Synthesis and Characterization of Glutamic-Chitosan Hydrogel for Copper and Nickel Removal from Wastewater

Abstract

Abstract:Chitosan was reacted with four concentrations (2.5, 5, 10 and 20 mmol) of glutamic acid resulting in four types of glutamic-chitosan hydrogels (GCs), the activity of the resulted compounds on the removal of copper(II) and nickel(II) from wastewater were tested. The results indicated that by increasing glutamic acid concentration from GCs-1 to GCs-4, the efficiency of removing Cu(II) and Ni(II) were decreased, which may be due to a decrease in the pore size of the hydrogels as a result of the increased degree of crosslinking.

A Comparative Study on Cu2+, Zn2+, Ni2+, Fe3+, and Cr3+ Metal Ions Removal from Industrial Wastewaters by Chitosan-Based Composite Cryogels

“…At pH > 5, the precipitation of Cu(OH) 2 occurs, and thus the q e values started to decrease. The influence of pH on the removal of Cu 2+ ions by the CS-based cryogels is almost similar with that reported for other sorbents containing CS as matrix [19,20,23,24,29,30,35,36]. Based on the above results, the pH value of the wastewater was adjusted to 5 when the sorption of Cu 2+ ions was further evaluated.…”

“…This behavior is associated with many sites/functional groups able to remove efficiently a high quantity of HMIs, while the number of HMIs distributed per sorbent mass unit decreased, accordingly, with the increase of the sorbent dose [14,23,36]. For instance, the saturated sorption capacity of CPLH + , CGCS, and CGCS_CPLH + sorbents decreased from 15 (Figure 2B) when the sorbent dosage increased from 0.01 to 0.04 g. The RE values were around 12%, 40%, and 80% for CPLH + , CGCS, and respectively, CGCS_CPLH + sorbents at a sorbent dose higher than 0.03 g. A RE value higher than 80% was achieved when the Cu 2+ ions removal was studied using single-component aqueous systems [14,20,35,36]. Considering the RE values, the optimal sorbent dose of 0.035 g was chosen for all upcoming sorption experiments.…”

“…Among the available biopolymers, CS has the highest sorption performance toward HMIs [10][11][12] due to its abundant -NH 2 and -OH groups. Its sorption capacity has been further improved by functionalization with diacetylmonoxime [17] and polyhexamethyleneguanidine [18] or grafting of malic acid [19] or glutamic acid [20] onto CS matrix. Nevertheless, CS has poor mechanical properties and exhibits low chemical stability in harsh aqueous environments such as HMIs-containing wastewaters.…”

The Synthesis of Carboxymethyl Cellulose‐Based Hydrogel from Sugarcane Bagasse Using Microwave‐Assisted Irradiation for Selective Adsorption of Copper(II) Ions

“…As shown in Figure 6, the best CMC/PVA ratio of hydrogel preparation for Cu(II) ion adsorption was 25% CMC at pH 5, of which approximate 2.3 mg/g could be adsorbed or a 92.4% removal from the solution. The previous studies also reported that pH 5 offers the optimum adsorption for Cu(II) ions [38,47]. The decrease in adsorption capacity at a higher pH (7 and 9) can be explained by the formation of Cu(OH) 2 , an insoluble form, which is precipitated rather than adsorbed onto the hydrogel.…”

Special Issue: Chitin, Chitosan and Related Enzymes

“…Synthesis and Characterization of Glutamic-Chitosan Hydrogel for Copper and Nickel Removal from Wastewater [ 1 ] . Chitosan preparations were treated with various concentrations of glutamic acid resulting in different types of glutamic-chitosan hydrogels that were tested for the removal of copper(II) and nickel(II) from wastewater.…”