The present invention provides Li-containing slag which is obtained by melting a starting material such as waste lithium ion batteries that contain Li and Al, and which has a slag melting point that is effectively controlled to a specific temperature or less, while suppressing the addition amount of a flux, wherein Li is effectively concentrated by suppressing the amount of slag. The present invention provides Li-containing slag which is obtained by melting a starting material that contains waste lithium ion batteries which contain lithium (Li) and aluminum (Al), and which is characterized in that: relational expressions Al/Li<5 and (silicon (Si))/Li<0.7 are satisfied in terms of the mass ratio; and 30% by mass or less of Al, 6% by mass or more of Mn, 3% by mass to 20% by mass of Li and 0% by mass to 7% by mass of Si are contained therein.

A dezincing method is provided that can remove zinc by designing the heating temperature for a galvanized steel sheet in consideration of the oxidation of zinc. In a dezincing method for removing zinc from a galvanized steel sheet stored in a container, the temperature and the oxygen partial pressure inside the container satisfy relationships of expressions (1) to (3) below:

[00001]$\begin{array}{cc}T17.6\log \left(P_{O2}\right)+1031& \left(1\right)\end{array}$$\begin{array}{cc}700T1200& \left(2\right)\end{array}$$\begin{array}{cc}{P}_{O2}10.13.& \left(3\right)\end{array}$

In expressions (1) to (3), T is the temperature ( C.) inside the container, and P.sub.O2 is the oxygen partial pressure (kPa) inside the container.

A method for separating indium oxide and tin oxide from an ITO waste target by a vacuum method disclosed by the present disclosure, which relate to the field of resource recycling and utilization technology. The method Includes: take ITO waste target raw material, add indium to the ITO waste target raw material, heat and hold under vacuum conditions, then the Indium oxide is obtained by the volatilization of the suboxide of indium into the volatile, and the tin oxide is obtained by remaining of the tin oxide in the condensate. The present disclosure is based on the fact that indium oxide can generate volatile suboxide (In.sub.2O) when heated in indium melt, and the generated suboxide can evaporate to the condensation zone for condensation, thereby achieving the separation of indium oxide and tin oxide and achieving resource recovery and utilization of ITO waste target materials.

A manufacturing method can obtain Al-based particles. A particle-dispersed molten salt (an example of an Al base material), in which Al-based particles (liquid phase) are dispersed in molten salt, can be obtained by bringing Al-based foil into contact with molten salt. Through particle-dispersed molten salt, for example, Al-based powder (an example of Al base material) composed of Al-based particles (solid phase) can be efficiently or easily obtained. By classifying Al-based particle groups, Al-based powder with a desired particle size distribution can be obtained. The Al-based foil has a thickness of, for example, at most 0.5 mm, and even 0.1 mm. The Al-based foil is supplied to molten salt in the form of shredded foil pieces. This allows Al-based powder to be obtained with a particle size distribution including fine particles. It is preferred to use, for example, a mixed salt containing NaCl and KCl as molten salt.

A method for recycling zinc (Zn), wherein the method comprises the following steps: providing a feed composition; adding the feed composition to a rotary oven; heating the added feed composition for producing a first liquid molten metal phase and a first supernatant dross; adding aluminum (Al) to the first liquid molten metal phase, wherein a second supernatant dross and a second liquid molten metal phase are formed; adding at least one flux to the second liquid molten metal phase, followed by at least one segregation step in which the second liquid molten metal phase is removed from the rotary oven; casting the second liquid molten metal phase, or adding the removed second liquid molten metal phase to a casting furnace; casting the second liquid molten metal phase from the casting furnace; wherein the method further comprises the steps of: removing the second supernatant dross from the rotary oven; subjecting the removed second supernatant dross to at least one crushing step and at least one sorting step for separating at least one zinc fraction and at least one zinc oxide fraction from the second supernatant dross; and using the at least one zinc fraction for contributing to provide the feed composition.