| In the present dissertation, a system of supported liquid membrane has been selected: D2EHPA used as carrier; decanol, kerosene and hexylmethane respectively used as the diluents; and polypropylene as membrane support material. The mechanism of ammonia (ammonium) transporting through the SLM and the factors affecting the permeability coefficient are investigated. At last, model of mass transfer across the supported liquid membrane is established, by which the mass transfer is simulated. Firstly, allocation coefficient, diffusion coefficient and reversible reaction equilibrium const are determined, and the operation factors affecting these parameters also investigated. The results obtained show that Kp value increases with the increasing of the initial concentration and pH value of the feed phase, using hexylmethane as diluent has higher Kp value than decanal and kerosene; the determined diffusion coefficients show little difference with the values that are calculated by the experiential equation given by Reid-Sherwood and Wilke-Chang; Kr increases as the carrier concentration increases, using hexylmethane as dilute has larger Kr value than the other two, Kr value increases with the decreasing of pH value in the feed phase, and is varied with pH value sharply.Secondly, relatively more ideal condition is investigated under which the total transport resistance is independent of the feed and strip resistance, that is, the main resistance is concentrated in the membrane. Under these conditions, the permeation process in the flat-sheet-supported liquid membrane is investigated, the model of the transport of NH3-N in membrane is established, and the parameters of the model are solved. The results show that when the stirring speed reaches 800 rpm, the total transport resistance is independent of the feed resistance; when there is no carrier in the membrane, or there is some proportion of carrier in the membrane, if the pH value is less than 2 or 3 respectively, the total transport resistance is independent of the strip resistance. Lastly, the factors affecting slope k such as the type of solvent, proportion of D2EHPA in the membrane, pH value of the feed and the strip, and the feed speed, are investigated. The model of the transport of NH3-N through hollow fiber liquid membrane is established. Using this model, the effects of the geometry dimension and property parameters of membrane support material and operation conditions on mass transport are analyzed. The results show that the model is consistent to the experiment date.The present research provide the theoretic guidance and foundation for the selection of SLM system and the optical of operation condition, and it lay some foundation for the practical application of the removal of ammonia nitrogen from waste water using SLM technology.
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