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

Phase inversion synthesis of Fe/chitosan-bentonite beads for H₂S adsorptive removal

Nguyen Manh Hung, Nguyen Thi Truc Phuong, Nguyen Tan Phat, Nguyen Van Dung, Ngo Tran Hoang Duong, Tran Thuy Tuyet Mai, and Nguyen Quang Long

Faculty of Chemical Engineering, Ho Chi Minh City University of Technology (HCMUT), Ho Chi Minh City, Vietnam

E-mail: nqlong@hcmut.edu.vn

Received: 9 October 2024  Accepted: 5 February 2025

Abstract:

In this study, the bead-like Fe/chitosan-bentonite adsorbents were prepared from a combination of bentonite and chitosan by phase inversion, followed by different quantities of iron immersion to remove hydrogen sulfide (H₂S). The beads have been characterized using advanced methods including SEM, EDS, XRD, FTIR, nitrogen adsorption isotherms, and mechanical strength. The H₂S removal efficiency of the material was investigated in the continuous fixed-bed column system under various temperature conditions, different dosages of used materials, and varying H₂S concentrations in the gas stream, to assess its potential for biogas purification. The results indicated that the adsorption capacity of Fe/chitosan-bentonite beads impregnated with 0.09 M FeCl₃.6H₂O solution gradually increased with increasing these parameters and reached the highest of 24.4 mg_H₂S/g_materials at conditions of 30 °C, 0.3 g of adsorbents, and 1100 ppm H₂S. Moreover, two procedures used to evaluate the material's regeneration ability include blowing air through the materials and exposing them to air after the samples adsorbed H₂S. As a result, this material can achieve over 90% regeneration after 12 h of continuous air blowing or exposure to air, demonstrating its sustainable application.

Graphical abstract

Keywords: Chemical hydrogen storage; Hydrogen storage materials; Hydrogen storage; Inorganic Chemistry; Underground hydrogen storage; Zeolites; Chitosan-bentonite; Immersion; Phase inversion; H2S removal; Bead-like materials

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04024-5

Chemical Papers 79 (6) 3695–3708 (2025)