Adsorption of Brilliant Green from Aqueous Solutions onto Crosslinked Chitosan Graft Copolymers

Abstract

In this study, graft copolymerization of itaconic acid (IA) and crotonic acid (CA) onto the crosslinked chitosan beads were carried out using ammonium persulfate as initiator. Grafted chitosan beads were characterized by FT-IR analysis and grafting percentage determination. Grafting efficiency and add-on percentages values of grafted chitosan beads were determined as 23-29 and 32-47%, respectively. Then, equilibrium isotherms and kinetics of brilliant green adsorption onto grafted chitosan beads were investigated. The results indicated that the pseudo-second-order kinetic model fitted better than the data obtained from pseudo-first-order model for the adsorption of brilliant green onto grafted chitosan beads. The fit of data for brilliant green (BG) adsorption onto grafted chitosan beads suggested that the Langmuir model gave closer fittings than the Freundlich model.

Study on adsorption, regeneration, and reuse of crosslinked chitosan graft copolymers for Cu(II) ion removal from aqueous solutions

“…When the content of glucosamine (degree of deacetylation) of chitin is higher than about 50%, it is as named chitosan, and it becomes soluble in an aqueous acidic medium [16,17]. The presence of amino groups in chitosan besides hydroxyl groups is highly advantageous for modification reactions [2,18]. Therefore, several modifications were carried out on the hydroxyl and amino groups on glucosamine units of chitosan previously.…”

“…Therefore, several modifications were carried out on the hydroxyl and amino groups on glucosamine units of chitosan previously. Crosslinking on chitosan is an effective way on improving its physical and mechanical properties [2,19]. Chemical resistance is very important property for an adsorbent.…”

“…The chemical contamination of water with toxic materials such as heavy metals, aromatic molecules, and dyes is an important environmental problem [1,2]. Copper, which is one of the heavy metals, interferes into natural waters with various industrial processes such as mining, metallurgy, and fertilizer industries.…”

“…Chitosan is obtained by deacetylation of chitin under alkaline conditions. Chitosan is a linear polysaccharide composed of glucosamine and N-acetyl glucosamine units linked by (1)(2)(3)(4) glycoside bonds. When the content of glucosamine (degree of deacetylation) of chitin is higher than about 50%, it is as named chitosan, and it becomes soluble in an aqueous acidic medium [16,17].…”

“…In recent years, polymeric adsorbents have been used to remove heavy metal ions and basic dyes from waste waters [4][5][6][7][11][12][13][14][15]. In parallel, the use of natural polymers (e.g., cellulose, starch, chitosan, and alginate) and their derivatives for the removal of heavy metal ions from wastewater has become important by reason of their biodegradability [2].…”