US 12,139,411 B2
Hydrolytic and calcination method for forming hollow silica particles
Ayhan Bozkurt, Dammam (SA); Seyda Tugba Gunday Anil, Dammam (SA); Munirah Abdullah Almessiere, Dammam (SA); and Sultan Akhtar, Dammam (SA)
Assigned to Imam Abdulrahman Bin Faisal University, Dammam (SA)
Filed by Imam Abdulrahman Bin Faisal University, Dammam (SA)
Filed on May 10, 2024, as Appl. No. 18/660,358.
Application 18/660,358 is a continuation of application No. 17/237,261, filed on Apr. 22, 2021, granted, now 12,017,922.
Application 17/237,261 is a continuation of application No. 15/995,904, filed on Jun. 1, 2018, granted, now 11,242,256, issued on Feb. 8, 2022.
Prior Publication US 2024/0294387 A1, Sep. 5, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. C01B 33/18 (2006.01); C01B 33/12 (2006.01)
CPC C01B 33/18 (2013.01) [C01B 33/124 (2013.01); C01P 2004/34 (2013.01); C01P 2004/88 (2013.01); C01P 2006/12 (2013.01); C01P 2006/14 (2013.01); C01P 2006/16 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A hydrolytic and calcination method for forming hollow silica spheres, the method comprising:
dissolving a trialkoxy (aryl) silane in an aqueous solution comprising water and a mineral acid to form a hydrolyzed silane solution;
mixing the hydrolyzed silane solution with a hydroxide base to form a precipitate in a suspension;
centrifuging the suspension to separate the precipitate from the suspension; then
washing the precipitate with an organic solvent and water; then
calcining the precipitate to form hollow silica spheres, wherein the calcining is performed by
heating to a first temperature of 180 to 240° C. with a first ramp rate of 3 to 10° C./min and holding the first temperature for 2 minutes to 2 hours, then
heating to a second temperature of 600 to 740° C. at a second ramp rate of 0.1 to 4° C./min, and holding the second temperature for 2 to 24 hours,
wherein a template is not employed for forming the hollow silica spheres.