A novel membrane on pervaporation performance for dehydration of Caprolactam solution

Konjac glucomannan (KGM) is a kind of polysaccharide with wide applications, except in pervaporation (PV). This article focuses on the new function of KGM and simultaneously improving a new dehydration process for ɛ-Caprolactam (CPL). KGM was cross-linked with glutaraldehyde (GA) at proportions of 0.3, 0.5, and 0.7 wt%. Cross-linked membranes were characterized by scanning electron microscope, Fourier transform-infrared, and X-ray diffraction to assess the membranes of morphology, intermolecular interactions, and observe the effects of cross-linking on crystallinity, respectively. Cross-linked KGM as the active layer of the composite membranes has the net matrix structure, and many characteristics improved compared with pure KGM. Data showed that KGM cross-linked with GA displayed good swelling and PV performance, and the composite membranes had superior separation performances in dehydrating the CPL solution. The highest separation factor could reach 3531. The study provided a new way for both KGM application and CPL dehydration.