Evaluation of downer reactor performance by catalytic ozone decomposition

A series of soil slurry experiments was performed to investigate the characteristics of PAHs removal by ozone in various conditions. Gaseous ozone was bottled into the aqueous phase in the presence of soil contaminated by PAHs. The effects of soil media, OH radical scavengers, ozone dosage, and humic acid were examined at the given experimental conditions. There exists a substantial difference in the removal of PAH according to the types of soil media tested. Baked sand showed the highest removal efficiency compared to the others. The descending order of removal rate was: BS>S>GB. This is considered to be due to the OH radical effect produced by catalytic reactions of ozone with the reactive site on the and. This is qualitatively proved by the experiment of scavenging OH radicals using tert-butanol. The comparison of half-lives of ozone in sand and glass bead columns further supports this hypothesis. It was found that about 22% of enhancement of phenanthrene destruction was accomplished by OH radicals produced by the catalytic ozone decomposition. The rate of ozone consumption for the phenanthrene oxidation was obtained as 1.88 mg/mgO3/min.

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Ozone decomposition

Interdisciplinary Toxicology ◽

10.2478/intox-2014-0008 ◽

2014 ◽

Vol 7 (2) ◽

pp. 47-59 ◽

Cited By ~ 55

Author(s):

Todor Batakliev ◽

Vladimir Georgiev ◽

Metody Anachkov ◽

Slavcho Rakovsky ◽

Slavcho Rakovsky

Keyword(s):

Noble Metals ◽

Toxic Substance ◽

Chemical Properties ◽

Precious Metals ◽

Catalytic Decomposition ◽

High Price ◽

Catalyst Characterization ◽

Ozone Decomposition ◽

Considerable Work ◽

Catalytic Ozone

ABSTRACT Catalytic ozone decomposition is of great significance because ozone is a toxic substance commonly found or generated in human environments (aircraft cabins, offices with photocopiers, laser printers, sterilizers). Considerable work has been done on ozone decomposition reported in the literature. This review provides a comprehensive summary of the literature, concentrating on analysis of the physico-chemical properties, synthesis and catalytic decomposition of ozone. This is supplemented by a review on kinetics and catalyst characterization which ties together the previously reported results. Noble metals and oxides of transition metals have been found to be the most active substances for ozone decomposition. The high price of precious metals stimulated the use of metal oxide catalysts and particularly the catalysts based on manganese oxide. It has been determined that the kinetics of ozone decomposition is of first order importance. A mechanism of the reaction of catalytic ozone decomposition is discussed, based on detailed spectroscopic investigations of the catalytic surface, showing the existence of peroxide and superoxide surface intermediates

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Manganese-based layered double hydroxide nanoparticles as highly efficient ozone decomposition catalysts with tunable valence state

Nanoscale ◽

10.1039/d0nr02796k ◽

2020 ◽

Vol 12 (24) ◽

pp. 12817-12823

Author(s):

Siyu Wang ◽

Yu-quan Zhu ◽

Yuhong Zhang ◽

Binxia Wang ◽

Hong Yan ◽

...

Keyword(s):

Layered Double Hydroxide ◽

Valence State ◽

Ozone Decomposition ◽

Highly Efficient ◽

Valence States ◽

Double Hydroxide ◽

Catalytic Ozone ◽

Layered Double Hydroxide Nanoparticles

This paper reported a Mn based layered double hydroxide catalyst with tunable valence state, and the effects of different valence states on catalytic ozone decomposition.

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