Nanofiltration membrane, preparation method and dye separation method

Abstract

According to the invention, an electrospun nanofiber membrane is selected as a base membrane; meanwhile, through a simple doped cross-linking method, polyethyleneimine is introduced into a transitionlayer; and amine functional groups exposed in fiber exert great effects in the process of interfacial polymerization. Thus, the overall separation performance of a membrane is improved; meanwhile, a prepared membrane has good stability and good rejection effect on a dye; when a test pressure is 2 bar, the rejection rate of the membrane is 90% or above; and the prepared membrane has good pure waterflux which is in a range of 34.5 to 42.5 L m<-2>h<-1>bar<-1>. When the range of a pressure is in a range of 1 and 5 bar, the rejection performance of a composite membrane is basically unchanged, andthe flux and pressure are basically in a linear relationship, so a low-pressure nanofiltration membrane is prepared. In a stability test of 48 h, the composite membrane has good stability.

Description

technical field [0001] The invention relates to a nanofiltration membrane, a preparation method and a dye separation method, belonging to the technical field of membrane separation. Background technique [0002] The textile printing and dyeing industry typically consumes large amounts of water and is one of the most difficult sources of wastewater to treat, most of which are non-biodegradable, generally highly toxic, and may even be harmful to aquatic life. Therefore, more and more attention has been paid to the treatment of dye wastewater. Therefore, insufficient release of dyes from water into the environment not only pollutes domestic water resources, but also poses a great survival risk to humans, and also reduces light penetration, causing adverse effects on aquatic flora and fauna. Given these problems, many research efforts have attempted to efficiently remove dyes from wastewater. [0003] Commonly used treatment methods include physical treatment processes such ...

AI Technical Summary

Problems solved by technology

[0010] The technical problem to be solved by the present invention is: when using traditional phase inversion membrane as the base membrane to prepare loose nanofiltration membrane, the prepared nanofiltration membrane has high molecular weight cut-off, low flux and low membrane strength.

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