Cellulose acetate blends

The importance of proper RO membrane selection has already been discussed. A review of commercially available RO membranes revealed five different basic membranes that could provide organic recovery. Cellulose acetate and cellulose acetate blends, aromatic polyamide, polyamide thin-film composite, cross-linked polyimine thin-film composite (FT-30), and polybenzimidazole were available when this work was performed. Only the first four types were commercially available. All membranes were available with excellent salt rejection (>97 sodium chloride). Two types of membranes, cellulose acetate and FT-30, have shown short-term (<2-months intermittent use) resistance... 

W.M. King, D.L. Hoemschemeyer and C.W. Saltonstall, Jr, Cellulose Acetate Blend Membranes, in Reverse Osmosis Membrane Research, H.K. Lonsdale and H.E. Podall (eds), Plenum Press, New York, pp. 131-162 (1972). 

Most MF, UF, RO, and NF membranes are synthetic organic polymers. NF membranes are made from cellulose acetate blends, cellulose triacetate (CTA), or polyamide composites such as the RO membranes, or they could be modified forms of UF membranes such as sulfonated polysulfone [27]. On the other hand, poly(vinyl alcohol) (PVA) is a significant polymer for nonaqueous applications. Chemical stmctures of a few of the prominent polymers are shown in Figure 42.4. 

Membrane polymer Polyamide Corr5)osite polyamide Cellulose-acetate blend Composite polyamide... 

A.W. and Wood, M.D., 1996, The influence of degree of substitution on blend miscibility and biodegradation of cellulose acetate blends. J. Environ. Polym. Degrad. 4,179-195. 

Boricha, A. G. and Murthy, Z. V. P. 2010. Preparation of N.O-carboxymethyl chitosan/cellulose acetate blend nanofiltration membrane and testing its performance in treating industrial wastewater. Chem. Eng. J. 157 393-400. 

Nanofiltration (NF) (TFCP), cellulose acetate blend (CAB), cellulose triacetate (CTA) TFCP 10-30 A flow Preferential sorption-capillary osmotic pressure Net applied pressure in excess over the... 

In the woik of Olde Riekerink et al. (2002), one type of UF (cellulose triacetate, CTA) membrane and one type of RO (cellulose acetate blend, CAB) membrane were selected for CO2 plasma modification. CTA ultrafilters are well known for their low fouling properties and CAB membranes are widely used for desalination. CO2 plasma treatment resulted in the gradual etching of the membrane s dense top layer. 

Liu, C. and Bai, R. 2005. Preparation of chitosan/cellulose acetate blend hollow fibers for adsorptive performance. J. Membr. Sci. 267 68-77. 

Buchanan, C.M. et al. (1992) Cellulose acetate blends with polyhydroxyalkanoates. Macromolecuks, 25, 7381. 

Meyer, J.M. and Elion, G.R. (1994) Starch cellulose acetate blends. US Patent S288S18 to USiVrmy, Natick Lab.). 

Uesaka T, Nakane K., Maeda S., Ogihara T, Ogata N. Structure and physical properties of poly(butylene) succinates/cellulose acetate blends, Po/y mer 41 (2000) 8449. 

AN, 0-Carboxy methyl chitosan/cellulose acetate blend nano filtration membrane was prepared in acetone solvent. It had been tested to separate chromium and copper fiom effluent treatment. The highest rejection was observed to be 83.40% and 72.60%, respectively (Alka et al., 2010). A chitosan/cellulose acetate/polyethylene glycol ultra filtration membrane was prepared with DMF as solvent. It was focused to be efficient in removing chromium from artificial and tannery effluent wastewater. The highest rejection rate was responding (Sudha et al., 2008).Cross-linked chitosan/polyvinyl alcohol blend beads were prepared and studied for the adsorption capacity of Cd from wastewater. The maximum adsorption of Cd(II) ions was foimd to be 73.75% at pH 6 (Kumar et al., 2009). 

Chun Xiu Liu and Renbi Bai (2006). Adsorptive removal of copper ions with highly porous chi-tosan/cellulose acetate blend hollow fiber membranes. Journal of Membrane Science 284(1 2), 313-322. 

Zhou W, He J, Du S, Cui S, Gao W. Electrospun silk fibroin/cellulose acetate blend nano-fibres structure and properties. Iran Polym J 2011 20 389-397. 

Duckett, K.E., Bhat, G.S. and Suh, H., Compostable Nonwovens from Cotton/ Cellulose Acetate Blends , Proceedings of the 1995 TAPPI Nonwovens Conference,... 

Modification of polymeric membrane materials through incorporation of hydrophi-licity results in membranes with low fouling behavior and high flux. Thus, literature presents sulfonated polysulfone/cellulose acetate blends applied in various compositions for obtaining ultrafiltration membranes, where their performance is improved by the inclusion of polyethyleneglycol into the casting solution as a nonsolvent additive in various concentrations. In this way, total polymer concentration, cellulose acetate, sulfonated polysulfone polymer blend composition, additive concentration, and their compatibility with polymer blends are optimized [133]. 

S. L. Gao, N. G. Zhou, X. Z. Zhang, and W. Zhang, Interfacial properties of ethyl cellulose/ cellulose acetate blends by HPLC. Chin. J. Process Eng. 7,152-154 (2007). 

Han, B. et al.. Preparation and characterization of cellulose acetate/carboxymethyl cellulose acetate blend ultrafiltration membranes. Desalination, 2013.311 80-89. 

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