Wet oxidation

About: Wet oxidation is a research topic. Over the lifetime, 3094 publications have been published within this topic receiving 61536 citations.

Ruthenium nanoparticles supported on nitrogen-doped carbon nanofibers for the catalytic wet air oxidation of phenol

Abstract: The effect of nitrogen content in N-doped carbon nanofibers (N-CNFs) on the catalytic activity of Ru/N-CNFs in the wet air oxidation of phenol has been studied. The N-CNFs, irrespective of nitrogen content and Sibunit, are shown to be low active. In the case of Ru-containing catalysts, nitrogen in N-CNFs was found to be responsible for both the increased activity and stability of the catalysts toward deactivation. The XPS showed the formation of carbon-oxygen structures with hydroxyl (carbonyl) end groups blocking ruthenium on the surface of the catalysts without nitrogen. For the catalysts with nitrogen, the ruthenium nanoparticles were not blocked in the course of the reaction and mainly the carboxyl (carbonate) surface groups were formed. The nature of this effect is discussed.

Copper/MCM-41 as catalyst for the wet oxidation of phenol

Abstract: A heterogeneous copper catalyst supported on mesoporous MCM-41 was developed. The parent MCM-41 has a large pore area of over 1400 m(2)/g. Copper was chosen as the active element of catalyst and loaded into MCM-41 by adsorption at ambient temperature. The prepared catalysts were evaluated in the catalytic wet oxidation of phenol solution with an initial concentration of 1,300 ppm at 150 and 200 degreesC. The catalyst was found to be of high catalytic activity. It is also shown that the catalyst with a higher copper loading exhibits higher ability of accelerating the catalytic reaction to certain extent but reaches its constant level afterwards. (C) 2001 Elsevier Science B.V. All rights reserved.

Synthesis, characterization and catalytic application for wet oxidation of phenol of iron-containing clays

Abstract: High-surface-area pillared clays (PILC) were prepared from naturally occurring montmorillonites by exchanging interlayer ions to polyoxocations containing (i) aluminum (Al13-PILC), (ii) iron adsorpted onto Al13-PILC, and (iii) iron and aluminum located within the same complex (Fe0.8Al12.2-PILC). The obtained Fe0.8Al12.2-PILCs were characterized by DR–UV–vis and IR spectroscopy, XRD, ESR, scanning electron microscopy and low temperature N2 adsorption measurements. Important factors affecting catalyst activity and phenol removal efficiencies have been studied, i.e. the effect of pH, temperature, catalyst concentration and stability of the catalyst.

Highly active N-doped carbon nanotubes prepared by an easy ball milling method for advanced oxidation processes

Abstract: The performance of novel N-doped carbon materials prepared by an easy ball milling method was evaluated in two distinct advanced oxidation processes (AOPs): catalytic wet air oxidation (CWAO) and catalytic ozonation (COZ), using oxalic acid as model pollutant. The ball milling method allows the incorporation of large amounts of N-groups onto the surface of carbon nanotubes, namely pyridine-like N atoms (N-6), pyrrole-like N atoms (N-5) and quaternary nitrogen (N-Q), resulting in highly active catalysts for the oxidation of oxalic acid by both AOPs. The material prepared by ball milling with melamine without solvent is the most promising sample, combining an easy preparation with high amount of N-functionalities. Under the operation conditions used, oxalic acid was completely mineralized in 5 min by CWAO and in 4 h by COZ. The novel metal-free catalyst developed by this easy ball milling method demonstrated to be effective, confirming that this solvent-free methodology is quite adequate for the preparation of N-doped carbon materials with enhanced properties for the mineralization of organic pollutants by the studied processes.