synthesis and catalytic activity of dispersed manganese(iv) oxides in the reaction of ozone decomposition
Clicks: 233
ID: 132920
2017
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This
article has not been analysed, so there is no overall score —
reader engagement is measured and shown alongside.
Reader Engagement
Popular Article
30.0
/100
233 views
45 readers
AI Quality Assessment
Not analyzed
Readership in this journal
PopularRanked #251 of 485 articles by views in Nature communications
Most read
Least read
Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 485 in total.
Mint this article as an NFT
Not yet mintedCreate a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.
5
SUSD
one-off · no wallet required
Abstract
MnO2 samples were prepared via different procedures: (i) permanganate ion reducing with formic acid followed by the precipitate washing with cold (IS-Mn(1)) or hot (IS-Mn(2)) water, (ii) permanganate ion reducing with Mn2+ ion (IIS-Mn), and (iii) KNO3 and MnSO4 melting together (IІІS-Mn). It has been found by X-ray diffraction (XRD) method that, among Mn(IV) samples synthesized via above procedures, IS-Mn(1), IS-Mn(2), and ІІSMn are semiamorphous and only IIS-Mn contains ε-MnO2 and g-MnO2 phases. IІІS-Mn is crystalline and positions and intensities of its reflections in XRD patterns can be attributed to the cryptomelane, KMn8O16, phase having a tunnel (2´2) structure with potassium ions in its channels. Using a Rietveld refinement, it has been determined that a size of cryptomelane crystallites is several times as much as sizes of the semiamorphous ε-MnO2 and g-MnO2 crystallites. As a result of testing the IS-Mn(1), IIS-Mn, and IІІS-Mn samples in the reaction of ozone decomposition at C in O3 = 100 mg/m3, it has been found that the reaction kinetics depends on the nature of the samples and their weights. Varying catalyst weight we draw a conclusion that an effective residence time, t¢, and a specific volume flow (wsp) of ozone-air mixture (OAM) also change. At the invariant linear velocity of OAM, the residence time increases because a height of the catalyst bed increases. Moreover, increasing the catalyst weight, we obtain a decrease in wsp. The increase in τ¢ leads to the increase in kinetic and stoichiometric parameters of the reaction for all samples under study. In the case of IIS-Mn and IІІS-Mn at the sample weight of 0.5 g, we failed to achieve the half-conversion of ozone, i.e. ozone concentration at the reactor outlet, C fO3 , didn’t become equal to 0.5 C in O3 , therefore, we stopped the experiments when C in O3 attained 5 mg/m3 for IIS-Mn and 0.28 mg/ m3 for IIISMn. Moreover, these samples have protective abilities: a time of protective action was 180 min for IIS-Mn and 1020 min for IIIS-Mn. Thus, the catalytic activity of manganese oxide forms in the reaction of ozone decomposition depends on their phase composition and crystallinity. Cryptomelane having a tunnel structure (2 × 2) shows the highest activity.
| Reference Key |
rakitskaya2017vsniksynthesis
Use this key to autocite in the manuscript while using
SciMatic Manuscript Manager or Thesis Manager
|
|---|---|
| Authors | ;T. L. Rakitskaya;A. S. Truba;A. V. Nagaevs’ka |
| Journal | Nature communications |
| Year | 2017 |
| DOI |
10.18524/2304-0947.2017.4(64).115916
|
| URL | |
| Keywords |
Citations
No citations found. To add a citation, contact the admin at info@scimatic.org
Comments
No comments yet. Be the first to comment on this article.