Effect of metal oxides and black carbon (soot) on SO[sub 2]/O[sub 2]/H[sub 2]O reaction systems

Journal Article · Sun Aug 01 00:00:00 EDT 1993 · Aerosol Science and Technology; (United States)

DOI:https://doi.org/10.1080/02786829308959626· OSTI ID:5701701

Chughtai, A R; Brooks, M E; Smith, D M ^[1]

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1. Univ. of Denver, CO (United States)

Particulates of atmospheric interest, including soot, oxidized soot, and oxides of transition metals, [open quotes]fellow travelers[close quotes] in the combustion of solid or liquid fossil fuels, have been examined for their influence on the heterogeneous oxidation of S(IV) to S(VI), both with and without the presence of simulated solar radiation. Under all conditions, MnO[sub 2] has been found to be the most active of the materials in this study. Effectiveness for the oxidation of SO[sub 2] in the presence of oxygen and water vapor decreases in the order: MnO[sub 2] [much gt] V[sub 2]O[sub 5] > CuO > Fe[sub 2]O[sub 3] > Al[sub 2]O[sub 3] > Soot > TiO[sub 2] = SiO[sub 2] (cab-o-sil) [approximately] ZnO > ozonized soot = blank. The oxidation of SO[sub 2] also was carried out in the presence of soot-MnO[sub 2], soot-V[sub 2]O[sub 5], and soot-Fe[sub 2]O[sub 3] mixtures. The respective sulfate yields were found to be significantly higher than those obtained under similar conditions for the individual substrates. Other combinations, such as MnO[sub 2]/V[sub 2]O[sub 5] and MnO[sub 2]/Fe[sub 2]O[sub 3], yielded sulfate at levels higher than those obtained by any of the transition metal oxides or other oxide mixtures used. The mixing ratio of 1:0.75 (wt/wt) in the MnO[sub 2]/V[sub 2]O[sub 5] mixture was found to be optimum. With this mixture the sulfate yield was nearly twice the amount obtained if only MnO[sub 2] was used and nearly four times the amount if V[sub 2]O[sub 5] was used alone. Extensive analyses of the optimum mixture, to detect any unique identity, were inconclusive. 49 refs., 9 figs.

• OSTI ID: 5701701
• Journal Information: Aerosol Science and Technology; (United States), Vol. 19:2; ISSN 0278-6826
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
AEROSOLS
CHEMICAL REACTIONS
FOSSIL FUELS
COMBUSTION
SULFUR DIOXIDE
OXIDATION
CARBON BLACK
OXIDES
OXYGEN
SOOT
TRANSITION ELEMENT COMPOUNDS
WATER
CARBON
CHALCOGENIDES
COLLOIDS
DISPERSIONS
ELEMENTS
ENERGY SOURCES
FUELS
HYDROGEN COMPOUNDS
NONMETALS
OXYGEN COMPOUNDS
SOLS
SULFUR COMPOUNDS
SULFUR OXIDES
THERMOCHEMICAL PROCESSES
540120* - Environment
Atmospheric- Chemicals Monitoring & Transport- (1990-)
400201 - Chemical & Physicochemical Properties