CuAPO-5 as a Multiphase Catalyst for Synthesis of Verbenone from α-Pinene

Abstract

Copper(II)-containing aluminum phosphate material (CuAPO-5) was synthesized hydrothermally and used as a multiphase catalyst for the oxidation of α-pinene to verbenone. The catalysts were analyzed using X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area techniques, X-ray photoelectron spectroscopy (XPS), and ammonia temperature programmed reduction (NH3-TPD). Scanning electron microscopy (SEM), X-ray energy spectrometry (EDS), inductively coupled plasma emission spectroscopy (ICP-OES), Fourier infrared spectroscopy (FT-IR), and ultraviolet-visible spectroscopy (UV-vis) were performed to characterize the material. The effects of reaction temperature, reaction time, n(α-pinene)/n(TBHP), and solvent on the catalytic performance of CuAPO-5 were investigated. The results show that all the prepared catalysts have AFI topology and a large specific surface area. Copper is evenly distributed in the skeleton in a bivalent form. The introduction of copper increases the acid content of the catalyst. Under the optimized reaction conditions, 96.8% conversion of α-pinene and 46.4% selectivity to verbenone were achieved by CuAPO-5(0.06) molecular sieve within a reaction time of 12 h. CuAPO-5(0.06) can be recycled for five cycles without losing the conversion of α-pinene and the selectivity to verbenone.

Development of a chromium oxide loaded mesoporous silica as an efficient catalyst for carbon dioxide-free production of ethylene oxide

“…[7][8][9] In this pursuit, prior investigations have focused on catalysts composed of transition metals in higher oxidation states, which are supported on mesoporous silica materials (MSM), particularly MCM-41 and SBA-15. [10][11][12][13][14] It was noted that the alkene substrate underwent catalysis through a redox reaction, enabling the transfer of oxygen from the oxidant to the alkene double bond. [15][16][17][18][19] Among the various metal options for effective catalysts, niobium (Nb)-based catalysts have demonstrated good catalytic activity in the epoxidation of cyclic alkenes, propene, and various chemical substrates like carvone and limonene.…”

A New Mixed-Metal Phosphate as an Efficient Heterogeneous Catalyst for Knoevenagel Condensation Reaction

“…Over the past few years, significant strides have been made in the synthesis and characterization of porous metal phosphates. Advanced techniques, including solvothermal and hydrothermal methods [34,35], have been harnessed to produce materials with well-defined porosity and desirable properties. Moreover, researchers have focused their efforts on designing and modifying these materials to enhance their performance and expand their potential applications.…”