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Fullerene (C60) was successfully grafted on cellulose following with the modification of cellulose by acid chlorination and subsequently azidation. The structures of modified cellulose made by sulfonation, acylating chlorination, Azidation, ionization and fullerenated were determined by infrared spectroscopy. The results show that the raw cellulose can obtain good dissolution property when the methyl imidazole-chloropropylene ionic liquid is used as the solvent system. The choice of intermediates has an important effect on the modification. The better grafting efficiency can be obtained with acyl chlorinated cellulose, and the reactivity and reactivity control of the azided chlorinated cellulose fibers are more easily to obtain. The azided chlorinated cellulose can be grafted by fullerene successfully. [ABSTRACT FROM PUBLISHER]

In this paper, the adsorption of copper ions on the prepared multilayer diazo resin-graphene oxide/polyacrylonitrile composite membranes was studied, and the adsorption capacity of GO modified polyacrylonitrile membranes to copper ions under different conditions was explored. The concentration of copper ion solution before and after adsorption was measured by inductively coupled plasma (ICP). The results showed that the adsorption capacity of GO modified polyacrylonitrile membrane to copper ion increased first and then reached adsorption equilibrium with the increase of adsorption time of copper ion. With the increase of initial concentration of copper ion and external temperature, the adsorption capacity of GO modified polyacrylonitrile membrane to copper ion followed. With the increase of solution's PH, the adsorption capacity of GO modified polyacrylonitrile membranes for copper ions first increased and then decreased. After several desorption/adsorption of the modified membranes which have reached the adsorption equilibrium, the membranes still have good adsorption capacity for copper ions, indicating that the membranes have excellent reuse performance. [ABSTRACT FROM AUTHOR]

In this paper, a multilayer diazo resin-graphene oxide/polyacrylonitrile composite membrane was prepared by layer-by-layer self-assembly and UV-induced modification of commercial polyacrylonitrile (PAN) hollow fiber membranes grafted with diazo resin (DR) and graphene oxide (GO). Scanning electron microscopy (SEM), infrared spectroscopy, contact angle, thermogravimetric analysis (TG), water flux and adsorption properties of heavy metals were studied. The results showed that diazo resin (DR) and graphene oxide (GO) were successfully grafted onto PAN membranes by layer-by-layer self-assembly. Carbonyl and carboxyl groups appeared on the surface of the modified PAN membranes; layer-by-layer self-assembly modification did not destroy the original morphology of PAN membranes, resulting in smaller pore size and higher surface roughness; hydrophilicity of the modified PAN-(DR-GO)3 membranes. The contact angle of pure water decreases from 87.8 degrees to 55.5 degrees, and the water flux increases from 733.30 g.m−1.h−1 to 1250.48 g.m−1.h−1. The thermo gravimetric curves of PAN films before and after modification did not change significantly, and the PAN films before and after modification had good thermal stability. The modified PAN membrane can achieve adsorption equilibrium in a relatively short time, and has good adsorption performance for heavy copper ions, with the adsorption rate as high as 92%. [ABSTRACT FROM AUTHOR]

PAN hollow fiber functional membrane with heavy metal ion adsorption capacity was prepared via layer-by-layer method using diazo-resin (DR). Ethylenediaminetetraacetic acid (EDTA) and graphene oxide (GO) with chelating function were used as modifier. Modification effect was studied by Fourier Transform Infrared Spectrometer (FTIR), contact angle test, scanning electron microscopy (SEM) and the copper ion adsorption capacity measurement. The result showed that EDTA and GO were successfully grafted on the surface of modified membrane and the hydrophilicity of the modified membrane increased. Roughness of membrane surface increased when the functional groups introduced on the surface. Adsorption for Cu2+ of modified membrane significantly improved. [ABSTRACT FROM AUTHOR]