Separation of Cr(VI) on Chitosan Membranes

Abstract

Chitosan membranes were used for hexavalent chromium removal. Investigations covered membranes produced by phase inversion (wet-method). The modifications of membranes were made by acetylated and cross-linked Cu(II). In the experiments chitosan produced by the Sea Fisheries Institute, Poland, was used. The metal ions were removed on chitosan membranes during membrane processes. The modifications and the effect of the pH of the solution on the separation properties of membranes were determined. The concentration of metal ions was measured by the method of inductively coupled plasma (ICP) atomic emission spectrometry.

Production and characterization of thick, thin and ultra-thin chitosan/PEO films

“…Metal binding occurs due to the electrostatic attraction between the dissociated CrO 4 2− ions in solution and NH 3 + group of chitosan (Qian, Huang, Jiang, He, & Wang, 2000). The metal-binding capacity of chitosan films varies with type of metal ions, extent of film crystallinity, pH value of the solution, number of available amino groups, and physical adsorptive ability of the films (Kurita, Sannan, & Iwakura, 1979;Modrzejewska & Kaminski, 1999). Apparently, films with larger surface area per weight have more amino groups available to interact with chromium ions and consequently remove more metal ions from solution.…”

Fabrication and electrochemical study of monodisperse and size controlled Prussian blue nanoparticles protected by biocompatible polymer

“…It is an attractive biocompatible, biodegradable, and nontoxic natural biopolymer that has been applied to many fields, such as metal adsorption [18], enzyme immobilization [19] and the controlled release of drugs [20]. Recently, chitosan has also been used for preparation of nanocomposites [21][22][23].…”

A simple sulfuric acid pretreatment method to improve the adsorption of Cr(VI) by chitosan

“…Optimum pH was reported as low as pH 2 by Lopez de Alba et al 22 and as high as pH 9 by Cha et al 23 Most of the research identifies pH 3-4 as being most effective. [17][18][19][20] One reason for this broad reported pH binding range could be the differing properties of the various chitosans used by different researchers, or perhaps a more likely explanation is the change in solution pH caused by chitosan itself. As the mixture of chitosan in water is stirred, the pH of the water rises.…”