Liquid/Liquid Interface Properties In Centrifugal Separation And Theoretical Study On Adsorption Dynamics Of Nanoparticles

The refining processes of caprolactam always produce a lot of the residual solution called distilled residual solutions of benzene which contains20-50%caprolactam ingredients. In order to recycle caprolactam, reduce the pressure of environment and save resources, centrifugal extraction technology is used to recycle caprolactam. The recycle processes have two problems. On the one hand, the pollutants at the nanoscale can cause noticeable impact on the oil-water interfacial structure, and then they can affect the oil-water mass transfer efficiency. On the other hand, in order to separate the nanoscale contaminants, we need to add the chelating particles to absorb the contaminants. It is very important to investigate two parts of caprolactam recycle.For the first part, molecular dynamic simulation (MD) is performed to investigate the effect of nanoparticle on the liquid/liquid interface. The result shows that the nanoparticle which far away from the interface has little effect on the interface; the nanoparticle nearly to the interface can decrease the interfacial tension, A reduction of the interfacial tension is beneficial for two contact phases for higher transport processes. The larger particle has greater effect on the interface.For the second part, the effects of shear flow on adsorptions are investigated. Rotational speed only strengthens adsorption. Besides, the capture time of contaminant particles is dominated by the diffusion process of contaminant particles in the solvent. Towards which we derived a simple equation for estimating capture time.Our theoretical studies provide guidance for improving the efficiency of extraction of caprolactam and separating contaminants.