Response Surface Methodology Optimization of Friedel-Crafts Acylation Using Phosphotungstic Acid Encapsulation in a...

The present study aims at investigating the performance of Friedel-Crafts acylation of phenols and acyl chlorides over the PTA@MIL-53 (Fe) catalyst (phosphotungstic acid encapsulated in MIL-53 (Fe) via the one-pot method) under ultrasound irradiation. PTA@MIL-53 (Fe) was synthesized using ultrasound irradiation at ambient temperature and pressure. Moreover, X-ray diffraction, energy-dispersive X-ray, Fourier transform infrared, scanning electron microscopy, N₂ physisorption, and inductively coupled plasma optical emission spectrometry characterization analyses were performed to characterize the prepared composite. The reactions took place under an ultrasonic environment at ambient temperature and pressure. The obtained results reveal that the synthesized catalyst is efficient in an ultrasound irradiation environment for Friedel-Crafts reactions. The regeneration experiments indicated no significant change in the catalyst performance even after being reused for five times. Furthermore, the response surface methodology was applied to find the relationships between some specific variables and para-hydroxy acetophenone yield as a response. Finally, the results were validated with the experimental data, with which the model results were in good agreement.