One step process of making sustainable hybrid magnesium cement

Patent metadata

Field	Value
Publication number	US-2021323870-A1
Application number	US-202117234131-A
Country	US
Kind code	A1
Filing date	Apr 19, 2021
Priority date	Apr 20, 2020
Publication date	Oct 21, 2021
Grant date	—

Abstract

An exemplary process for forming a cured hybrid magnesium cement composition may include first combining a mixture of magnesium-containing material, a metal silicate inorganic polymer having a repeat unit of SiP2O7, and a salt having a non-metallic oxide anion, and then mixing the mixture with water.

First claim

What is claimed is:

1 . A process for forming a cured hybrid magnesium cement (HMC) composition, the process comprising:
combining together a mixture of magnesium-containing material, a metal silicate inorganic polymer having a repeat unit of SiP 2 O 7 , and a salt having a non-metallic oxide anion; and mixing the mixture with water.

2 . The process of claim 1 , further comprising adding hydraulic additives, activators, linear silicon polymer, and/or sand.

3 . The process of claim 1 , wherein the magnesium-containing material includes calcium carbonate in the amount from 0 wt. % to 70 wt. % of the magnesium-containing material, calcium oxide in the less than 10% of the magnesium-containing material, magnesium carbonate in the amount of 0 wt. % to 25 wt. % of the magnesium-containing material, and magnesium oxide in the amount from 18 wt. % to 70 wt. % of the magnesium-containing material.

4 . The process of claim 1 , wherein the magnesium-containing material is a light-burn, hard-burn or dead-burn grade magnesite, dolomite, pyroxenite, amphibolite, serpentine, dunite, or chlorite having a weight loss ranging from 23-28 dry wt. % relative to an uncalcined magnesium-containing material as measured by weighing the dry magnesium-containing material after calcining relative to before calcining.

5 . The process of claim 2 , wherein the hydraulic additive includes a ground granulated blast-furnace slag.

6 . The process of claim 2 , further comprising adding a silicate source including calcium silicates and calcium aluminate silicate.

7 . The process of claim 2 , comprising adding a silicate source including at least one of a metakaolin, fly ash, slag, biomass ash and bottom ash.

8 . The process of claim 1 , wherein the salt is a phosphate salt capable of being solubilized in the amount ranging from 1.5 wt. % to 11 wt. % on a dry weight basis.

9 . The process of claim 1 , further comprising adding magnesium oxide, wherein a weight ratio of the salt to magnesium oxide ranges from 0.1 to 1.2.

10 . The process of claim 1 , wherein the magnesium-containing material composition includes a light-burn, hard-burn, or dead-burn grade magnesite and a salt having a non-metal oxide anion.

11 . The process of claim 2 , comprising adding a cement activator source including at least one of a free lime, hydrated lime, alkali hydroxide, sodium sulfate and sodium carbonate.

12 . The process of claim 1 , wherein the metal silicate inorganic polymer chains having at least 60 repeat units of SiP 2 O 7 .

13 . The process of claim 1 , wherein the metal silicate inorganic polymer is formed during the curing of the hybrid magnesium cement composition.

14 . The process of claim 2 , comprising adding the linear silicon polymer including at least one silicone resin polymer comprising a siloxane-oxygen structure R—SiO, where R represents alkyl and aryl organic groups.

15 . The process of claim 14 , wherein the R—SiO siloxane-oxygen resin polymer ranges from 0.03 wgt. % to 5 wgt. % and contains at least 40 wgt. % SiO 2 , where the R represents a phenol:methyl ratio of 0.6:1, a molecular weight of <5,000 daltons and a Tg between 40° C. and 70° C.

16 . A process comprising:
first mixing together a mixture of a magnesium-containing material, a linear silicone polymer, a salt, and at least one of a hydraulic additive, a cement activator, and sand; and then mixing water with the mixture to form a hybrid magnesium cement (HMC) composition.

17 . The process of claim 16 , further comprising spraying, shotcreting, 3D printing, or casting the HMC composition into at least one mold.

18 . The process of claim 17 , further comprising testing the HMC composition to failure, and measuring at least one of a compressive strength, a flexural strength, and a tensile strength of the HMC composition.

19 . The process of claim 18 , wherein the testing is performed according to test method ASTM C109 or C39 for compression, ASTEM C78 or C293 for flexure strength, and ASTM C496 for tension.

20 . The process of claim 16 , wherein the magnesium-containing material includes at least magnesium oxide.

21 . The process of claim 16 , wherein the salt is a dipotassium phosphate.

22 . A hybrid magnesium cement (HMC) formed from a process comprising:
combining a mixture of magnesium-containing material, a metal silicate inorganic polymer having a repeat unit of SiP 2 O 7 , and a salt having a non-metallic oxide anion; and mixing the mixture with water.

Assignees

• Univ Wayne State

Inventors

• Wu Hwai-Chung

Classifications

• C04B2111/00019

  Carbon dioxide sequestration · CPC title

• C04B22/10

  containing carbon in the anion, e.g. carbonates · CPC title

• Y02W30/91

  Use of waste materials as fillers for mortars or concrete · CPC title

• C04B28/344 Primary

  the phosphate binder being present in the starting composition solely as one or more phosphates · CPC title

• B33Y70/00

  Materials specially adapted for additive manufacturing · CPC title