A study on the membrane coalescence demulsification was carried out with four working systems of water/n-butyl alcohol, water/n-octanol, water/30% TBP(in kerosene) and water/kerosene. The membranes made of polytetrafluoroethylene (PTFE) with 1.0μm pore size were used. The results indicated that the excellent demulsification efficiency for emulsions with various oil contents was obtained. A conductivity probe was used to study the demulsification mechanism. An electrode probe was designed and used to determine the oil content near the membrane surface. The obtained data showed that the oil content in the permeated stream was much higher than that in the feed emulsion. A physical mechanism to explain the membrane demulsification was put forward.
Membrane dispersion extraction is a process with a macroporous membrane as dispersion medium. In this paper, 30%TBP(in kerosene)/nitric acid/H 2O is chosen as an experimental system. The mass transfer characteristics are studied in two kinds of membrane dispersion modules.In order to improve mass transfer performance, a concentric inner element is designed. The effects of transmembrane pressure and the flux of continuous phase on efficiency, as well as on the flux of dispersion phase are investigated. The experimental results show that the flux of disperse phase is increased with an increase of the transmembrane pressure. However, it could hardly be influenced by the flux of continuous phase. mass transfer efficiency decreases slightly when the pressure or the flux of continuous phase is increased. The concentric inner element can improve the mass transfer performance greatly. Membrane dispersion extraction can be carried out with a higher mass transfer efficiency.
