Synthesis of a chitin-based biocomposite for water treatment: Optimization for fluoride removal

Journal of Fluorine Chemistry (Impact Factor: 1.95). 08/2009; 130(8):718–726. DOI: 10.1016/j.jfluchem.2009.05.012

ABSTRACT The optimum composition of a chitin-based biocomposite was determined based on both its fluoride adsorption capacity and its chemical resistance in acid aqueous solution. Parameters such as the chitin content, additive content, catalyst content, chitin particle size, degree of acetylation of chitin and effect of pH on adsorption were evaluated. It was possible to chemically reinforce chitin while keeping an acceptable fluoride adsorption capacity onto the chitin-based biocomposites. Optimum chitin content (60%) was limited by the polymer–biopolymer anchoring capacity. An amine-based additive was used to improve the biocomposite adsorption capacity; however, its inclusion was not suitable in terms of biocomposite chemical resistance. The chitin particle size had no effect on adsorption capacity, and the degree of acetylation of chitin notably modified biocomposite adsorption capacity. On the other hand, the biocomposite chemical resistance was notably improved compared to pure chitin. The physicochemical properties of the optimum chitin-based biocomposite showed its potential for being used in continuous adsorption processes.

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Available from: Keiko Shirai, Jul 17, 2015
    • "Potential presence of aluminum ion – a neurotoxic constituent – in water treated with activated alumina [3], in fact, has been a trigger for the search for a safer, biomass-based alternative. Chitosan and modified chitosan have been used as adsorbents to remove fluoride from drinking water [4] [5] giving a removal efficiency of 4.7 mg of fluoride per gram of dry adsorbent. Calcium chloride treated and dried algal biomasses of Anabaena fertilissima and Chlorococcum humicola were showed to remove 2.8 mg and 4.4 mg of fluoride, respectively, per gram of dry adsorbent [6]. "
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