Method separating silicon powder and silicon carbide powder by interface tension

The invention relates to a powder separation technology of silicon and silicon carbide in mortar generated in a silicon wafer wire saw technology in the solar photovoltaic field, in particular to a method for separating the silicon and the silicon carbide by adopting difference of interface tensions. The separation method comprises the following steps: treating agent is added in the mortar generated in the silicon wafer wire saw technology according to a weight portion percentage of 100-1000:100-1000,; the treating agent and the mortar are uniformly stirred and divided into three layers in a sedimentation way, and silicon powders at the upper layer and silicon carbide powders at the lower layer are respectively collected; and the middle is a liquid layer. The treating agent comprises a solvent, reactant and a surface modifier, wherein the solvent, the reactant and the surface modifier are mixed according to a certain proportion, the reactant is hydrochloride, hydrofluoric acid, sulfate and citric acid, the su