Covalent organic framework and montomorillonite nanocomposite as advanced adsorbent: synthesis, characterization, and application in simultaneous adsorption of cationic and anionic dyes

Abstract

In this work, Schiff base network-1 (SNW-1), as a new generation of covalent organic frameworks (COFs), was synthesized and modified by fabrication of a composite with clay mineral montomorillonite (Mt). It was used for simultaneous removal of anionic and cationic dyes from aqueous solutions. The fabricated composite was characterized successfully with various techniques. Tartrazine (TT) and methylene blue (MB) were selected as model anionic and cationic dyes, respectively. The effects of the percentage of each component in the composite, initial pH, and initial dye concentration were evaluated on the adsorption capacity. Adsorption reaction models and adsorption diffusion models were used to study the kinetic process of adsorption. Adsorption of both dyes reached equilibrium after 40 min. The obtained results were fitted to Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich (D-R) models to predict the isotherms of adsorption. Under optimum conditions for removal of each dye with the composite, the maximum adsorption capacity of 519.2 and 602.7 mg g −1 were obtained for TT and MB, respectively. The used SNW-1/Mt composite could be regenerated by salty methanol. The high adsorption capacity and excellent reusability make SNW-1/Mt composite attractive for the simultaneous removal of anionic and cationic dyes from aqueous solutions.

Hydrothermally engineered Eriobotrya japonica leaves/MgO nanocomposites with potential applications in wastewater treatment

“…The dyes cause cancer, mutagens, teratogens, cardiovascular shock, vomiting, gastrointestinal pain, diarrhea for human health (Bentahar et al, 2016), and water contamination with dyes causes severe environmental and aquatic life problems (El Messaoudi et al, 2021c). Among these dyes, tartrazine is an acidic azo dye (Arabzadeh et al, 2016) used in the food, cosmetics, pharmaceuticals, drugs, and textile industries (Khataei et al, 2020). Tartrazine can cause thyroid cancer, asthma, eczema, and migraines (Mittal et al, 2006).…”

Study on the adsorption properties of methyl orange by natural one-dimensional nano-mineral materials with different structures

“…However, the current research on the adsorption of dyes by natural nanotube minerals mainly focuses on the modification of nanotubes and the mechanism of the adsorption process 35 , 45 – 47 , but there is a lack of in-depth discussion on the influence of composition and structure on the adsorption of dyes and other pollutants. Ionic pollutants in aqueous solutions always have some kind of charge, for example, methyl orange is an anionic dye, then the charged properties of mineral surfaces in water will naturally have a great impact on the adsorption effect of ionic dyes 48 – 50 . Therefore, the surface charge of minerals is one of the main reasons that affect the adsorption of anionic dyes by minerals.…”

Easy-fabrication and low-cost carbamate-based porous organic polymers for efficient removal of methylene blue

“…Especially, due to the extremely common and cheap building blocks (MDI and PLG) as well as the simple synthesis process, the CPOPs should be much cheaper than other COFs. 48…”

“…Especially, due to the extremely common and cheap building blocks (MDI and PLG) as well as the simple synthesis process, the CPOPs should be much cheaper than other COFs. 48 Adsorption thermodynamics: effects of temperature. The influence that temperature acted on MB adsorption was studied from 25 1C to 65 1C, in aspect of certain thermodynamic parameters, like free energy, heat of adsorption and entropy.…”