Copper-tin-nickel brazing material prepared by alloys recycled from E-waste, preparation method therefor and system thereof

A preparation method for a copper-tin-nickel brazing material using an alloy recycled from an E-waste, comprising following steps:

• (a) spreading nano-SiO2 on a bottom of a crucible and then adding a crude copper-tin-iron-nickel alloy recycled from the E-waste;
• (b) heating the crucible to melt the crude copper-tin-iron-nickel alloy into a metal liquid, so that a first impurity in the metal liquid reacts with the SiO2 at the bottom to form a slag that floats out and is removed, wherein the first impurity includes Zn and Pb;
• (c) introducing a refining gas to a bottom of the metal liquid in step (b) and stirring a resultant, such that a second impurity in the metal liquid forms a scum or a gas and then is removed, wherein the second impurity includes Pb, Fe, S, and O;
• (d) performing a heat-preserving directional solidification on the metal liquid in step (c), so as to bias-aggregate a third impurity at one end and remove the third impurity to obtain a copper-based intermediate alloy, wherein the third impurity includes Fe and Sb;
• and
• (e) smelting and powdering the copper-based intermediate alloy in step (d).