# Reconstructing Kaolinite Compounds for Remarkably Enhanced Adsorption of Congo Red

## TL;DR

Scientists created a new kaolinite compound that can efficiently remove Congo Red dye from water, offering a promising solution for environmental cleanup.

## Contribution

The novel contribution is the reconstruction of kaolinite into γ-AlOOH@A-Kaol, which shows remarkably enhanced adsorption capacity for Congo Red dye.

## Key findings

- γ-AlOOH@A-Kaol has a sorption capacity exceeding 1000 mg/g for Congo Red dye.
- The compound's porous structure and surface hydroxyl groups contribute to its high adsorption efficiency.
- The material's surface area and pore characteristics differ significantly from the original kaolinite and γ-AlOOH.

## Abstract

Organic dyes are widely used in many important areas, but they also bring many issues for water pollution. To address the above issues, a reconstructed kaolinite hybrid compound (γ-AlOOH@A-Kaol) was obtained from raw kaolinite (Kaol) in this work. The product was then characterized by X-ray diffraction (XRD), Fourier-transform infrared (ATR-FTIR), Brunauer-Emmett-Teller (BET), and scanning electron microscopy (SEM), and the absorption properties of γ-AlOOH@A-Kaol for congo red were further studied. The results demonstrated that flower-like γ-AlOOH with nanolamellae were uniformly loaded on the surface of acid-treated Kaol with a porous structure (A-Kaol). In addition, the surface area (36.5 m2/g), pore volume (0.146 cm3/g), and pore size (13.0 nm) of γ-AlOOH@A-Kaol were different from those of A-Kaol (127.4 m2/g, 0.127 cm3/g, and 4.28 nm, respectively) and γ-AlOOH (34.1 m2/g, 0.315 cm3/g, and 21.5 nm, respectively). The unique structure could significantly enhance the sorption capacity for congo red, which could exceed 1000 mg/g. The reasons may be ascribed to the abundant groups of -OH, large specific surface area, and porous structure of γ-AlOOH@A-Kaol. This work provides an efficient route for comprehensive utilization and production of Kaol-based compound materials that could be used in the field of environmental conservation.