ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Removal of pharmaceutical compounds from aqueous solution by clay-based synthesized adsorbents: adsorption kinetics and isotherms studies

Mahdieh Azizpourian, Ghazaleh Kouchakzadeh, and Zohreh Derikvand

Department of Chemistry, Khorramabad Branch, Islamic Azad University, Khorramabad, Iran

E-mail: gh_kouchakzadeh@yahoo.com

Received: 17 December 2022  Accepted: 3 March 2023

Abstract:

The presence of pharmaceutical compounds in the environment threatens human health. The introduction of these substances into organic sources causes pollution of plants and soil and creates problems for public health. In this research, the removal of metronidazole and ibuprofen from aqueous solutions was investigated using clay nanocomposites as adsorbents. First, zero-valent iron nanoparticles (nZVIs) were synthesized, and then nZVI-clay and activated carbon-nZVI-clay nanocomposites were prepared. The characteristics of primary materials and synthesized nanocomposites were confirmed by XRD, FT-IR, and SEM techniques. Next, a certain amount of adsorbent was added to different concentrations of drugs separately, and the absorption of the solutions was detected by UV–Vis spectrophotometry at specific times. Afterward, the effects of pH (3–11), adsorbate concentration (10–50 ppm), adsorbent amount (4–12 gL⁻¹), and contact time (15–240 min) were evaluated for the removal of Metronidazole and Ibuprofen. Eventually, the adsorption isotherm and the kinetic behavior of adsorption in an aqueous solution were investigated. The results show that the nanocomposite-activated carbon-nZVI-clay with 20% activated carbon removes 87.11% metronidazole and 87.1% ibuprofen from an aqueous solution at 150 min. The adsorption of drugs on nanocomposites well followed Langmuir adsorption isotherm and pseudo-second-order kinetic model. Overall, it can be concluded that nanotechnology, with the help of natural adsorbents, can offer new solutions in wastewater treatment.

Keywords: Fe0 nanoparticles; Clay; Metronidazole; Ibuprofen; Adsorption

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-02774-8

Chemical Papers 77 (8) 4245–4264 (2023)