| As an important industrial material, the paranitrophenol (PNP) is widely used in dyestuff, medicine and chemosynthesis plant. However, it's toxic, hard to be decomposed and can be enriched in the organism. So the innocent treatment of phenolic wastewater means much to the environment. Supported liquid membrane (SLM) has advantages of simple operating and effective separating. Transport of PNP through supported liquid membrane containing N,N' -di(1-methyl-pentyl)acetamide (N-503) and tricotylamine (TOA) as the mobile carrier, kerosene as the diluent and PVDF as the supporting material, was studied respectively in this paper. The effects of various parameters were investigated. The optimum experimental conditions were achieved by separation experiment, and the kinetics models were established. The conclusions are as follows:(1) In the N-503/kerosene SLM system, the optimum conditions to separate the PNP are: pH=1.42 in the feed phase, using KNO3 to adjust the ionic strength to be I=0.4, sodium hydroxide concentration in the stripping solution phase is 0.025mol/L, concentration of N-503 in the membrane phase is 20%, when initial PNP concentration in the feed solution phase is c0=1.8×10-4 mol/L, in 60min, the transfer rate can reach 82.5% and the permeability coefficient is P=3.58×10-3m/s.(2) In the TOA/kerosene SLM system, the optimum conditions to separate the PNP are: pH=1.3 in the feed phase, using KC1 to adjust the ionic strength to be I=0.4, potassium hydroxide concentration in the stripping solution phase is 0.0375mol/L, concentration of TOA in the membrane phase is 20%, when initial PNP concentration in the feed solution phase is c0=1.8×10-4 mol/L, in 60min, the transfer rate can reach 83.53% and the permeability coefficient is P=3.96×10-3m/s.(3) In the N-503/kerosene SLM system, the transport of PNP obeys the kinetic equation P=5.03×10-3cN-503/(1.513cN-503+1), the thickness of feed-membrane diffusion layer is daq=2.72×10-3m, and the diffusion coefficient in the membrane phase is Dorg=3.75×10-8m2/s. In the TOA/kerosene SLM system, the transport of PNP obeys the kinetic equation P=1.259×10-2cTOA/(3.402cTOA+1), the thickness of feed-membrane diffusion layer is daq=2.43×10-3m, and the diffusion coefficient in the membrane phase is Dorg=9.38×10-9m2/s.(4) The [H+]-P experience formulas in feed phase were obtained: P=1.598×10-3×(-lg[H+])-0.2302 in the...
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