Ultra-efficient adsorption of copper ions in chitosan–montmorillonite composite aerogel at wastewater treatment

The montmorillonite (MMT) slurry is modified by cation exchange to create modified montmorillonite with a two-dimensional network structure. The addition of chitosan (CS) cross-links the two-dimensional sheets to build a three-dimensional network structure with a high specific surface area. The modified montmorillonite-based aerogel prepared in this work is a better water treatment material. This new type of aerogel can efficiently adsorb copper ions in wastewater. The structure and performance of the composite material were characterized in this article. Besides, this article focuses on the study of adsorption kinetics, adsorption thermodynamics, pH effect, and recycling performance. The adsorption equilibrium time of CS–MMT2 was 50 min. The removal rate of Cu²⁺ was as high as 98.21%. The maximum adsorption capacity was 86.95 mg/g. The adsorption process of Cu²⁺ by CS–MMT composite aerogel conformed to the quasi-second-order kinetic model and the Langrangian adsorption isotherm. After 7 cycles, the removal rate of Cu²⁺ by CS–MMT2 remained above 85%. This article also involves the discussion of the material's adsorption mechanism for Cu²⁺. This is a kind of environmentally friendly material that can be mass-produced, cheap, efficient, and excellent, which is of great significance to the development of environmental protection.