In-situ incorporation of halloysite nanotubes with 2D zeolitic imidazolate framework-L based membrane for dye/salt separation

Layered assembled membranes of 2D leaf-like zeolitic imidazolate frameworks (ZIF-L) nanosheets have received great attention in the field of water treatment due to the porous structure and excellent antibac-terial ability, but the dense accumulation on the membrane surface and the low permeate flux greatly hinder their application. Herein, we synthesized mHNTs (modified halloysite nanotubes)/ZIF-L nanocom-posites on modified mHNTs by in situ growth method. Interestingly, due to the different size of mHNTs and ZIF-L, mHNTs were packed in ZIF-L nanosheets. The hollow mHNTs provided additional transport channels for water molecules, and the accumulation of the ZIF-L nanosheets was decreased after assem-bling mHNTs/ZIF-L nanocomposites into membrane by filtration. The prepared mHNTs/ZIF-L membrane presented high permeate flux (59.6 L center dot m-2 center dot h-1), which is 2-4 times of the ZIF-L membranes (14.8 L center dot m-2 center dot h-1). Moreover, mHNTs/ZIF-L membranes are intrinsically antimicrobial, which exhibit extre-mely high bacterial resistance. We provide a controllable strategy to improve 2D ZIF-L assembles, and develops novel membranes using 2D package structure as building units.(c) 2022 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.