Kinetics and mechanism of the oxidation of HSO[sub 3][sup [minus]] by HSO[sub 5][sup [minus]]

Journal Article · Wed Mar 03 04:00:00 EST 1993 · Inorganic Chemistry; (United States)

DOI:https://doi.org/10.1021/ic00057a013· OSTI ID:6708184

Connick, R E; Lee, Shaoyung; Adamic, R ^[1]

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1. Univ. of California, Berkeley (United States)

The oxidation of bisulfite ion is of importance in flue gas desulfurization processes and in the conversion of gaseous SO[sub 2] into acid rain in water droplets in the atmosphere. The oxidation of bisulfite ion by peroxymonosulfate ion, HSO[sub 5][sup [minus]], to form sulfate ion has been studied in the pH region 3.8-7.9. The reaction HSO[sub 5][sup [minus]] + HSO[sub 3][sup [minus]] [yields] 2SO[sub 4][sup 2[minus]] + 2H[sup +] was found to obey the rate law -d[HSO[sub 5][sup [minus]]]/dt = [l brace]k[sub a][alpha][sub H[sup +]] + k[sub b][alpha][sub H[sup +]][sup [minus]1] + k[sub c][r brace][l brace]HSO[sub 5][sup [minus]][HSO[sub 3][sup [minus]]], where [alpha][sub H[sup +]] is the activity of hydrogen ion. At 25[degrees]C and ionic strength 0.0050 M the rate constants k[sub a], k[sub b], and k[sub c] have the values 1.27 [times] 10[sup 7], 6.4 [times] 10[sup [minus]5], and 55 M[sup [minus]1] S[sup [minus]1], with the activity of hydrogen ion taken to be dimensionless. For the reaction path corresponding to the k[sub a] term, 90% of the reaction yields the intermediate pyrosulfate ion, S[sub 2]O[sub 7][sup 2[minus]], which then hydrolyzes with about a 1-min lifetime to sulfate and hydrogen ions. Similarly the k[sub c] path forms mostly S[sub 2]O[sub 7][sup 2[minus]] as an intermediate. The k[sub b] path appears to all go directly to sulfate ion. Possible mechanisms for the various reaction paths are discussed. 25 refs., 4 figs., 3 tabs.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6708184
• Journal Information: Inorganic Chemistry; (United States), Journal Name: Inorganic Chemistry; (United States) Vol. 32:5; ISSN 0020-1669; ISSN INOCAJ
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010800 -- Coal
Lignite
& Peat-- Waste Management
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ANIONS
CHALCOGENIDES
CHARGED PARTICLES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
IONS
KINETICS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PH VALUE
REACTION INTERMEDIATES
REACTION KINETICS
REDUCTION
SULFUR COMPOUNDS
SULFUR OXIDES