Adsorption dynamics of dye onto crab shell chitosan/neem leaf composite

Abstract

<jats:title>Abstract</jats:title> <jats:p>The aim of this study was to evaluate the adsorption dynamics of crab shell chitosan/neem leaf composite against methylene blue dye at varying concentrations (50 and 200 mg/L), bed depths (2.5 and 5.0 cm), and flow rates (2.17 and 2.90 mL/min). The chitosan composite has a specific surface of 258 m2/g. Its surface is rich in amine/amide groups. The results reflect better dye adsorption at higher operating conditions. The maximum dye adsorption capacity observed was almost 77 mg/g. The kinetics models showed good correlation with the experimental data and described the breakthrough behaviour of dye removal. The Thomas model predicts external and internal diffusion as the rate controlling mechanisms, while the Adams-Bohart model indicates a simultaneous steady state process of intraparticle diffusion and ionic interaction. Chitosan composite is a promising adsorbent candidate for dye wastewater treatment.</jats:p>

Synthesis, Characterization, and Application of Ag-Biochar Composite for Sono-Adsorption of Phenol

“…According to the international regulatory agencies of the World Health Organization and EPA, the estimated value of phenol >1 ppm is carcinogenic and non-acceptable in water resources for inhabitants (Zarin et al, 2018). Due to its wide use and hazardous consequences, the removal of phenol from wastewater attains considerable interest among researchers by different conventional and advanced methods, that is, including adsorption/biosorption (Francis et al, 2020), biological degradation (Tomei et al, 2021), electrochemical oxidation (Yavuz and Koparal, 2006), solvent extraction (Liu et al, 2013), membrane filtration (Li et al, 2010), and photocatalytic degradation (Mohamed et al, 2020).…”

Adsorption of Reactive Dye onto Uçá Crab Shell (Ucides cordatus): Scale-Up and Comparative Studies

“…The uçá crab (Ucides cordatus) is a species of mangrove that is found in tropical and subtropical regions, being the most important crustacean that inhabits the mangrove forests of the Brazilian coast [21]. This crustacean is commonly used in human consumption, and the shells have been used as an adsorbent material for water pollutants [22,23]. Crab shell is a highly resistant material, consisting mainly of calcium carbonate and chitin, associated with protein and mineral salts [24].…”