Calcium-alumino-silicate-hydrate nano-seeds suspension and preparation method thereof

Patent metadata

Field	Value
Publication number	US-11312659-B2
Application number	US-202017068926-A
Country	US
Kind code	B2
Filing date	Oct 13, 2020
Priority date	Mar 5, 2020
Publication date	Apr 26, 2022
Grant date	Apr 26, 2022

Abstract

The invention discloses a calcium-alumino-silicate-hydrate nano-seeds suspension and preparation method thereof. The preparation method of calcium-alumino-silicate-hydrate nano-seeds suspension includes the following steps: dropwise adding the aqueous solution of calcium source, the aqueous solution of silicon source and the aqueous solution of aluminum source to the solution of polycarboxylate superplasticizer, and adjusting the pH value to 10.0˜13.5, and continuously stirring to obtain the calcium-alumino-silicate-hydrate nano-seeds suspension. The beneficial effect in the present invention is: the calcium-alumino-silicate-hydrate nano-seeds has small particle size, good dispersion stability, and it can effectively improve the early hydration and mechanical performance of cement-based materials, and has good application prospects; the preparation process is simple, without washing, drying, ultrasonic dispersion and other subsequent processes, suitable for large-scale production.

First claim

What is claimed is:

1. A preparation method of calcium-alumino-silicate-hydrate nano-seeds suspension, including the following steps:
dropwise adding an aqueous solution of calcium source, an aqueous solution of silicon source and an aqueous solution of aluminum source to a solution of polycarboxylate superplasticizer, adjusting a pH value to 10.0˜13.5, and continuously stirring to obtain the calcium-alumino-silicate-hydrate nano-seeds suspension, wherein the calcium to silicon molar ratio is 0.2 to 1.8, and the aluminum to silicon molar ratio is 0.01 to 1.0,
wherein the stirring is carried out at a temperature of 5˜60° C. for 0.5˜24 h and nitrogen gas is supplied during the stirring to prevent carbonization;
wherein raw materials for synthesizing polycarboxylate superplasticizer comprises methacrylic acid and methacrylate, wherein the methacrylic acid to methacrylate molar ratio is 2:1 to 10:1;
wherein the polycarboxylate superplasticizer has a molecular weight of 10000 to 200000, a side chain contains containing 45 to 200 ethylene oxide units and a polymer dispersion index of 1.0 to 5.0;
wherein the solution of polycarboxylate superplasticizer having a solid content of 30%-50% is obtained by the following steps:
dispersing the polycarboxylate superplasticizer into water, and
stirring at a speed of 200˜2000 r/min for 0.5˜2 h.

2. The preparation method of the calcium-alumino-silicate-hydrate nano-seeds suspension according to claim 1 , wherein the aqueous solution of calcium source is one or more of calcium formate, calcium acetate, calcium nitrate, calcium bicarbonate and calcium gluconate.

3. The preparation method of the calcium-alumino-silicate-hydrate nano-seeds suspension according to claim 1 , wherein the aqueous solution of silicon source is one or more of sodium fluorosilicate, magnesium fluorosilicate, sodium silicate, sodium metasilicate and potassium silicate.

4. The preparation method of the calcium-alumino-silicate-hydrate nano-seeds suspension according to claim 1 , wherein the aqueous solution of aluminum source is one or more of aluminum nitrate, sodium aluminate and aluminum hydroxide.

5. The preparation method of the calcium-alumino-silicate-hydrate nano-seeds suspension according to claim 1 , wherein a mass fraction of the solution of polycarboxylate superplasticizer is 2˜10 wt %.

6. The preparation method of the calcium-alumino-silicate-hydrate nano-seeds suspension according to claim 5 , in the calcium-alumino-silicate-hydrate nano-seeds suspension, the molar concentration of the silicon source is 0.05˜0.5 mol/L, the molar concentration of the calcium source is 0.05˜0.5 mol/L, the molar concentration of the aluminum source is 0.003˜0.03 mol/L, and a mass fraction of the solution of polycarboxylate superplasticizer is 0.8˜5%.

7. The preparation method of the calcium-alumino-silicate-hydrate nano-seeds suspension according to claim 1 , before adding the aqueous solution of calcium source, the aqueous solution of silicon source and the aqueous solution of aluminum source to the solution of polycarboxylate superplasticizer, it also includes:
pre-heating or pre-cooling the aqueous solution of calcium source, the aqueous solution of silicon source, the aqueous solution of aluminum source and the solution of polycarboxylate superplasticizer.

8. The preparation method of the calcium-alumino-silicate-hydrate nano-seeds suspension according to claim 1 , wherein the aqueous solution of calcium source, the aqueous solution of silicon source and the aqueous solution of aluminum source are simultaneously dropwise added to the solution of polycarboxylate superplasticizer with a speed of 0.2˜5 mL/min.

Assignees

• Univ Wuhan Tech

Inventors

• Wang Fazhou
• Hu Chuanlin
• Zou Fubing
• Hu Shuguang
• Zhang Mai

Classifications

• C01B33/26 Primary

  Aluminium-containing silicates {, i.e. silico-aluminates} · CPC title

• C04B22/0093

  Aluminates · CPC title

• C04B22/00863

  Calcium silicate hydrate · CPC title

• C01P2002/86

  by NMR- or ESR-data · CPC title

• C01P2004/04

  obtained by TEM, STEM, STM or AFM · CPC title