Fast Adsorption of Crystal Violet on Polyacrylic Acid‐Bound Magnetic Nanoparticles

Abstract

The adsorption of crystal violet from an aqueous solution by polyacrylic acid‐bound magnetic nanoparticles was studied. It was shown that the magnetic nano‐adsorbent was quite efficient for the adsorption/desorption of crystal violet. In the aqueous solution of crystal violet at 25°C, the adsorption behavior followed the Langmuir adsorption isotherm with a maximum adsorption amount of 116 mg g⁻¹ and a Langmuir adsorption equilibrium constant of 0.005 L mg⁻¹. In the methanol solution of acetic acid (1.0–8.0%), desorption of crystal violet increased up to 100% with increasing the acetic acid concentration. The reusability of magnetic nano‐adsorbent and the effects of temperature, pH, and phosphate on the adsorption of crystal violet were also investigated. Additionally, it was very noteworthy that the adsorption/desorption rate of crystal violet was quite fast (required time < 1 min) due to the absence of pore‐diffusion resistance. The developed magnetic nano‐adsorbent will be useful in the removal of cationic dyes from wastewater.

Keywords:

• Adsorption
• Polyacrylic acid
• Crystal violet
• Magnetic nanoparticles
• Nano

Acknowledgments

This work was performed under the auspices of the National Science Council of the Republic of China, under contract number NSC90‐2214‐E006‐009, for which the authors wish to express their thanks.