Fe-functionalized walnut shell–activated carbon for the facile desulfurization of liquid fuels

• Published in: Biomass conversion and biorefinery Vol. 15; no. 5; pp. 7509 - 7522
• Main Authors: Boostani, Fatemeh, Sharififard, Hakimeh, Darvishi, Parviz, Lashanizadegan, Asghar
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.03.2025; Springer Nature B.V
• Subjects: Activated carbon; Adsorption; Biomass; Biorefineries; Biotechnology; Desulfurizing; Dibenzothiophene; Energy; Ferric chloride; Iron; Isooctane; Liquid fuels; Original Article; Renewable and Green Energy; Sulfur compounds; Sulfur removal; Walnuts; Removal; Functionalization; Walnut shell; Activated carbon; Dibenzothiophene
• ISSN: 2190-6815; 2190-6823
• DOI: 10.1007/s13399-024-05696-x

The removal of sulfur compounds from fuels is an important subject, and the adsorption desulfurization has attracted research attention in recent years. This research aims to study the adsorption ability of iron-functionalized activated carbon to desulfurize liquid fuel. Iron-functionalized activated carbon (IFAC) was synthesized from walnut shell waste via a chemical activation method using FeCl 3 as a modifier and activator agent. The synthesis and modification processes were performed in one step. Various characterization methods were used to determine the characteristics of this adsorbent. The synthesized IFAC was used to remove dibenzothiophene (DBT) from isooctane fuel. Also, to study the performance of the IFAC/DBT adsorption system, the adsorption process was done discontinuously and by studying the effect of adsorption parameters using a central composite design (CCD). According to the results of optimal conditions, when the DBT concentration is 150 mg/L, the speed of stirring is 50 rpm, and the IFAC dose is 0.05 g/L, the IFAC can eliminate 97.03% of the DBT from isooctane fuel. According to the results of kinetic and equilibrium experiments, the predominance of chemical adsorption of DBT on the activated carbon surface was demonstrated and it was also proved that the adsorption process is done in a single layer. Langmuir equilibrium isotherm data showed that the functionalized AC can adsorb 285.71 mg DBT per gram of IFAC. The results of regeneration experiments showed that the iron-functionalized activated carbon’s adsorption ability for DBT removal is decreased by 16% after four consecutive cycles. Graphical abstract