Tannin amide beneficiation aid as well as preparation method and application thereof

The invention discloses a tannin amide beneficiation auxiliary agent and a preparation method and application thereof.The tannin amide beneficiation auxiliary agent is prepared by taking tannic acid and an alcohol amine compound as raw materials to conduct an amino acid condensation reaction, the tannin amide beneficiation auxiliary agent has the dual effects of grinding aiding and selective inhibition, the mineral grinding efficiency can be improved, and the mineral processing efficiency can be improved. And meanwhile, efficient separation of various sulphide ores can be achieved, the comprehensive recycling rate is increased, the flotation index is optimized, and the comprehensive cost of ore grinding and ore dressing can be reduced. The preparation method of the mineral separation additive is simple, raw materials are easy to obtain, cost is low, reaction conditions are mild, no by-product is generated, environment friendliness is achieved, and industrialization is easy to achieve; meanwhile, tannic acid s