Patent ID: 8974696
Filing Date: 2015-03-10
Classification: C01B,C01G,C01P,C09K

Abstract:
1. A method for preparing a complex fluoride having the formula (1): wherein M is at least one tetravalent element selected from the group consisting of Si, Ti, Hf, Ge, and Sn, A is at least one alkali metal selected from the group consisting of Li, Na, K, Rb, and Cs, said method comprising the steps of: providing a first solution containing a fluoride of tetravalent element M, hydrogenfluoride, and water, providing a second solution containing a compound of alkali metal A and/or the compound of alkali metal A in solid form, the compound of alkali metal A being selected from the group consisting of a fluoride, hydrogenfluoride, nitrate, sulfate, hydrogensulfate, carbonate, hydrogencarbonate, and hydroxide, mixing the first solution with the second solution and/or the solid for reacting the fluoride of tetravalent element M with the compound of alkali metal A to form a solid product, and recovering the solid product via solid-liquid separation.