forming a composition by mixing at least one activator and at least one aggregate with a dry mixture comprising:   (i) a Class F fly ash material comprising at least 60 wt % of the dry mixture;   (ii) a metakaolin gelation enhancer comprising greater than zero and less than 25 wt % of the dry mixture; and   (iii) a blast furnace slag or Class C fly ash hardening enhancer comprising greater than zero and less than 25 wt % of the dry mixture; and   setting the composition in 30 minutes to 3 hours at setting temperature between 20 and 75° C., and curing the composition for at least 24 hours at a curing temperature between 20 and 75° C. to form the concrete or mortar composition having seven day compressive strength of at least about 10000 psi.