Method of producing stannous oxide, stannous oxide, method of Sn plating solution, and method of removing impurities from Sn plating solution

摘要

The method of producing stannous oxide includes: a Sn ion-containing acid solution forming step (S01); a first neutralizing step (S02), which is a step of forming Sn precipitates by adding one or more of alkaline solutions of ammonium carbonate, ammonium bicarbonate, and aqueous ammonia to the Sn ion-containing acid solution to retain pH at 3-6 therein; a Sn precipitate separating step (S03); a Sn precipitate dispersing step (S04), which is a step of dispersing the separated Sn precipitates in a solvent liquid to obtain a dispersion liquid; and a second neutralizing step (S06), which is a step of forming SnO by adding an alkaline solution to the dispersion liquid of the Sn precipitates and then by heating, wherein Na, K, Pb, Fe, Ni, Cu, Zn, Al, Mg, Ca, Cr, Mn, Co, In, and Cd reside in the Sn ion-containing acid solution in the first neutralizing step (S02).