Preparation and Characterization of Fe₃O₄ Nanoparticles/Sulfonated Natural Zeolite as a Catalyst for the Esterification of Glycerol to Triacetin

Dewi Rachmawati, Didik Krisdiyanto

Uin Sunan Kalijaga Yogyakarta

Research has been conducted on the preparation and characterization of sulfonated Fe3O4/zeolite nanoparticles as catalysts in the esterification reaction of glycerol to triacetin. This research aims to characterize Fe3O4 nanoparticles/sulfonated natural zeolite catalyst using FTIR, XRD, and gravimetric method acidity test (ammonia vapor adsorption) and study the effect of catalyst mass variation and reaction time on the selectivity value of triacetin in the esterification reaction of glycerol with acetic acid anhydride. The preparation of Fe3O4 nanoparticles/sulfonated natural zeolite was carried out through three steps, namely preparation of natural zeolite, activation of sulfonated zeolite and Fe3O4 loading on sulfonated zeolite by coprecipitation. Furthermore, the catalyst was tested for its catalytic activity in the esterification reaction of glycerol with acetic acid anhydride to triacetin at mass variations of 3%, 5%, and 7% for time variations of 30, 45, 60, 75, and 90 minutes. The results of characterization using FTIR showed the presence of four main absorption bands namely 1049.28; 1219.01; 794.67; and 447.49 cm-1 for sulfonated natural zeolite and 570.93 cm-1 for magnetite Fe-O bond. Characterization results using XRD showed that sulfonated natural zeolite was dominated by mordenite mineral at 2θ = 10.22o; 20.15o and 22.88o and confirmed the presence of Fe3O4 compound at 2θ = 30.58o; 35.96o; 43.81o; 53.08o; 57.6o and 63.26o with cubic crystallographic plane. The results of the gravimetric method acidity test showed that the Fe3O4 compound loading on sulfonated natural zeolite decreased the total acidity value. The catalyst activity test in the esterification reaction of glycerol with acetic acid anhydride provided information that the trend of triacetin selectivity value tends to increase along with the increase in catalyst mass and reaction time.