Application of Parallel Difference Tests to Resolve the Axial Activation–Deactivation Profile of Copper–Zinc Oxide Catalyst During Hydrogenation of Methyl Acetate

The deactivation of a copper–zinc oxide catalyst has been studied in a set of parallel tests which covered a range of space-times with equal flow and variable catalyst quantity, from 1/8th bed to full bed. The activation–deactivation trends over time in different segments of the full catalyst bed have been determined by two alternative parallel difference methods. The relative trends in segmental activity over time were followed by (a) using a pre-determined reaction model, and (b) by referencing the axial conversion profile against the initial profile. The trends estimated by both methods were in broad agreement. The results show that the front segment of the catalyst bed experienced a more rapid process of deactivation than the rest of the catalyst bed. This process is consistent with the known susceptibility of this type of catalyst to deactivation by chlorine and sulfur impurities in the feedstock. The main part of the catalyst bed appeared to undergo a process of activation during the first 150 h, followed by a slow process of deactivation which was more rapid during periods at increased temperature. The slow deactivation is most likely associated with sintering of copper particles. The conversion parallel difference method provides a convenient and rapid tool for segmental analysis of parallel life tests, and is well-suited to resolving the impact of a poison front within a catalyst bed.

Copper–zinc oxide heterojunction catalysts exhibiting enhanced photocatalytic activity prepared by a hybrid deposition method

Hybrid synthesis of Cu2O/ZnO nanorod heterojunction exhibiting enhanced interfacial charge transfer and photocatalytic activity comprising hydrothermal synthesis step of ZnO nanorods followed by advanced gas deposition of Cu nanoparticles.

Correction: Copper–zinc oxide heterojunction catalysts exhibiting enhanced photocatalytic activity prepared by a hybrid deposition method

Correction for ‘Copper–zinc oxide heterojunction catalysts exhibiting enhanced photocatalytic activity prepared by a hybrid deposition method’ by José Montero et al., RSC Adv., 2021, 11, 10224–10234, DOI: 10.1039/D1RA00691F.

Surface Modification of Bacterial Cellulose by Copper and Zinc Oxide Sputter Coating for UV-Resistance/Antistatic/Antibacterial Characteristics

In our study, the surface of bacterial cellulose was successively modified by copper and zinc oxide nanoparticles using direct current (DC) magnetron sputtering and radio frequency (RF) reactive sputter coating techniques. The target materials, copper and zinc, were 99.99% pure and used in the presence of argon (Ar) gas, while zinc nanoparticles were sputtered in the presence of oxygen gas to make zinc oxide nanoparticles. The as-prepared bacterial cellulose/copper/zinc oxide nanocomposite has good ultraviolet resistance, anti-static and antibacterial characteristics. The surface morphology and chemical composition of the nanocomposite were examined by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopic (EDS) techniques. The prepared bacterial cellulose/copper/zinc oxide nanocomposite illustrates excellent ultraviolet resistance (T.UVA%; 0.16 ± 0.02, T.UVB%; 0.07 ± 0.01, ultraviolet protection factor (UPF); 1850.33 ± 2.12), antistatic behavior (S.H.P; 51.50 ± 4.10, I.E. V; 349.33 ± 6.02) and antibacterial behavior (Escherichia coli; 98.45%, Staphylococcus aureus; 98.11%). Our nanocomposite prepared by sputter coating method could be a promising and effective candidate for ultraviolet resistance, antistatic and antibacterial in term of functional, technical, medical and in many daily life applications.