Removal of Copper from Water by Adsorption with Calcium-Alginate/Spent-Coffee-Grounds Composite Beads

Abstract

Calcium Alginate/Spent-Coffee-Grounds composite beads (CA-SCGs beads), which were made of two different proportions of alginate and spent-coffee-grounds (3:3 and 3:10), respectively, were used to adsorb Cu2+ in aqueous solution. These beads were compared with calcium alginate beads (CA beads) and spent-coffee-grounds (SCGs) in terms of adsorption capacity and rate of adsorption. The experiments were carried out at an initial pH of 4 at 30 °C with initial concentrations of Cu2+ from 10 ppm to 100 ppm. Equilibrium data was fitted with Langmuir, Freundlich and Sips models, and a pseudo-second-order kinetic equation. The Sips model showed the best correlation with the experimental values. CA-SCGs (3:3) beads showed a faster adsorption rate versus the CA beads. Also, CA-SCGs (3:3) beads showed a larger capacity of adsorption according to the Sips model, but not in the Langmuir model. FT-IR spectra and SEM images were taken for characterization. This study has shown that the CA-SCGs (3:3) beads have a synergistic effect, combining the capacity of adsorption of CA beads with the kinetics of the SCGs. The CA-SCGs beads have proven to be an effective adsorbent of Cu2+. Therefore, they can provide a use for the SCGs; which are considered pollutants in landfills.

Adsorption of Ni2+ and Cd2+ from Water by Calcium Alginate/Spent Coffee Grounds Composite Beads

“…SCGs have been encapsulated before in CA in our previous study, showing greater adsorption capacity for Cu 2+ in water and improved kinetics than CA alone at concentrations between 10 to 100 ppm of copper at pH 4 and 30 • C [17]. In the previous study, the larger adsorption by CA-SCG beads in comparison to the CA beads was seen in the lower range of concentrations (10 to 30 ppm).…”

“…The reported estimated equilibrium constants in their study were: K Cu = 649 kgL/mol 2 , K Cd = 172 kgL/mol 2 and K Ni = 30.8 kgL/mol 2 [46]. Our previous study with Cu 2+ showed a great improvement in the kinetics of adsorption by the CA-SCGs beads versus the CA beads, despite that the study was at pH of 4, with more protons competing with the metal for adsorption sites [17]. Nevertheless, the current study shows improvement in the kinetics of adsorption of Cd 2+ in CA-SCGs versus the CA beads, but did not show any improvement in the kinetics of adsorption of Ni 2+ in CA-SCGs versus the CA beads.…”

“…Sci. 2019, 9, 4531 3 of 21 At these concentrations, the percentages of adsorption were closer to 100% versus the CA alone, approaching the goal of total metal removal from the water [17]. Most of the contamination by heavy metals in water is at levels of trace concentrations.…”

Recent Trends in Three-Dimensional Bioinks Based on Alginate for Biomedical Applications

“…It is worth noting that we are still a great distance from organ printing. Even though recent deposition and manufacturing systems permit us to develop structures similar to tissue in their composition, the progression of entirely functioning tissue is a much more significant step [ 154 , 155 , 156 , 157 , 158 , 159 , 160 , 161 , 162 , 163 , 164 , 165 , 166 , 167 , 168 , 169 , 170 , 171 , 172 , 173 , 174 , 175 , 176 , 177 ].…”

Recent advances in novel remediation processes towards heavy metals removal from wastewaters

“…This newly synthesized nano-particle was found to be very suitable in heavy metals removal because it shows a higher adsorption rate of 0.700, 0.451, and 0.790 mg.mg -1 for copper, nickel, and aluminum respectively. Therefore, it establishes itself as a promising sorbent for heavy metals sorption (Khan et al, 2020;Torres-Caban et al, 2019).…”