Development of a Citric-Acid-Modified Cellulose Adsorbent Derived from Moringa peregrina Leaf for Adsorptive Removal of Citalopram HBr in Aqueous Solutions

Syed Najmul Hejaz Azmi; Wafa Mustafa Al Lawati; Umaima Hamed Abdullah Al Hoqani; Ekhlas Al Aufi; Khalsa Al Hatmi; Jumana Salim Al Zadjali; Nafisur Rahman; Mohd Nasir; Habibur Rahman; Shah A Khan

doi:10.3390/ph15060760

Development of a Citric-Acid-Modified Cellulose Adsorbent Derived from Moringa peregrina Leaf for Adsorptive Removal of Citalopram HBr in Aqueous Solutions

Pharmaceuticals (Basel). 2022 Jun 17;15(6):760. doi: 10.3390/ph15060760.

Affiliations

¹ Applied Sciences Department (Chemistry Section), Higher College of Technology, University of Technology and Applied Sciences, Al-Khuwair 133, Muscat P.O. Box 74, Oman.
² Applied Sciences Department (Biology Section), Higher College of Technology, University of Technology and Applied Sciences, Al-Khuwair 133, Muscat P.O. Box 74, Oman.
³ Department of Chemistry, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India.
⁴ Department of General Studies, Jubail Industrial College, P.O. Box 10099, Jubail Industrial City 31961, Saudi Arabia.
⁵ Department of Pharmaceutical Chemistry, College of Pharmacy, National University of Science and Technology, PC 130, Muscat P.O. Box 620, Oman.

Abstract

A citric-acid-modified Moringa peregrina leaf substrate was prepared and studied as an effective adsorbent for the adsorptive removal of citalopram HBr (CTM). FTIR spectra were utilized to characterize the prepared solid. The effects of experimental variables on the percentage removal of citalopram HBr were investigated using response surface methodology. The optimum conditions selected for removal of CTM were 7 and 4 min, 0.17 g per 50 mL and 35 mg·L^-1 for pH, contact time, adsorbent dose and initial concentration of CTM, respectively. Under the optimized experimental conditions, 82.59% CTM (35 mg·L^-1) was removed. The Langmuir isotherm, Freundlich isotherm, pseudo second-order kinetic model and diffusion-chemisorption model explained the adsorption data successfully. The maximum adsorption capacity at 298 K was 8.58 mg·g^-1. A thermodynamic study illustrated that CTM adsorption was spontaneous and endothermic in nature.

Keywords: Freundlich isotherm; Langmuir isotherm; Moringa peregrina leaf; adsorbent; citalopram HBr; citric acid.

Grants and funding

This research was funded by The Research Council (a part of MOHERI), Sultanate of Oman (BFP/URG/CBS/19/042).