Method of making barium titanate
View Patent ↗The present invention provides a method of making barium titanate powder. The method includes adding barium acetate to a solution of oxalic acid and titanium oxychloride to form barium titanyl oxalate and then calcining the barium titanyl oxalate to obtain barium titanate powder.
1. A method of making barium titanate powder comprising:
adding barium acetate to a solution comprising oxalic acid and titanium oxychloride to form barium titanyl oxalate; and
calcining the barium titanyl oxalate to obtain barium titanate powder.
2. The method according to claim 1 wherein the barium titanyl oxalate is recovered as a precipitate from the solution prior to calcination.
3. The method according to claim 2 wherein the precipitate is washed with deionized water prior to calcination.
4. The method according to claim 2 wherein the barium titanyl oxalate is recovered by filtration prior to calcination.
5. The method according to claim 2 wherein the barium titanyl oxalate precipitate has an average particle size of from about 4 μm to about 6 μm prior to calcination.
6. The method according to claim 1 wherein the solution of oxalic acid and titanium oxychloride comprises an aqueous solution.
7. The method according to claim 6 wherein the aqueous solution is formed using deionized water.
8. The method according to claim 7 wherein the molar ratio of oxalic acid to titanium oxychloride is from about 2.0 to about 2.5.
9. The method according to claim 7 wherein the molar ratio of barium acetate to titanium oxychloride is from about 1.0 to about 1.3.
10. The method according to claim 1 wherein the barium acetate is added to the solution when the solution is at a temperature of from about 10° C. to about 30° C.
11. The method according to claim 1 wherein the barium acetate is added to the solution when the solution is at a temperature of from about 20° C. to about 25° C.
12. The method according to claim 1 wherein the barium titanyl oxalate is calcined at a temperature of from about 800° C. to about 1250° C. for a period of from about 1 hour to about 8 hours.
13. The method according to claim 1 wherein after calcination the barium titanate powder is comminuted to display an average particle size within the range of from about 0.3 to about 0.5 microns.
14. A method of making barium titanate powder comprising:
adding barium hydroxide to a solution comprising oxalic acid and titanium oxychloride to form barium titanyl oxalate; and
calcining the barium titanyl oxalate to obtain barium titanate powder.