Title
Renewable lignin-based biomaterials for the adsorption of Co(II) ions from wastewaters
Authors
ELENA UNGUREANU, EUGEN ULEA, COSTEL SAMUIL, OVIDIU C. UNGUREANU, MARIA E. FORTUNĂ, RĂZVAN ROTARU, BOGDAN-MARIAN TOFĂNICĂ and VALENTIN I. POPA

Received May 9, 2024
Published Volume 58 Issue 7-8 July-August
Keywords Co(II) ions, Sarkanda grass lignin, adsorption, Triticum aestivum L., environmental pollution

Abstract
The current study examines the adsorptive potential of a biomaterial resulting from the extraction of cellulose, Sarkanda grass lignin, for the retention of Co(II) from aqueous medium under static conditions. The initial solution pH, initial concentration of Co(II), the adsorbent dose and the contact time between the adsorbent and the adsorbate were the main parameters preliminarily tested in order to accurately establish the optimal experimental conditions. The adsorption capacity of Sarkanda grass lignin was evaluated through surface analyses, the application of the Freundlich and Langmuir models to establish chemical equilibrium conditions, the Lagergren I and Ho-McKay II models for process kinetics, and biological stability analysis of specific indices. The number of germinated seeds or germination energy for the seeds of Triticum aestivum L, Glosa variety, introduced in the contaminated adsorbent and in the filtrates resulting from the phase separation was also evaluated. The results obtained through the aforementioned analysis methods indicate that Sarkanda grass lignin may be a promising solution for the adsorption of Co(II) from wastewater. This is evidenced by the observed adsorption capacity and the time required for the adsorption process.