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Precious metals has unique physical and chemical properties gradually by people of all ages, has been widely used in various fields. However, due to the physical and chemical properties of noble metals are very similar, and the valence changing, the difference between the different valence states, precious metals separation has been a problem. Liquid membrane separation technology integrates extraction and back extraction in one, with a high mass transfer rate and flux, high selectivity, good separation efficiency and concentration factor, as well as simple operation, in recent years the more widely studied novel separation technology. In order to improve the selectivity of precious metals separation and practicality, many researchers film technique is applied to the separation of precious metals, has made good progress. However, studies have reported more emulsion liquid membrane, supported liquid membrane (SLM) separation of precious metals research reported less. This article choose precious metals platinum and palladium as separate objects, solvent extraction experiments based on a systematic study of Pt (Ⅳ) and Pd (II) of the supported liquid membrane migration of the following results: 1, Pt (Ⅳ the different extractant) and Pd (II) of the extraction equilibrium, respectively, of the Pt (Ⅳ) and Pd (Ⅱ) extraction and back extraction conditions, the optimal experimental conditions. (1) Pt (IV) of the extraction equilibrium experiments in the initial concentration of the Pt (Ⅳ) a 5.0μg/mL water phase when the stannous chloride concentration of 0.05 mol / L, hydrochloric acid concentration of 0.50mol / L, organic kerosene as diluent extractant 2 - ethylhexyl phosphonic acid - mono-2 - ethylhexyl acrylate (P 507 ) and a concentration of 5.0% (w / v), the aqueous phase and the organic phase selection phase volume ratio is 1:1, the oscillation 30min Pt (IV) extraction rate of up to 100%. Select volume 4mol / L hydrochloric acid as the stripping agent, the stripping rate of 99% or more. (2) Pd (II) of the extraction equilibrium experiments in the Pd (II) initial concentration of a 6.754μg/mL the aqueous phase, when the concentration of hydrochloric acid 0.10mol / L, the organic phase selection kerosene as a diluent, extractant N -heptyl, N-dimethyl acetamide (N 503 ) concentration of 10.0% (w / V), and the aqueous phase and the organic phase volume ratio of 1:1, the oscillation 30min, Pd (II) of the The extraction rate of 99.2%. Choose an equal volume of 0.2 mol / L potassium thiocyanate solution as a stripping agent, stripping more than 95%. Supported liquid membrane separation experiments hydrophobic porous polyvinylidene fluoride membrane support in the P 507 and N 503 as mobile carrier, kerosene as the membrane solvent, respectively, research migration of the Pt (Ⅳ) and Pd (Ⅱ) supported liquid membrane. (1) Pt (Ⅳ) migration experiment Pt (Ⅳ) initial concentration 1.0μg/mL, the effects of the feed phase concentration of hydrochloric acid, stannous chloride concentration, carrier concentration, stripping the relative concentration of hydrochloric acid and other factors on the Pt (Ⅳ) the impact of migration, to determine the best migration conditions for Pt (Ⅳ): Pt (Ⅳ) concentration in the feed phase 1.0μg/mL hydrochloric acid concentration of 1.0 mol / L, stannous chloride concentration of 0.05mol / L, and the membrane phase P 507 concentration of 5.0% (w / V), and the stripping phase hydrochloride concentration of 6.0mol / L, migration 3h, Pt (IV) mobility up to 100%. (2) of Pd (II) the migration experiment Pt (Ⅳ) initial concentration 3.0μg/mL, effects of hydrochloric acid concentration of the feed phase, carrier concentration and stripping potassium thiocyanate concentration of Pd (Ⅱ) migration the impact, determine the Pd (Ⅱ) optimal migration conditions: feed phase Pd (II) concentration 3.0μg/mL the hydrochloric acid concentration 0.2mol / L, in the membrane phase N 503 concentration was 10.0% (w / V), the stripping phase potassium thiocyanate concentration of 0.2mol / L, migration 4H, Pd (II) of the migration rate of up to 93%. 3, simulation experiments based on research supported liquid membrane migration of Pt (Ⅳ), P 507 / kerosene supported liquid membrane system, Pt (Ⅳ) and part of the transition metal ion separation. Two metal ion separation experiments under the best migrate conditions of Pt (Ⅳ), 1.0μg/mL of Pt (Ⅳ) effective (1), respectively, from the 50μg/mL the Ni (II), of 100μg/mL the Co (II) of 100μg/mL the Cu (II), a 150μg/mL the Zn (Ⅱ) separation, migration 3h mobility of Pt (IV) were 89%, 86%, 81%, 87%, the basic Pt (Ⅳ) and Ni (II) and Pt (IV) and Co (II), Pt (IV) and Cu (II) and Pt (IV) and Zn (Ⅱ) separated from each other. (2) preparation of simulated electroplating waste separation experimental simulation of a workshop plated platinum wastewater, its composition for Pt (Ⅳ) (0.8μg/mL), Cu (Ⅱ) (75μg/mL), Zn (Ⅱ) (75μg / mL), Co (Ⅱ) (75μg/mL), Ni (Ⅱ) (75μg/mL), SO 4 2 - (75μg/mL). Pt (Ⅳ) under the conditions of migration, migration 3h, the migration rate of 87.8%, and none of the other ions migrate, Pt (Ⅳ) established SLM separation method has certain application reference value.
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