Work

Convenient preparation of spongy chitosan composite of metal-organic framework with high adsorption for dyes or metal ions

Year: 2026

Type: article

Abstract: This study incorporated typical metal-organic frameworks (MOFs, MIL-68(Al)) into low-cost chitosan matrix via cross-linking and freeze-drying for the convenient pollutant removal. An environmentally friendly composite aerogel composed of chitosan and MIL-68(Al) (with a mass ratio of 10:1, denoted as CS10/MIL-68(Al)) was prepared under mild conditions, achieving a density of 0.013 g/cm3. Meanwhile, the adsorbents with spongy form overcome the disadvantage of poor recyclability and complex operational process compared with powder form of MOFs. The spongy aerogel materials were characterized by FT-IR, XRD, XPS, SEM, and other methods. Moreover, the structure of this material remains stable before and after adsorption, and can be directly extracted from the solution using forceps after adsorption. What is more, adsorption of methyl orange (MO) equilibrium was achieved within 10 minutes, with a maximum capacity of 496.72 mg/g of solution. It has been demonstrated that, after four regeneration cycles, the removal efficiency remains above 50%. Density functional theory (DFT) calculations were employed to analyze the adsorption energy profiles between CS10/MIL-68(Al) and primary adsorption sites of MO, thereby revealing the optimal adsorption configuration. Moreover, various pollutants and metal ions can be effectively degraded. Mechanistic studies have revealed that the rapid adsorption process is driven by electrostatic attraction, π-π stacking, hydrogen bonding, and coordination interactions. This work presents a quick and straightforward method of synthesising a adsorbent, demonstrating its potential for treating wastewater contaminated with MO and other contaminants in industrial.

Source: Results in Engineering

DOI: 10.1016/j.rineng.2026.109767