Hydrogen peroxide-phosphoric acid mixture, and preparation method and application thereof

The invention provides a hydrogen peroxide-phosphoric acid mixture, and a preparation method and an application thereof. The hydrogen peroxide-phosphoric acid mixture is composed of hydrogen peroxide, phosphoric acid and a stabilizer, a mass ratio of hydrogen peroxide to phosphoric acid is 20:1-50:1, and the stabilizer accounts for 0.1-0.5% of the weight of hydrogen peroxide. The application method of the hydrogen peroxide-phosphoric acid mixture in treatment of cyanogen-containing silvering wastewater comprises the following steps: 1, carrying out electrolyzing pretreatment on the cyanogen-containing silvering wastewater to remove Ag as possible; and 2, treating the pretreated cyanogen-containing silvering wastewater by using the hydrogen peroxide-phosphoric acid mixture. The hydrogen peroxide-phosphoric acid mixture can be used to treat medium and low concentration cyanogen-containing silvering wastewater, and can also be used to treat high concentration cyanogen-containing silvering wastewater. The hydrogen peroxide-phosphoric acid mixture avoids secondary pollution and guarantees the health and safety of operators in the treatment process of the cyanogen-containing silvering wastewater, and allows the precious metal silver to be recovered in the electrolyzing pretreatment process.