Chromium (VI) Ion Adsorption Features of Chitosan Film and Its Chitosan/Zeolite Conjugate 13X Film

Abstract

This research evaluated the importance of the adsorption properties of chitosan a chitosan/zeolite conjugate film for the removal of Cr(VI) ions from solutions in the 5–260 mg/L concentration range, when the pH was adjusted to 4.0 and 6.0. The uptake capacities of the films formed by chitosan and by the chitosan/zeolite conjugate were calculated by mass balance. The equilibrium isotherms were fitted to the Langmuir, Freundlich and Redlich-Peterson models. The chitosan film seems to be a good sorbent for Cr(VI) at pH 4, but its physical instability suggests the need for a more resilient support. Due to this fact zeolite was added to the chitosan matrix in solution and a chitosan/zeolite (CS/Zeo) film was thus formed. The solubility of the film and the characterization of the different matrices by FTIR, TGA and X-Ray showed that a cross-linked structure was formed between the chitosan and zeolite and the solubility of the film increased. In this study, the low manufacturing cost of the CS/Zeo matrix, the good uptake of Cr(VI) at acidic pH (17.28 mg/g) and the non desorption of Cr(VI) from the film in water suggests this combination should be tested in industrial environment.

Mercury(II) Removal with Modified Magnetic Chitosan Adsorbents

“…The latter could be easily explained by the presence of amino groups on the polymer matrix, which can interact with metal ions of the solution by ion exchange or other complexation reactions (mainly chelation) [4,5]. The high content of amino groups also makes possible many chemical modifications on the polymer with the purpose of improving its adsorption features, such as selectivity and adsorption capacity [6,7]. Its adsorption performance can be further improved by cross-linking with reagents such as glutaraldehyde, tripolyphosphate salts, epichlorohydrin, ethylene glycol or diglycidyl ether, which can stabilize chitosan in acid solutions and increase its mechanical properties [8].…”

Adsorption of hexavalent chromium by graphite–chitosan binary composite

“…R 2 and R L in the range of 0-1 showed applicability/fit of Langmuir model. Adsorption capacity q m and b (b = ratio of C e /q m , where q m is maximum adsorption capacity of adsorbent) were 105 mg g −1 and 0.367 l mg −1 , respectively, for GCB composite compared with biosorbents in table 2 [30,31]. Adsorption capacity of chitosan for Cr(VI) reported 23 mg g −1 [32] under similar conditions.…”

Review of fungal chitosan: past, present and perspectives in Brazil

“…Abdull Rasad et al [53] , Tajdini et al [54] , Gomathi et al [55] , Harris et al [56], Li et al [57] , Batista et al [58] , Yu et al [59] , Moussa et al [60] , Paiva et al [61] , Oliveira et al [62] , Tayel et al [63] , Taillandier et al [64] , Souza et al [65] • Kitozyme: Belgian company pioneer in the production of highly pure non-animal chitosan. It holds some unique patents on the production processes of polymers, such as chitosan.…”