# Preparation of Magnetic Carbon Composite from Waste Amine-Oxime Resin and Its Adsorption Properties for Chromium

## TL;DR

This paper describes converting waste resin into a magnetic material that effectively removes chromium from water.

## Contribution

The novel contribution is converting waste amidoxime resin into a magnetic carbon composite for efficient Cr(VI) adsorption.

## Key findings

- The magnetic composite achieved a maximum Cr(VI) adsorption capacity of 197.63 mg/g under optimized conditions.
- The adsorption process followed pseudo-second-order kinetics and Langmuir isotherm models with high correlation coefficients.
- Functional groups like -C=O, C-O, and Fe-O were confirmed to play a key role in Cr(VI) adsorption via FTIR and XPS spectroscopy.

## Abstract

A waste amidoxime chelate resin (WAR) was converted into a magnetic composite adsorbent (MCA) via carbonization and magnetization for the effective removal of Cr(VI). Under optimized conditions (pH = 1, 30 °C, 1 h), the adsorbent achieved a maximum Cr(VI) adsorption capacity of 197.63 mg/g. The adsorption process conformed to the pseudo-second-order kinetic model (R2 > 0.98) and Langmuir isotherm model (R2 > 0.99). The materials can be separated by magnetism. The primary mechanism for the adsorption of Cr(VI) involved monolayer chemisorption. FTIR spectroscopy confirmed the dominant role of -C=O, C-O, and Fe-O in the adsorption process. XPS spectroscopy confirmed the dominant role of -C=O and C-O in the adsorption process. The successful conversion of the WAR into an MCA not only mitigates waste accumulation but also provides a cost-effective strategy for heavy metal remediation.