Reaction kinetics of nitrogen dioxide with liquid water at low partial pressure

Journal Article · Thu Apr 02 00:00:00 EST 1981 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j150607a022· OSTI ID:6508133

Lee, Y N; Schwartz, S E

The reaction 2NO/sub 2/(g) + H/sub 2/O(l) ..-->.. 2H/sup +/ + NO/sub 3//sup -/ + NO/sub 2//sup -/ (l) has been studied for 1 x 10/sup -7/ less than or equal to P/sub NO2/ less than or equal to 8 x 10/sup -4/ atm. Since this reaction involves the transfer of a reactant from the gas into the aqueous phase, the rate depends upon the following: (a) physical mass transfer of the reactant, (b) the equilibrium solubility of NO/sub 2/, and (c) homogeneous aqueous-phase kinetics. In order for the observed rate to yield information most sensitive to (c), the rate of (a) must be comparable to that of (c). In the case of a second-order reaction, this can be achieved by working at low partial pressure of NO/sub 2/ as well as a high rate of physical mixing of the two phases. To facilitate the latter, the gas was brought into contact with the liquid as finely dispersed bubbles produced by flowing through a disk-frit; the mass transfer time constant, determined by uptake of CO/sub 2/, was tau/sub m/ = 1.7 to 5.3 s. The rate of reaction 1, monitored by observing the electrical conductivity of the aqueous solution, exhibited dependence on p/sub NO2/ and tau/sub m/ consistent with second-order kinetics and a steady-state aqueous-phase NO/sub 2/ concentration. Values of H/sub NO2/, the Henry's law coefficient, and k/sub 1/, the second-order aqueous-phase rate constant, were determined to be (7.0 +- 0.5) x 10/sup -3/M atm/sup -1/ and (1.0 +- 0.1) x 10/sup 8/M/sup -1/s/sup -1/, respectively, at 22/sup 0/C. Self-consistency of the gas-liquid reaction model has been demonstrated in terms of the identity of the diffusing species and the extent of mass-transport limitation.

• Research Organization: Brookhaven National Lab., Upton, NY
• OSTI ID: 6508133
• Journal Information: J. Phys. Chem.; (United States), Vol. 85:7
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
54 ENVIRONMENTAL SCIENCES
NITRIC ACID
CHEMICAL REACTION YIELD
NITROGEN DIOXIDE
CHEMICAL REACTIONS
WATER
ATMOSPHERIC CHEMISTRY
BUBBLES
CHEMICAL REACTION KINETICS
DISSOLUTION
LIQUIDS
MASS TRANSFER
PRESSURE DEPENDENCE
SOLUBILITY
CHALCOGENIDES
CHEMISTRY
FLUIDS
HYDROGEN COMPOUNDS
INORGANIC ACIDS
KINETICS
NITROGEN COMPOUNDS
NITROGEN OXIDES
OXIDES
OXYGEN COMPOUNDS
REACTION KINETICS
YIELDS
400201* - Chemical & Physicochemical Properties
500200 - Environment
Atmospheric- Chemicals Monitoring & Transport- (-1989)