Highly Selective Removal of Organic Dyes from Aqueous Solutions with Chitin Beads Entrapping Rectorite

By blending chitin with rectorite and organic rectorite in an 8 wt % NaOH/4 wt % urea aqueous solution, we successfully fabricated millimeter-scale chitin/rectorite composite beads (BCRs) and chitin/organic rectorite beads (BCO), respectively, via an optimal dropping technology. The adsorption of the organic dyes on the BCRs and BCOs were investigated to evaluate the selective removal of methylene blue (MB) and methyl orange (MO) of different charges. Adsorption kinetics experiments were carried out, and the data fit a pseudo-second-order equation well. The results reveal that the BCR and BCO sorbents efficiently and selectively adsorbed MO and MB, respectively, from wastewater. The adsorption capacity (Q(e)) and removed percentage of MB by BCR were 0.1978 mg/g and 98.90%. The Q(e) and R values of MO by BCO were 0.3988 mg/g and 99.70%. Therefore, in this study, we dealt with the development of a clean and safe process for water pollution remediation. (C) 2014 Wiley Periodicals, Inc.