Facial synthesis of V-containing CuMgAl-LDHs as a new catalyst for the phenol hydroxylation

Abstract

• Vanadate-intercalated LDHs was prepared by ultrasonic-assisted co-precipitation method. • One step hydroxylation of phenol to catechol and hydroquinone was carried out using H 2 O 2 as oxidant and H 2 O as solvent. • Excellent conversion of 50.22% and a yield of 28.75% was obtained for vanadate-intercalated LDHs. One step liquid phase hydroxylation of phenol to catechol and hydroquinone over vanadate-intercalated Cu/Mg/Al-layered double hydroxides (LDHs) was carried out using hydrogen peroxide as an oxidant and water as a solvent. The catalyst was synthesized by ultrasonic-assisted co-precipitation and ion-exchanged method under N 2 atmosphere. Also, the catalyst was characterized by IR, XRD, TG-DTA, ICP, BET, FE-SEM, TEM, and elemental mapping analyses. The result indicated the LDHs lamellar structure and plate-like shape particles of the synthesis catalyst with good vanadate intercalation. The effect of several reaction parameters, such as the amount of catalyst, phenol: oxidant ratio, reaction temperature, and time, were studied. After modifying the reaction condition, the CuMgAl-(V) catalyst exhibited an excellent conversion of 50.22% and a yield of 28.75% with the best selectivity of 57.26% at 80 °C, 6 h, phenol: oxidant ratio = 1:1, and phenol/ catalyst molar ratio = 125.