Cellulose acetate ultrafiltration membranes reinforced by cellulose nanocrystals: Preparation and characterization

Abstract

Cellulose nanocrystals (CNCs) were used as a sustainable additive to improve the hydrophilicity, permeability, antifouling, and mechanical properties of blend membranes. Different CNC loadings (0-1.2 wt %) in cellulose acetate (CA) membranes were studied. The blend membranes were prepared by a phase-inversion process, and their chemical structure and morphological properties were characterized by attenuated total reflectance-Fourier transform infrared spectroscopy, scanning electron microscopy, porosity, and mean pore size and contact angle measurement. The blend membranes became more porous and more interconnected after the addition of CNCs. The thickness of the top layer decreased and a few large holes in the porous substrate appeared with increasing CNC loading. In comparison with the pure CA membranes, the pure water flux of the blend membranes increased with increasing CNC loading. It reaches a maximum value of 76 LÁm 22 Áh 21 when the CNC loading was 0.5 wt %. The antifouling properties of the CA membrane were significantly improved after the addition of CNCs, and the flux recovery ratio value increased to 68% with the addition of 0.5 wt % CNCs. In comparison with that of the pure CA membranes, the tensile strength of the composite membranes increased by 47%. This study demonstrated the importance of using sustainable CNCs to achieve great improvements in the physical and chemical performance of CA ultrafiltration membranes and provided an efficient method for preparing high-performance membranes.

Cellulose acetate ultrafiltration membranes customized with copper oxide nanoparticles for efficient separation with antifouling behavior

“…[7][8][9] On account of desirable film-forming properties fabrication of CAbased UF membranes for the purpose of water treatment applications is most widely reported. [10][11][12][13][14] CA and polysulfone blend UF membranes exhibited high water flux, more porosity, and high water content in the presence of polyethylene glycol (PEG) additives. 15 The development of surface-modified polymeric UF membranes using nanoadditives has become more popular.…”

“…The benefits of incorporation and in‐situ immobilization of nanoadditives to improve the UF membrane performance are also reported 7–9 . On account of desirable film‐forming properties fabrication of CA‐based UF membranes for the purpose of water treatment applications is most widely reported 10–14 . CA and polysulfone blend UF membranes exhibited high water flux, more porosity, and high water content in the presence of polyethylene glycol (PEG) additives 15 …”

Effects of Gelatin and Nano‐ZnO on the Performance and Properties of Cellulose Acetate Water Membranes

“…Nowadays, the world is facing a clean water supply crisis, especially in developing countries, which has been worsened by overpopulation and climate changes [1][2][3]. The most widely used and advantageous method of water purification is membrane separation because it requires little or no chemicals, can be easily scaled up, and requires relatively low energy, to name but a few [4][5][6][7][8]. Numerous ceramics and polymers have been employed as membranes for water purification, giving a range of properties.…”

“…Cellulose, the most abundant polymer on the earth [8,11], and its derivatives show versatility in the preparation of membranes, from ultrafiltration to reverse osmosis [12]. Among different cellulose esters, cellulose acetate (CA) is very common due to desirable properties such as good toughness, high biocompatibility, good desalting, high potential flux, and relatively low cost [5,13].…”

“…Among different cellulose esters, cellulose acetate (CA) is very common due to desirable properties such as good toughness, high biocompatibility, good desalting, high potential flux, and relatively low cost [5,13]. However, neither the fouling ability nor the chemical and thermal resistance of cellulose acetate is satisfactory [8,14,15].…”