Composites with alginate beads: A novel design of nano-adsorbents impregnation for large-scale continuous flow wastewater treatment pilots

Saudi J Biol Sci. 2020 Oct;27(10):2499-2508. doi: 10.1016/j.sjbs.2019.11.019. Epub 2019 Nov 25.

Abstract

The sorption capacity of cadmium (Cd (II)) on three new generated nanocomposite beads sodium alginate (SA) based; SA-Clay (SA-C) beads, SA-Phosphate (SA-P) beads, and SA- Activated Charcoal (SA-Ch) beads was investigated in a batch scale, then a continuous flow reactor. The highest adsorption capacity (137 mg/g) was obtained for SA-Ch using 1000 mg/L of initial Cd (II). The isotherm results showed that the adsorption equilibrium is compatible with the Langmuir isotherm and the sorption capacity of SA-Nano-adsorbent beads is very high. The models used for representing kinetic data was given that the removal of Cd (II) be well-fitted by second-order reaction kinetics. For the fixed bed column treatment, the maximum breakthrough times were 30, 38, and 48 h respectively for the SA-C, SA-P, and SA-Ch. According to the obtained results, it was concluded that SA-Nano-adsorbent bead is an excellent designed material as a nanocomposite for cadmium elimination from wastewater in a continuous treatment process.

Keywords: Cadmium(II); Fixed-bed column; Nano-adsorbents encapsulation; Sodium alginate.