Lignin from Agro-Industrial Waste to an Efficient Magnetic Adsorbent for Hazardous Crystal Violet Removal

Abstract

The presence of cationic dyes, even in a tiny amount, is harmful to aquatic life and pollutes the environment. Therefore, it is essential to remove these hazardous dyes to protect the life of marine creatures from these pollutants. In this research, crystal violet (CV) dye elimination was performed using a lignin copper ferrite (LCF) adsorbent. The adsorbent was synthesized and characterized using FTIR, Raman, SEM, EDX with mapping, and VSM, which proved the successful formation of magnetic LCF. Adsorption experiments were performed using different effective parameters. The highest adsorption potential (97%) was executed at mild operating conditions, with a 5 min contact time at room temperature and pH 8. The adsorption kinetic study utilized four kinetic models: first-order, second-order, intraparticle diffusion, and Elovich. The results revealed that the adsorption process complies with the pseudo-first-order with a maximum adsorption capacity of 34.129 mg/g, proving that the adsorption process mechanism is a physical adsorption process. Three isotherm models, Langmuir, Freundlich, and Temkin, were examined. The adsorption mechanism of CV onto LCF was also followed by the Langmuir and Freundlich models. The thermodynamic parameters were examined and revealed that the adsorption onto LCF was an exothermic process. It was proposed that the adsorption process is a spontaneous exothermic process. LCF appears to forcefully remove toxic CV dye from textile wastewater.

Fe3O4 Nanoparticle/Hyper-Cross-Linked Polymer Composites for Dye Removal

“…Under the optimal condition, the Fe 3 O 4 /HCP TPB exhibited excellent adsorption performance for CV from wastewater with a removal efficiency of 94.1%. Table depicts a comparison between Fe 3 O 4 /HCP TPB and other magnetic adsorbents. − The high adsorption capacity of Fe 3 O 4 /HCP TPB could be due to the presence of abundant aromatic and alkyl groups in its structure, resulting in π–π and hydrophobic interactions between Fe 3 O 4 /HCP TPB and CV. After 6 adsorption–desorption cycles with ethanol as the regenerant, the removal efficiency was still 81.7%, indicating good reusability.…”

A Fixed-Bed Column with an Agro-Waste Biomass Composite for Controlled Separation of Sulfate from Aqueous Media

“…In particular, the development of bioadsorbents has received greater attention, since renewable materials offer cost advantages over conventional synthetic resins. Common and prevalent waste materials (e.g., from black liquor) are lignin and lignin-derived materials from (agro-)waste as bioadsorbents for cation [16,17] or anion contaminants [18].…”