Platinum catalysed wet oxidation of phenol in a stirred slurry reactor

Masende, Zpg; Kuster, Bfm Ben; Ptasinski, KJ Krzysztof; Janssen, F.J.J.G.; Katima, J.H.Y.; Schouten, JC Jaap

doi:10.1016/s0926-3373(02)00164-9

Cited by 41 publications

(23 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…To take into account effects like surface over-oxidation of platinum [29,30], leaching, platinum particle growth, and site coverage [31], an empirical deactivation function a, defined as the fraction of nondeactivated sites [32,33] can be considered. In this respect, some authors claim that over-oxidation is a slow and reversible process that occurs under oxidation conditions [34,35], which can be described by a reversible transformation of oxygen adatoms into inactive subsurface oxygen [34].…”

Section: Cwao Experimentsmentioning

confidence: 99%

Carbon supported platinum catalysts for catalytic wet air oxidation of refractory carboxylic acids

et al. 2005

View full text Add to dashboard Cite

Carbon supported platinum (1% wt) catalysts were prepared by the incipient wetness impregnation method and by organometallic chemical vapor deposition. Catalyst characterization was carried out by means of adsorption and thermogravimetric techniques, and by electron microscopy. The catalyst with higher metal dispersion was produced by incipient wetness impregnation. The catalysts were tested in the catalytic wet air oxidation (200°C and 6.9 bar of oxygen partial pressure) of aqueous solutions containing low molecular weight (C 2 to C 4 ) carboxylic acids. Significant conversions (greater than 60% over 2 h) and 100% selectivity towards water and non-carboxylic acid products were observed for both systems. The initial reaction rate was used to compare the performance of the two catalytic materials and direct correspondence to the metal dispersion was found. No metal leaching was observed during reaction and no significant deactivation occurred in three successive catalytic oxidation runs. A kinetic model based on the Langmuir-Hinshelwood formulation was applied and the results were analyzed in terms of a heterogeneously catalyzed free radical mechanism.KEY WORDS: catalytic wet air oxidation (CWAO); carbon supported platinum catalysts; incipient wetness impregnation; organometallic chemical vapor deposition (OMCVD)

show abstract

Section: Cwao Experimentsmentioning

confidence: 99%

Carbon supported platinum catalysts for catalytic wet air oxidation of refractory carboxylic acids

et al. 2005

View full text Add to dashboard Cite

show abstract

“…Examples of these processes include friction retard paper feeding (Fowlkes & Creveling, 1995;Samuel & LaValle, 1990), sheet metal stamping (Doolan et al 2001;Herron et al, 1998), injection molding (Krehwinkel & Schneider, 1988), wave soldering (Bechet et al, 1990), batch processing (Samsatli et al, 2001), thermonuclear fusion (Pacher et al, 1999), coal milling (Arauzo & Cortés, 1995), blast furnace combustion ("Aerodynamic Control of the Blast Furnace," 1981) and wastewater treatment (Masende et al, 2003;Smith et al, 1997). In each case, use of the concept as a performance optimization tool has involved the experimental determination of the upper and lower operational limits for critical engineered variables between which the performance of a functional parameter is optimized.…”

Section: Operating Windows As a Performance Optimization Toolmentioning

confidence: 99%

“…For example, Herron et al (1998) defined the operating window for an automotive sheet pressing process by experimentally determining the ranges for three critical engineered variables (punch speed, corner pres-sure, and shut height) within which maximum quality steel panels could be produced. Similarly, Masende et al (2003) determined the operating window for a catalytic wet oxidation wastewater treatment process through experimental determination of the ranges for a wide variety of critical variables within which the maximum removal of phenol from wastewater could be achieved. Use of the operating window concept as a performance optimization tool for engineered processes has proven to be very successful.This is illustrated by Bechet et al (1990), who reported a 58 percent reduction in wave soldering process failure through application of the operating window concept, resulting in the elimination of 8,190 rework hours and their associated costs.…”

Section: Operating Windows As a Performance Optimization Toolmentioning

confidence: 99%

Application of the operating window concept to remediation‐option selection

Scott

Nathanail

2004

Remediation Journal

View full text Add to dashboard Cite

tion-option operating windows involves: 1) the determination of relationships between site conditions ("critical variables") and option performance parameters (e.g., contaminant degradation or removal rates) and 2) the identification of upper-and lower-limit values ("operational limits") for these variables that define the ranges of site conditions over which option performance is likely to be sufficient (the "operating window") and insufficient (the "operating wall") for manag

show abstract

“…The process of phenol hydroxylation with 30% H 2 O 2 could be a useful process in the future because of its simplicity and lack of pollution. Redox molecular sieves, which are promising materials for transformations of large organic molecules in liquid phase reactions, have emerged recently by incorporating various transition metal species such as platinum and iron (Kannan et al, 2005;Choi et al, 2006;Kuznetsova et al, 2005;Masende et al, 2006). In this work, the catalysts consisting of bimetallic platinum/iron supported on RH-AlMCM-41 were tested for the hydroxylation of phenol.…”

Section: Introductionmentioning

confidence: 99%

Characterization of AlMCM-41 synthesized with rice husk silica and utilization as supports for platinumiron catalysts

Chumee

Grisdanurak

Neramittagapong

et al. 2009

Braz. J. Chem. Eng.

View full text Add to dashboard Cite

-RH-MCM-41 was synthesized by using silica from rice husk and further modified to increase acidity by adding Al with grafting method with Si/Al ratio of 75 and 25. The resulting materials were referred to as RH-AlMCM-41(75) and RH-AlMCM-41(25). The XRD spectra of all RH-AlMCM-41 confirmed a mesoporous structure of MCM-41. Surface areas of all RH-AlMCM-41 were in the range of 700-800 m 2 /g, lower than that of the parent RH-MCM-41, which was 1230 m 2 /g. After Al addition the Si/Al ratios of RHAlMCM-41(75) and RH-AlMCM-41(25) were higher than that of the parent RH-MCM-41. The RH-AlMCM-41 materials were used as supports for bimetallic platinum−iron catalysts, denoted as Pt-Fe/RH-AlMCM-41, with Pt and Fe amounts of 0.5 and 5.0% by weight, respectively. Results from TPR indicated that the presence of Al might assist the interaction between Pt and Fe as the reduction temperature of iron oxides shifted to a lower value. All catalysts were active for phenol hydroxylation using H 2 O 2 as an oxidant, for which the highest conversions were observed on the RH-MCM-41 material with the highest surface area. The acidity of the supports did not present a significant role in improving the catalytic performance.

show abstract

Platinum catalysed wet oxidation of phenol in a stirred slurry reactor

Cited by 41 publications

References 25 publications

Carbon supported platinum catalysts for catalytic wet air oxidation of refractory carboxylic acids

Carbon supported platinum catalysts for catalytic wet air oxidation of refractory carboxylic acids

Application of the operating window concept to remediation‐option selection

Characterization of AlMCM-41 synthesized with rice husk silica and utilization as supports for platinumiron catalysts

Contact Info

Product

Resources

About