Alkali-activated cement composition

Patent metadata

Field	Value
Publication number	US-12448333-B2
Application number	US-202318363398-A
Country	US
Kind code	B2
Filing date	Aug 1, 2023
Priority date	Aug 1, 2023
Publication date	Oct 21, 2025
Grant date	Oct 21, 2025

Abstract

A cement composition includes a curable component in an amount of 10 to 25 wt. %; a fine aggregate (FA) in an amount of 20 to 40 wt. %; a coarse aggregate (CA) in an amount of 40 to 50 wt. %; and an alkaline component in an amount of 5 to 15 wt. %, each wt. % based on the total weight of the cement composition. The curable component includes a cementitious material having an average particle size (D 50 ) of 10 to 17 micrometers (μm), a limestone powder (LSP) material having a D 50 of 13 to 19 μm, a red mud (RM) material having a D 50 of 30 to 36 μm, a silicomanganese fume (SMF) material having a D 50 of 28 to 34 μm, and a natural pozzolan (NP) material having a D 50 of 13 to 19 μm.

First claim

The invention claimed is:

1. A cement composition, comprising:
a curable component in an amount of 10 to 25 wt. % based on a total weight of the cement composition;
wherein the curable component comprises a cementitious material, a limestone powder (LSP) material, a red mud (RM) material, a silicomanganese fume (SMF) material, and a natural pozzolan (NP) material;
a fine aggregate (FA) comprising sand in an amount of 20 to 40 wt. % based on the total weight of the cement composition;
a coarse aggregate (CA) comprising crushed limestone in an amount of 40 to 50 wt. % based on the total weight of the cement composition;
an alkaline component in an amount of 5 to 15 wt. %, based on the total weight of the cement composition;
wherein the alkaline component comprises an alkali metal hydroxide and an alkali silicate;
wherein the cementitious material has an average particle size (D 50 ) of 10 to 17 micrometers (μm);
wherein the LSP material has a D 50 of 13 to 19 μm;
wherein the RM material has a D 50 of 30 to 36 μm;
wherein the SMF material has a D 50 of 28 to 34 μm;
wherein the NP material has a D 50 of 13 to 19 μm;
wherein particles of the cementitious material, the LSP material, and the NP material have angular, irregular, and flake-like shapes; and
wherein particles of the RM material, and the SMF material have smooth surfaces and spherical shapes.

2. The cement composition of claim 1 , wherein:
the cementitious material is present in the curable component at a concentration of 5 to 35 wt. %;
the LSP material is present in the curable component at a concentration of 5 to 15 wt. %;
the RM material is present in the curable component at a concentration of 5 to 25 wt. %;
the SMF material is present in the curable component at a concentration of 5 to 25 wt. %; and
the NP material is present in the curable component at a concentration of 25 to 55 wt. %, each wt. % based on a total weight of the cementitious material.

3. The cement composition of claim 1 , wherein the cementitious material comprises at least one selected from the group consisting of portland cement, pozzolan cement, gypsum cement, aluminous cement, silica cement, and alkaline cement.

4. The cement composition of claim 1 , wherein the cementitious material is type I ordinary portland cement (OPC).

5. The cement composition of claim 1 , wherein the cementitious material comprises 81 to 88 wt. % CaO, 3 to 9 wt. % SiO 2 , 0.5 to 2 wt. % Al 2 O 3 , 2.5 to 9 wt. % FeO, 0.1 to 0.3 wt. % K 2 O, 0.2 to 0.8 wt. % MgO, each wt. % based on a total weight of the cementitious material.

6. The cement composition of claim 1 , wherein the LSP material comprises 80 to 86 wt. % CaO, 8 to 15 wt. % SiO 2 , 1 to 4 wt. % Al 2 O 3 , 0.5 to 2.5 wt. % FeO, each wt. % based on a total weight of the LSP material.

