| Wide variety of sources and increasingly serious heavy metal pollution is a major threat to the ecological environment security and safety of drinking water. Supported liquid membrane separation processes have been recently receiving considerable attention due to characteristics such as the fast mass transfer, high selectivity and separation efficiency, lower operation costs and no secondary pollution. And they are particularly suitable for the separation and enrichment of heavy metal ions. However, supported liquid membrane separation processes can be limited in a large-scale industrial applications due to membrane instability and shortly membrane life.In this paper, dispersion supported liquid membrane (DSLM)separation processes, a new liquid membrane separation system,can be advanced based on the theoretical study of the existing supported liquid membrane(SLM) separation technology. The transport behavior of conventional divalent heavy metal ions and the noble metal ions have been studied in this thesis. The stability problem of SLM have been solved. A new separation method of mixed metal ion separation and recovery is obtained. The mathematical model of heavy metal ions transport through DSLM is established by the analysis of mass transfer. The results are sumrnarized as follows:1. The transport behavior of conventional divalent heavy metal ions including Co(Ⅱ), Zn(Ⅱ), Cd (Ⅱ), Cu (Ⅱ) and Pb(Ⅱ) through DSLM with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (commercially known as PC-88A) as mobile carrier and kerosene as a membrane solvent was studied. Various factors affecting heavy metal ions transfer were discussed. The optimum conditions of transport are summarized as follows:feed solution pH 6.00,4.00,5.00,5.25 and 5.25 respectively; the volume ratio of liquid membrane to stripping solution 160:40; HCl concentrations in stripping solution 4.00 mol-L-1,4.00mol·L-1, 400mol·L-1,4.00mol·L-1 and 5.OOmol-L"1 respectively. Under the optimum transport conditions, the transport rate can reach 94.4%(in 190min),90.0%(in 190min),82.7% (in 190min),90.0%(in 130min) and 88.9%(in 190min) respectively. We can see that DSLM has a high transmission efficiency in comparison with conventional SLM. At the same time the system can improve the stability of the membrane and extend the life of the membrane.2. The transport behavior and rules of noble metal ions including Ag(I), Au(III), Pt(IV) and Pd(II) through DSLM with appropriate mobile carrier were studied. Various factors affecting noble metal ions transfer were discussed. The optimal conditions of transport are summarized as follows:mobile carrier tri-n-octylamine, tri-n-octylamine, PC-88A, N503 respectively; medium in feed solution 0.20mol·L-1 HNO3and 0.10 mol·L-1 KSCN,2.00mol·L-1 HCl, 0.50mol·L-1 HCl,0.10 mol·L"1 HCl respectively; the volume ratio of liquid membrane to stripping solution 40:20,40:20,140:60 and 30:30 respectively; stripping solution 0.125mol·L-1Na2S2O3, 0.33mol·L-1KCN, 7.00mol·L-1HCl and 1.60mol-L-1KSCN respectively. Under the optimum transport conditions, the transport rate can reach 80.0%,100.0%,100.0% and 79.8% respectively during the transport time of 130min. We can see that DSLM has a high transmission efficiency in comparison with conventional SLM.3. The transport kinetics equation of heavy metal ions through DSLM is derived based on the transfer process analysis. The transport kinetics parameters do andδa are calculated through the DSLM.The calculated results are in good agreement with experimental results.4. Through the DSLM the selective separation of mixed heavy metal ions,such as Zn(II) and Cu(II), Zn(II) and Co(II), Cu(II) and Co(II), Pt(IV) and Co(II), Pt(IV) and Cu(II), Au(III) and Ag(I), Zn(II) and Cu(II) and Co(II), are explored. The results showed the mixed ions can be separated effectively through the DSLM.
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