Cellulose acetate-based membrane for wastewater treatment—A state-of-the-art review (original) (raw)
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The development of cellulose acetate blend membranes using a commercial grade Mycell cellulose acetate and cellulose diacetate with suitable pore structure is discussed. These membranes were characterized in terms of resistance of the membrane, pure water flux, the molecular weight cutoff, water content, pore size, and porosity. The removal of copper metal ions by this blend membrane using polyethyleneimine as a chelating agent was studied. The effects of copper ion concentration and casting solution composition on separation are also discussed. A possible correlation between feed and permeate concentration of copper ion is evaluated.
Preparation and characterization of cellulose acetate propionate membrane
International Journal of Advances in Applied Sciences (IJAAS), 2024
Membrane technology is a technique in water and wastewater treatment that has many advantages. This study focuses on the manufacture and characterization of cellulose acetate propionate (CAP) membranes using the phase inversion method. The CAP is preferable since it is a biopolymer that is environmentally friendly and cheap. The production of CAP membrane was carried out using phase inversion method, and varied in 3 different concentrations of CAP i.e., 13, 14, and 15% wt., with additional material of polyethylene glycol (PEG). The characterization was conducted using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) analysis to determine its morphology, pores, and functional groups. The results show that the membrane containing 13% wt. CAP exhibits higher porosity with more macropores than a membrane with 14 and 15% wt. CAP. However, membranes with higher concentrations of CAP show more uniform pores and fewer macropores. FTIR analysis confirmed the presence of functional groups in the membrane such as C-O, -CH3, C=O, C-H, and OH. It is also found that there is a shift in Wavenumber due to the increase in the concentration of CAP in each membrane.
Environmental Progress, 2005
A technique for postsynthesis modification of a cellulose acetate ultrafiltration membrane with possible application in water and wastewater treatment is studied. The technique used an oxidizing agent (persulfate) to develop free radicals on the membrane surface, and that was expected to promote grafting of hydrophilic macromolecules (polyethylene glycol). A chaintransfer agent (2-mercaptoethanol) was tested to control the grafting process, avoiding the formation of long chains that usually lead to high permeability losses in other graft techniques. The modifications aimed at the decrease of the fouling susceptibility of the membrane studied. The possibility of an increase in rejection was also investigated. The membrane was characterized before and after modification, by attenuated total reflectance-Fourier transform-infrared spectroscopy, scanning electron microscopy, atomic force microscopy, and in terms of the rejection of neutral reference solutes. The information given by the different techniques of characterization provided strong evidences of the occurrence of modification, although permeation of (real) foulants was the decisive test. To obtain information about the fouling tendency of the nonmodified and modified membranes, two different kinds of foulants were used: a humic acid (usually found in surface waters) and textile auxiliaries (representing one of the most important industries in Portugal). The results showed an increase in the rejections of the humic acid, and significant improvements in the performance of the membrane with respect to fouling tendency in the case of the textile auxiliaries.
Preparation of cellulose triacetate/cellulose acetate (CTA/CA)-based membranes for forward osmosis
Journal of Membrane Science, 2013
Cellulose triacetate/cellulose acetate (CTA/CA)-based membranes for forward osmosis (FO) were prepared by immersion precipitation. Casting composition and preparation conditions-1,4-dioxane/ acetone ratio, CTA/CA ratio, substrate type, casting thickness, evaporation time and annealing temperaturewere tested for their effects on formation and subsequent performance of membranes. Membranes were characterized by various methods, and their performances were tested against commercially available membranes. The FO membrane prepared under optimized composition and conditions had a smooth surface and showed higher water flux and salt resistance than the commercial membranes. Annealing improved the membrane performance by removing residual additives and solvents. The computerized image processing of optical microscopy images was shown to be useful for assessing the membrane substrates.
Environmental Technology, 2019
In order to enhance characteristic performance of cellulose acetate (CA) membranes, a novel nanofiller synergy is adopted herein for desalination purpose. Activated zinc oxide and aerosilica synergy in seven different ratio based combinations were introduced into CA matrix adopting solution mixing technique. The functionalized nanofillers loading impact on membranes surface texture, crystalline structural difference, functional groups presence, thermal decomposition and phase transition temperatures were scrutinized. The solely membranes were practically employed to determine salts (NaCl and MgCl2) rejection tested by dead end filtration system. Time dependent flux rate and fouling study was performed to decide the reuseability of 2 nanocomposite membranes. The results validate a remarkable improvement by idiosyncratically synthesized nanocomposite membranes.