Green preparation method for hydroxyl oxime acid rare-earth flotation agents

The invention provides a green preparation method for hydroxyl oxime acid rare-earth flotation agents. The green preparation method comprises the steps of fatty acid esterification, fatty acid ester oximation and acidification. After the fatty acid esterification and before the fatty acid ester oximation, waste liquid is not treated, and a fatty acid esterification mixed product is totally added into a reaction kettle for performing oximation directly. The invention also provides another green preparation method for the hydroxyl oxime acid rare-earth flotation agents. The green preparation method comprises the steps of fatty acid esterification, fatty acid ester separation and purification, fatty acid ester oximation and acidification; when the step of fatty acid ester acidification is performed, the waste liquid obtained by separating and purifying the fatty acid ester is added. A hydroxyl oxime acid rare-earth collecting agent is synthesized by adopting the process provided by the invention, the waste water discharge during a synthesizing process can be reduced; the green preparation of the hydroxyl oxime acid rare-earth flotation agents can be realized; the economic benefit of an enterprise can be greatly improved; meanwhile, the flotation agents obtained by the method provided by the invention have excellent flotation performance.