Safranin-O Dye Removal from Aqueous Solution Using Superabsorbent Lignin Nanoparticle/Polyacrylic Acid Hydrogel

Abstract

Alkali lignin (AL) modified by ethylene glycol and lignin nanoparticles (LN) was prepared through the acid precipitation technology. Lignin nanoparticle/polyacrylic acid (LN/PAA) hydrogel was prepared using copolymerization reactions. LN and LN/PAA hydrogel were investigated using GPC, SEM, FT-IR spectroscopy, and TGA-DTG analysis. The sizes of the nanoparticles were assessed using DLS. LN/PAA hydrogel was used to remove Safranin-O from an aqueous Solution. The optimal conditions for absorption provided at pH 7, an initial concentration of dye of 1.5 gr.L -1 , and an adsorbent dosage of 0.1 gr. Also, the optimal time for LN and LN/PAA hydrogel were 100 min and 450 min, respectively. Both absorbent LN and LN/PAA hydrogel showed good agreement with the Langmuir isotherm. The maximum absorption capacities of LN and LN/PAA hydrogel were determined to be 100 mg.gr -1 and 1666.6 mg.gr -1 , respectively. Both absorbent LN and LN/PAA hydrogel follow the pseudo-second kinetic model and the intraparticle diffusion model.

Fabrication of Colored Polymeric Membrane Using Clay-Based Nano Pigments of Safranin O (SO) Dye

“…Halboos and Hussain used nano iron oxide (Nano FeO) to remove Safranin O dye from aqueous media [19]. Azimvand et al (2018) synthesized lignin nanoparticle-g-polyacrylic acid in the presence of potassium persulfate as the radical initiator and used it as an adsorbent for the removal of Safranin O dye (138.88 mg g −1 ) [22]. Das et al (2021) compared the adsorption efficiencies of coconut coir and its acid-treated forms (phosphoric acid and sulfuric acid) for the removal of Safranin O dye where they confirmed the maximum efficiency of phosphoric acid-treated coconut coir [23].…”

“…Das et al (2021) compared the adsorption efficiencies of coconut coir and its acid-treated forms (phosphoric acid and sulfuric acid) for the removal of Safranin O dye where they confirmed the maximum efficiency of phosphoric acid-treated coconut coir [ 23 ]. Parmar and Shah observed 97% of Safranin O dye adsorbed on the surface of tamarind seeds [ 24 ]. Didehban et al (2016) compared the adsorption capacities of lignin nanoparticles and a polyacrylic acid hydrogel for the adsorption of Safranin O dye and confirmed a 1666.6 mg g −1 adsorption of dye onto the polyacrylic acid hydrogel [ 25 ].…”