3results about How to "Achieve selective separation" patented technology

The application provides a method for selectively recovering metal elements in waste batteries by using a functional deep eutectic solvent, which comprises the following steps: mixing choline chloride, phosphoric acid and a choline hydroxide solution to obtain a deep eutectic solvent DES; pretreating a positive electrode of a waste lithium iron phosphate (LFP) battery and a waste lithium cobalt oxide (LCO) battery; and immersing the positive electrode in the deep eutectic solvent DES to make Li + enriched into the leaching solution, Fe is converted into FePO4 and left in the residue, and then cobalt is recovered by "ethanol-induced precipitation", lithium is recovered by "pH-controlled precipitation", and the DES is regenerated. 2+ This method realizes the closed loop of lithium iron phosphate and lithium cobalt oxide battery recycling in a green and economic way through the strategies of segmented targeted leaching and selective coordination precipitation, combined with solvent regeneration.

The application discloses a method for recovering propylene glycol methyl ether and propylene glycol methyl ether acetate from waste diluent, belongs to the field of diluent recovery, and aims at the technical problems that the recovery purity, recovery rate and long-period operation stability of PM and PGMEA in waste diluent need to be further improved, and specifically comprises the following steps: after pretreatment, the waste diluent is transported to a fixed complex separation bed filled with non-halogen hydrogen bond acceptor complex materials, so that propylene glycol methyl ether and water are complexed with the non-halogen hydrogen bond acceptor complex materials and are retained, the non-halogen hydrogen bond acceptor complex materials are constructed, propylene glycol methyl ether acetate is preferentially flowed out, and three-stage vacuum pyrolysis complexing is performed to realize segmented release and material regeneration, so that the high-purity recovery of propylene glycol methyl ether or propylene glycol methyl ether acetate is ensured, and the high recovery rate and long-period operation stability are maintained.

The application belongs to the technical field of haematococcus pluvialis separation, and specifically discloses a ternary cross-linked nanofiltration membrane, a preparation method and application. The nanofiltration membrane comprises a polyethersulfone ultrafiltration membrane base film, a polydopamine intermediate layer and a ternary cross-linked functional layer sequentially loaded on the surface of the polyethersulfone ultrafiltration membrane base film. The preparation method comprises the following steps: preparing the polydopamine intermediate layer, anchoring oxidized haematococcus pluvialis polysaccharide, covalently cross-linking polyphenylated chitosan, coordination cross-linking iron ions, and post-treatment to obtain the ternary cross-linked nanofiltration membrane. The ternary cross-linked nanofiltration membrane is used for separating haematococcus pluvialis polysaccharide and astaxanthin ester. The ternary cross-linked functional layer simultaneously has three separation abilities of size screening, charge regulation and coordination selection, realizes selective separation of astaxanthin ester and neutral oil with similar molecular weights, and effectively retains macromolecular polysaccharide.