Method of preparing zinc-containing material, method of preparing electrogalvanizing bath, and method of producing electrogalvanized steel sheet

A method of preparing a zinc-containing material, the method comprising:

• a zinc leaching step of bringing steelmaking dust into contact with an acidic aqueous solution to leach zinc contained in the steelmaking dust into the acidic aqueous solution;
• a first impurity precipitation step of precipitating impurities while a pH of a first treatment solution obtained in the zinc leaching step is 4.0 or more and 6.0 or less;
• a second impurity precipitation step of adding 0.10 g/L or more of a chelating agent to a second treatment solution, obtained in the first impurity precipitation step, while a pH of the second treatment solution is 4.0 or more and 6.0 or less to precipitate impurities;
• a first solid-liquid separation step of subjecting a third treatment solution, obtained in the second impurity precipitation step, to solid-liquid separation;
• a zinc precipitation step of precipitating a zinc-containing material while a pH of a fourth treatment solution obtained in the first solid-liquid separation step is 8.0 or more and 12.0 or less;
• and
• a second solid-liquid separation step of separating a fifth treatment solution obtained in the zinc precipitation step into a zinc-containing material and residual liquid.