Removal of Copper(II) from Aqueous Solutions by Chitosan Adsorption

Carbon nanotube–chitosan composite electrodes for electrochemical removal of Cu(II) ions

“…As an inexpensive, widely used and nontoxic polysaccharide biopolymer, CS displays excellent film-forming ability, high hydrophilicity, and good biocompatibility [21][22][23][24]. Because CS has abundant amino (-NH 2 ) and/or hydroxy (-OH) functional groups which serve as coordination sites and exhibit a high specificity toward metal ions [25][26][27], CS has been integrated with CNT to form CNT-CS composites to effectively remove Cu 2+ from aqueous solutions by adsorption method [28] or to determine Cu 2+ by anodic stripping voltammetry [29]. Unfortunately, so far the exploration on the application CNT-CS composite materials for electrosorption is hardly reported.…”

Effects of chitosan membrane morphology on copper ion adsorption

“…The number of amino groups bound may increase up to two to three at pH 5-6. At pH 6-8, three amino groups and one hydroxyl group would bind with one Cu 2+ [34].…”

“…Transition metals are mainly adsorbed via reported that about 20% of the amino group of chitosan is protonated even at pH 6.9 and the reactions in Eqs. (1) and (2) compete during adsorption [34].…”

“…It can be assumed that a high concentration of SO 4 2− in the electrolyte causes adsorption of these anions by polymer and decreases the positive value of the . Consequently, chitosan possesses a negatively charged character- istic and shows additional ability to increase its uptake capacity to Cu 2+ (electrostatic mechanism) [34].…”

Heterogenization of copper catalyst for the oxidation of phenol, a common contaminant in industrial wastewater

“…The Cu(II) concentration in solution was monitored for 5 h, considering that all the adsorbent materials presented quite rapid adsorption rates at the first 2 h where equilibrium was reached, then adsorption contact time of 5 h was used for all further experiments. For instance, studies with chitosan have reported immediate adsorption uptake after 1 h [28].…”