Acidic modification of natural stone for Remazol Black B dye adsorption from aqueous solution- central composite design (CCD) and response surface methodology (RSM)

Hamed Soleimani; Kiomars Sharafi; Jafar Amiri Parian; Jalil Jaafari; Gholamreza Ebrahimzadeh

doi:10.1016/j.heliyon.2023.e14743

Acidic modification of natural stone for Remazol Black B dye adsorption from aqueous solution- central composite design (CCD) and response surface methodology (RSM)

Heliyon. 2023 Mar 22;9(4):e14743. doi: 10.1016/j.heliyon.2023.e14743. eCollection 2023 Apr.

Authors

Hamed Soleimani^{1

2}, Kiomars Sharafi^{1

3}, Jafar Amiri Parian⁴, Jalil Jaafari⁵, Gholamreza Ebrahimzadeh⁶

Affiliations

¹ Research Center for Environmental Determinants of Health (RCEDH), Research Institute for Health, Kermanshah University of Medical Sciences, Kermanshah, Iran.
² Student's Scientific Research Center, Tehran University of Medical Sciences, Tehran, Iran.
³ Department of Environmental Health Engineering, School of Public Health, Kermanshah University of Medical Sciences, Kermanshah, Iran.
⁴ Biosystems Engineering Department, Bu-Ali Sina University, Hamedan, Iran.
⁵ Department of Environmental Health Engineering, Research Center of Health and Environment, School of Health, Guilan University of Medical Sciences, Rasht, Iran.
⁶ Department of Environmental Health Engineering, School of Public Health, Zabol University of Medical Sciences, Zabol, Iran.

Abstract

This study investigated the adsorption capacity of Remazol Black B (RBB) from aqueous solutions using a pumice stone as a cheap, high-frequent, and available adsorbent. The raw pumice was modified using five acids: Acetic, Sulfuric, Phosphoric, Nitric, and Hydrochloric acid. Fourier transform infrared spectrograph (FTIR), x-ray fluorescence (XRF), and scanning electron microscopy (SEM) were used to analyze the morphological and chemical properties of raw and modified adsorbents. The adsorption capacity equilibrium was investigated using the Langmuir, Freundlich, Temkin, and Dubinin - Radushkevich isotherms. The results indicated that the data are well-fitted with Langmuir isotherm. The maximum adsorption capacity was observed when pumice modified with H₂SO₄ (q_m = 10.00 mg/g) was used, and the RBB removal efficiency was higher than that for raw pumice (q_m = 5.26 mg/g). Also, the results were best fitted with pseudo-second-order kinetic. The experiments indicated that increasing the RBB concentration reduces the efficiency of adsorbents while increasing the contact time and adsorbent doses improved the RBB removal efficiency. Accordingly, it can be concluded that pumice stone modified with various acids can be considered a cheap adsorbent with high efficiency in removing RBB from industry effluent.

Keywords: Adsorption; Natural adsorbents; Pumice stone; Remazol Black B (RBB); Response surface methodology.