7. The cement composition of claim 1 , wherein the NP material comprises 10 to 17 wt. % CaO, 33 to 40 wt. % SiO 2 , 7 to 13 wt. % Al 2 O 3 , 25 to 33 wt. % FeO, 0.5 to 1.5 wt. % K 2 O, 2 to 7 wt. % MgO, 1 to 3 wt. % TiO 2 , each wt. % based on a total weight of the NP material.

8. The cement composition of claim 1 , wherein the RM material comprises 2 to 7 wt. % CaO, 7 to 13 wt. % SiO 2 , 11 to 17 wt. % Al 2 O 3 , 50 to 58 wt. % FeO, 8 to 16 wt. % Na 2 O, 2 to 10 wt. % MgO, 1 to 7 wt. % TiO 2 , each wt. % based on a total weight of the RM material.

9. The cement composition of claim 1 , wherein the SMF material comprises 1 to 5 wt. % CaO, 10 to 18 wt. % SiO 2 , 70 to 80 wt. % MnO, 1 to 7 wt. % FeO, 0.05 to 0.2 wt. % K 2 O, 1 to 5 wt. % MgO, each wt. % based on a total weight of the SMF material.

10. The cement composition of claim 1 , wherein the FA comprises sand having a specific gravity of 2.6 to 2.7, and wherein the CA comprises limestone having a specific gravity of 2.5 to 2.6.

11. The cement composition of claim 1 , wherein the alkali metal hydroxide is sodium hydroxide (NaOH), and the alkali silicate is sodium silicate (Na 2 SiO 3 ), and wherein a weight ratio of the NaOH to the Na 2 SiO 3 is in a range of 1:1 to 1:4.

12. A method of producing a cured specimen, the method comprising:
mixing the cement composition of claim 1 with water to form a mortar composition;
casting the mortar composition in a mold to form a molded composition; and
curing the molded composition for 12 to 48 hours thereby forming the cured specimen;
wherein the curing is conducted under an ambient air condition or a steam condition.

13. The method of claim 12 , wherein the cured specimen has a compressive strength of 10 to 50 MPa as determined by ASTM C39.

14. The method of claim 12 , wherein the cured specimen has a modulus of elasticity of 5 to 20 GPa as determined by ASTM C469.

15. The method of claim 12 , wherein the cured specimen has a split tensile strength of 1 to 4 MPa as determined by ASTM C496.

16. The method of claim 12 , wherein the cured specimen has a drying shrinkage of 90 to 650 microstrains as determined by ASTM C596.

17. The method of claim 12 , wherein the cured specimen has a residual strength of 10 to 35 MPa after an acid attack as determined by ASTM C1898.

18. The method of claim 12 , wherein the cured specimen has a residual strength of 5 to 40 MPa after a sulfate attack as determined by ASTM C1012.

19. The method of claim 12 , wherein the cured specimen has a non-steady state chloride migration coefficient (D nssm ) in a range of 17.5 to 29.6×10 −12 m 2 /s as determined by ASTM C1202.

20. The method of claim 12 , wherein the cured specimen has a chloride diffusion coefficient (D a ) in a range of 53×10 −12 to 17.6×10 −12 m 2 /s for the free chloride and from 35.1×10 −12 to 7.8×10 −12 m 2 /s for the total chloride as determined by ASTM C1152 and C1156.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Al-Duais Ibrahim Nabil Ali
• Ahmad Shamsad
• Al-Osta Mohammad
• Maslehuddin Mohammed
• Al-Dulaijan Salah Uthman
• Saleh Tawfik Abdo

Classifications

• C04B18/0409

  Waste from the purification of bauxite, e.g. red mud · CPC title

• C04B2111/34

  Non-shrinking or non-cracking materials · CPC title

• C04B2201/50

  for the mechanical strength · CPC title

• C04B22/062

  of the alkali or alkaline-earth metals · CPC title

• C04B14/045

  Alkali-metal containing silicates, e.g. petalite (waterglass C04B12/04) · CPC title