Heterogeneous Formation of HONO on HNO3 Pre-Conditioned Hydrophobic, Hydrophilic and Ionic Surfaces at Various Relative Humidities

Author

Dustin S. Wier, Western Michigan University

Date of Award

4-2007

Degree Name

Master of Science

Department

Chemistry

First Advisor

Dr. John Miller

Second Advisor

Dr. Steve Bertman

Third Advisor

Dr. James Kiddle

Access Setting

Masters Thesis-Open Access

Abstract

Nitric acid (HNO₃) is a major sink for NO_x (NO+NO₂ ) and is known to be removed from the atmosphere as a result of wet and dry deposition where it is then deposited on various surfaces in the environment. As these surfaces are photolyzed HONO is produced which affects the overlying troposphere. This study examines the amount of HONO (Nitrous Acid) produced by the photolysis of adsorbed HNO₃ as a function of changing relative humidity on hydrophobic, hydrophilic, and inorganic ionic salt surfaces. The amount of HONO produced was measured in long path cell using UV/Vis spectroscopy. This study also narrows down the excitation wavelength range responsible for photolysis. This was accomplished by placing a series of optical filters in-between the surface and the source of radiation. Further examination of the data reveals interesting mechanistic information for HONO production.

Recommended Citation

Wier, Dustin S., "Heterogeneous Formation of HONO on HNO3 Pre-Conditioned Hydrophobic, Hydrophilic and Ionic Surfaces at Various Relative Humidities" (2007). Masters Theses. 4254.
https://scholarworks.wmich.edu/masters_theses/4254