Building brick comprising a porous material, the microstructure of which is controlled by the addition of a nucleating agent during the process of preparing same

Patent metadata

Field	Value
Publication number	US-9212096-B2
Application number	US-201214382772-A
Country	US
Kind code	B2
Filing date	Dec 12, 2012
Priority date	Mar 5, 2012
Publication date	Dec 15, 2015
Grant date	Dec 15, 2015

Abstract

A building brick with cellular structure comprising a porous material, said porous material being obtained by a process comprising the following successive steps:
a step a) of synthesis of quicklime; a step b) of mixing said quicklime, water and silica; a step c) of introduction of a nucleating agent; a step d) of hydrothermal synthesis to obtain a ceramic mass, and a step e) of drying said ceramic mass obtained in step d).

First claim

The invention claimed is:

1. A building brick with cellular structure comprising a secondary material, said secondary material being obtained by a process comprising the following successive steps:
a) synthesizing quicklime, by calcination at a temperature greater than or equal to 800° C. of limestone blocks of average size between 1 mm and 15 mm having a purity of at least 90 wt % and an open porosity above 0% to less than or equal to 25%, to obtain particles of quicklime;
b) mixing said quicklime obtained in step a) with water and silica, in a CaO/SiO 2 molar ratio between 0.5 and 3 to obtain a cream of said constituents;
c) introducing a nucleating agent into the cream prepared in step b);
d) heating said cream obtained from step c) at a saturated water vapor pressure between 2.10 5 Pa and 20.10 5 Pa and at a temperature between 130° C. and 200° C. for a time between 15 hours and 30 hours, to obtain a ceramic mass; and
e) drying said ceramic mass obtained in step d) at a temperature between 100° C. and 400° C. for a time between 5 and 24 hours,
wherein the production process comprises a step c1) in the course of which some or all of the cells of at least one building brick with cellular structure are partially or completely filled with said cream prepared in step c), and in that said building brick with cellular structure, after undergoing said step c1), is then submitted to steps d) and e).

2. The building brick as claimed in claim 1 , wherein said building brick is wetted beforehand with water before carrying out step c1).

3. The building brick as claimed in claim 1 , wherein all the cells of said building brick with cellular structure are filled to at least 50% of their internal volume with said cream prepared in step c).

4. The building brick as claimed in claim 1 , wherein in step c), from 0.01 to 10 wt % of nucleating agent is introduced into the cream prepared in step b), preferably from 1% to 5%.

5. The building brick as claimed in claim 1 , wherein the nucleating agent is selected from the group consisting of lime, silica, and combinations thereof.

6. The building brick as claimed in claim 5 , wherein the nucleating agent is in nanometric form.

7. The building brick as claimed in claim 5 , wherein the nucleating agent is in the form of colloidal suspension.

8. The building brick as claimed in claim 5 , wherein the nucleating agent is in the form of a powder with granulometry between 50 nm and 2 μm.

9. The building brick as claimed in claim 1 , wherein the nucleating agent is a powder with granulometry between 50 nm and 5 μm or a colloidal suspension selected from the group consisting of one of the following crystalline phases: gyrolite, tobermorite, xonotlite, foshagite, jennite, afwillite, hillebrandite and combinations thereof.

10. The building brick as claimed in claim 1 , wherein the nucleating agent is a powder or a suspension of oxide of magnesium, of aluminum, of barium, of iron, of sodium, of titanium or a zeolite.

11. The building brick as claimed in claim 1 , wherein said building brick with cellular structure is a fired clay brick.

Assignees

• Air Liquide
• L Air Liquide Société Anonyme Pour L Etude Et L Expl Des Procédés Georges Claude

Inventors

• Del-Gallo Pascal
• Richet Nicolas
• Goudalle Sebastien

Classifications

• C04B14/303

  Alumina · CPC title

• C04B22/062

  of the alkali or alkaline-earth metals · CPC title

• C04B2/10

  Preheating, burning calcining or cooling (decarbonation during burning of cement raw materials C04B7/43; {obtaining CaO or MgO otherwise than by thermal decomposition of the corresponding carbonates C01F11/02, C01F5/02}) · CPC title

• C04B14/30

  Oxides other than silica {(ferrites C04B14/363)} · CPC title

• C04B14/305

  Titanium oxide, e.g. titanates · CPC title