Equilibrium, Thermodynamic, Reuse, and Selectivity Studies for the Bioadsorption of Lanthanum onto Sericin/Alginate/Poly(vinyl alcohol) Particles

Abstract

In a scenario of high demand, low availability, and high economic value, the recovery of rare-earth metals from wastewater is economically and environmentally attractive. Bioadsorption is a promising method as it offers simple design and operation. The aim of this study was to investigate lanthanum bioadsorption using a polymeric bioadsorbent of sericin/alginate/poly(vinyl alcohol)-based biocomposite. Batch system assays were performed to evaluate the equilibrium, thermodynamics, regeneration, and selectivity of bioadsorption. The maximum capture amount of lanthanum at equilibrium was 0.644 mmol/g at 328 K. The experimental equilibrium data were better fitted by Langmuir and Dubinin–Radushkevich isotherms. Ion exchange mechanism between calcium and lanthanum (2:3 ratio) was confirmed by bioadsorption isotherms. Thermodynamic quantities showed that the process of lanthanum bioadsorption was spontaneous (−17.586, −19.244, and −20.902 kJ/mol), endothermic (+15.372 kJ/mol), and governed by entropic changes (+110.543 J/mol·K). The reusability of particles was achieved using 0.1 mol/L HNO3/Ca(NO3)2 solution for up to five regeneration cycles. The bioadsorbent selectivity followed the order of lanthanum > cadmium > zinc > nickel. Additionally, characterization of the biocomposite prior to and post lanthanum bioadsorption showed low porosity (9.95 and 12.35%), low specific surface area (0.054 and 0.019 m2/g), amorphous character, and thermal stability at temperatures up to 473 K. This study shows that sericin/ alginate/poly(vinyl alcohol)-based biocomposites are effective in the removal and recovery of lanthanum from water.

Innovative Green Alginate‐Cellulose Composite for Light Lanthanides: Experimental Design and Comprehensive Studies on Kinetics, Equilibrium, Thermodynamics, and Reusability

“…This may indicate that the La(III), Pr(III), Ce(III), Nd(III) sorption on the alginate-cellulose was spontaneous reaction and was more efficient at low temperatures. These outcomes are in line with the findings achieved by da Costa et al [52] and Guo et al [53] Figure 7. a) Ca(II) ions release and pH changes during the La(III) ions uptake on the ALG 5 C 1 , b) pH value variation during sorption of La(III) ions on the ALG 5 C 1 composite as a function of phase contact time c) the probable hydrogen binding between alginate and cellulose and possible adsorption interaction mechanism (using La(III) ions as an example).…”

Cell Immobilization Using Alginate-Based Beads as a Protective Technique against Stressful Conditions of Hydrolysates for 2G Ethanol Production

“…Furthermore, both are polyelectrolytes with a wide range of laboratory and industrial applications, such as thickening agents, controlled release system, healing biomaterials, cell culture, ion exchange material for the removal of toxic compounds, etc. The potential of alginate to adsorb several biological and toxic compounds is well described in the literature [23][24][25]. When alginate and chitosan are used together, the formation of a polyelectrolyte complex is observed, receiving attention due to its high biocompatibility and potential in the development of tenacious biomaterials [26,27].…”