Characterization and catalytic performance of basaltic dust as an efficient catalyst in the liquid‐phase esterification of acetic acid with n‐butanol

Abstract

Three natural basaltic samples were collected and used as efficient catalysts for the liquid‐phase synthesis of n‐butyl acetate. The samples were characterized by X‐ray fluorescence analysis (XRF), X‐ray diffraction (XRD), thermogravimetry (TG), differential thermal analysis (DTA), Fourier transform infrared (FT‐IR), scanning electron microscopy (SEM), and N2 sorption. The acidity of the samples was determined using isopropanol dehydration, and the strength of the acid sites was measured using chemisorption of basic probes. The catalytic activity of the samples towards the esterification of acetic acid with n‐butanol was extensively examined. The influence of different parameters, such as the reaction refluxing time, molar ratio, catalyst loading, reusability, and calcination temperature, on the esterification reaction was studied in detail. The results revealed that all samples had high catalytic activity with a selectivity of 100% to n‐butyl acetate formation. In addition, the sample obtained from the top hill of Volcano had the highest activity with a 80% yield of n‐butyl acetate. Moreover, the significant catalytic performances were well correlated with the acidity of the samples and to the reaction rate constants.

Green synthesis of bio‐ethyl acetate over Egyptian natural red clay as a highly active, selective, and eco‐friendly catalyst

“…As that previously reported in the literature “acidity is an important catalyst property and ultimately has a significant impact on the activity in the esterification reaction. Natural clay minerals and other aluminosilicates, like no other materials, comprise both BrØnsted and Lewis basic sites.” The acidity of aluminosilicates is usually determined using the probe molecules.…”

“…The acidity of ERC catalysts was investigated by studying the chemisorption of PY, DMPY, and the dehydration of IPA as described by Said et al In these procedures “dehydration of IPA was carried out in a conventional fixed‐bed flow reactor, nitrogen used as a carrier gas. The reaction conditions were: 1 g catalyst weight, 2 vol% IPA in the gas feed, 130 cm 3 /min total flow rate, and 225°C reaction temperature.…”

“…However, “the ability of the ERC catalyst to break the O–H bond during the chemisorption itself by polarizing the C–O bond and leaving O–H bond in contact may be important in catalyzing the dehydration reaction. This facilitated by the presence of acidic groups . In agreement with such a suggestion, Okuhara et al reported that, the catalytic formation of ethylene from ethanol requires fission of the C–O bond on the B acid sites.…”

Positron Annihilation Spectroscopy of Basaltic Rocks from Plio-Qaternary Volcanics, Sana’a-Amran Volcanic Field, Yemen

“…The energy calibration for the spectrometer was ~68 eV/channel obtained using 133 Ba source. A positron source with an activity of 0.5 µCi 22 Na was used, which prepared using a droplet of 22 NaCl solution was dried onto two identical Kapton foils (7.5 µm thick). Two disk samples were arranged with the 22 Na source in a 4π configuration.…”

New Application of Highly Vesicular Basalt from Jabel Isbil Volcano (Dhamar-Rada'a Volcanic Field), Yemen

“…Recently, Said et al, studied the same samples of Isbil Volcano on the basis of chemical reactions and their catalysis. They exhibited that these samples, in particular, vesicular basalt, giving rise to an excellent natural catalysis in some chemical reactions [6].…”