Vapor Phase Alkylation of Isomeric Cresols with Tert-Butyl Alcohol over Perlite Supported Sulfated Zirconia Catalyst

Abstract

In the present study, perlite was thermally activated and then modified desirably to generate super acidity by loading different weight percentages of sulfated zirconia (SZ) via the two-step sol-gel method. As-prepared sulfated zirconia perlite (SZP) catalysts showed suitable catalytic potential in the vapor phase alkylation of o, m, and p-cresols with tert-butyl alcohol. The presence of crystalline phases in SZP catalysts was confirmed by XRD and FT-IR studies. TEM images revealed the nano size of the catalysts in the range of 9–25 nm. The presence of SZ on the surface of perlite was further confirmed by N2 adsorption–desorption, SEM, SEM-EDX, TGA, and UV-Vis DRS techniques. The pyridine FT-IR results confirmed the existence of Brønsted, Lewis acidic sites and their combination as super acidic catalytic active centers on the surface of catalyst utilized in the vapor phase alkylation of o, m, and p-cresols with tert-butyl alcohol. The regeneration and reusability of the preferred catalyst until the 5th reaction cycle without any considerable loss in catalytic activity demonstrated the stability of the catalyst. Comparative studies show that SZP can be regenerated and is superior compared to other catalysts previously used for other alkylation reactions with the potential for use on a large scale.

Structural Characterization of Composites Based on Butadiene Rubber and Expanded Perlite

“…Figure 7 shows the UV-Vis spectra of EP and PhEP (a), EP/PhBR and PhEP/PhBR composites (b), and PhBR (c). In the UV-Vis spectra of both EP and PhEP samples, peaks characteristic of aluminosilicates and explaining the presence of silica were observed at wavelengths of 254 nm and 243 nm, respectively [25]. As can be seen from Figure 7a, after the OxCh reaction of EP, the observed peak at 254 nm shifted to lower wavelengths (243 nm), and visible-light absorption improved.…”

Nanosized Silica-Supported 12-Tungstophosphoric Acid: A Highly Active and Stable Catalyst for the Alkylation of p-Cresol with tert-Butanol

“…The % selectivity of 2-TBC increased when the molar ratio increased from 1 to 2, and this increase became negligible afterwards. The % selectivity of 2,6-DTBC increased when increasing the concentration of tert-butyl alcohol due to the greater resident time of the mono tert-butylated product on the catalyst surface [33]. As the conversion of p-cresol and the selectivity toward 2-TBC are higher at a molar ratio of p-cresol to tertiary butanol of 1:2, the optimum molar ratio was fixed at 1:2.…”

“…Sarish et al studied the alkylation of p-cresol with tertbutanol over WOx/ZrO 2 catalysts and the corresponding catalytic activity, which was compared with sulfated zirconia and zeolites like USY, H, and montmorillonite K-10, under optimized reaction conditions and concluded that the activity of sulfated zirconia was lower than that of the WO 3 /ZrO 2 catalyst [32]. Malpani et al designed a perlite-supported sulfated zirconia catalyst for the alkylation of isomeric cresols with tert-butyl alcohol, and the study revealed better conversion with few limitations [33].…”

Synthesis of hierarchical ZSM‐5 using polymer macro template for selective C‐alkylation of m‐cresol with tert‐butanol

“…[9][10][11][12][13][14][15] Heterogeneous solid acids comprising diverse materials have been reported in the recent past for the production of tert-butylate m-cresol. Materials based on sulphated zirconia, 16 Al-MCM-41 molecular sieves, 17 Supported 12-tungstophosphoricacid and 12-tungstosilicicacid, 18 Perlite Supported Sulfated Zirconia, 19 12-tungstophosphoricacid and 12-tungstosilicicacid supported onto neutral alumina 20 are reported in the literature.…”