	US 11,939,262 B2
	Method for manufacturing coal-based geopolymer foam including silica fume
Keeyun Lee, Seoul (KR); Hyo Kim, Namyangju-si (KR); and Jihoi Heo, Seoul (KR)
Assigned to HEUNGKUK IND.CO., LTD., Hanam-si (KR)
Appl. No. 17/548,429
Filed by HEUNGKUK IND.CO., LTD., Hanam-si (KR)
PCT Filed Mar. 25, 2021, PCT No. PCT/KR2021/003741 § 371(c)(1), (2) Date Jun. 23, 2022, PCT Pub. No. WO2022/181871, PCT Pub. Date Sep. 1, 2022.
Claims priority of application No. 10-2021-0025041 (KR), filed on Feb. 24, 2021.
Prior Publication US 2023/0202923 A1, Jun. 29, 2023
Int. Cl. C04B 18/08 (2006.01); C04B 7/24 (2006.01); C04B 7/28 (2006.01); C04B 12/00 (2006.01); C04B 18/14 (2006.01); C04B 20/02 (2006.01); C04B 22/06 (2006.01); C04B 28/00 (2006.01); C04B 38/10 (2006.01); C04B 41/00 (2006.01); C04B 28/26 (2006.01); C04B 38/02 (2006.01); C04B 103/10 (2006.01); C04B 111/40 (2006.01)

CPC C04B 12/005 (2013.01) [C04B 7/243 (2013.01); C04B 7/28 (2013.01); C04B 18/08 (2013.01); C04B 18/141 (2013.01); C04B 18/146 (2013.01); C04B 20/026 (2013.01); C04B 22/064 (2013.01); C04B 28/006 (2013.01); C04B 38/10 (2013.01); C04B 41/0072 (2013.01); C04B 28/26 (2013.01); C04B 38/02 (2013.01); C04B 2103/10 (2013.01); C04B 2111/40 (2013.01); Y02P 40/10 (2015.11); Y02W 30/91 (2015.05)]

5 Claims

1. A method for manufacturing geopolymer foam with coal ash, the method comprising the steps of:

(1) mixing water glass (Na₂SiO₃) and sodium hydroxide (NaOH) to prepare an alkali activator;

(2) adding silica fume as blowing agent to the alkali activator and stirring the same;

(3) pulverizing coal bottom ash;

(4) mixing the coal bottom ash with coal fly ash to prepare coal ash;

(5) adding the mixture of silica fume and the alkali activator to the coal ash and then further adding the alkali activator to adjust a ratio of alkali activator/solid material comprising the coal ash and the silica fume, followed by mixing the same;

(6) loading and sealing the mixture in a mold to prepare a specimen;

(7) curing the specimen in an oven; and

(8) exposing to a temperature of as high as 200° C. to 600° C. for 2 hours the specimen that has completely undergone the curing,

wherein the coal fly ash is contained in an amount of 10 to 50% by weight based on the total weight of the coal bottom ash and the coal fly ash in step (4),

wherein the ratio of alkali activator/the solid material comprising the coal ash and the silica fume ranges from 0.38 to 0.50 in step (5).