Chemical coupling between ammonia, acid gases, and fine particles

Environ Pollut. 2004 May;129(1):89-98. doi: 10.1016/j.envpol.2003.09.022.

Abstract

The concentrations of inorganic aerosol components in the fine particulate matter (PM(fine)< or =2.5 microm) consisted of primarily ammonium, sodium, sulfate, nitrate, and chloride are related to the transfer time scale between gas to particle phase, which is a function of the ambient temperature, relative humidity, and their gas phase constituent concentrations in the atmosphere. This study involved understanding the magnitude of major ammonia sources; and an up-wind and down-wind (receptor) ammonia, acid gases, and fine particulate measurements; with a view to accretion gas-to-particle conversion (GTPS) process in an agricultural/rural environment. The observational based analysis of ammonia, acid gases, and fine particles by annular denuder system (ADS) coupled with a Gaussian dispersion model provided the mean pseudo-first-order k(S-1) between NH(3) and H(2)SO(4) aerosol approximately 5.00 (+/-3.77)x10(-3) s(-1). The rate constant was found to increase as ambient temperature, wind speed, and solar radiation increases, and decreases with increasing relative humidity. The observed [NH(3)][HNO(3)] products exceeded values predicted by theoretical equilibrium constants, due to a local excess of ammonia concentration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aerosols / chemistry*
  • Agriculture
  • Air Pollutants / chemistry*
  • Ammonia / chemistry*
  • Background Radiation
  • Environmental Monitoring / methods
  • Gases / chemistry
  • Hydrochloric Acid / chemistry
  • Kinetics
  • Nitrates / chemistry
  • Nitric Acid / chemistry
  • Solar Activity
  • Sulfuric Acids / chemistry
  • Temperature
  • Thermodynamics
  • Wind

Substances

  • Aerosols
  • Air Pollutants
  • Gases
  • Nitrates
  • Sulfuric Acids
  • Nitric Acid
  • Ammonia
  • sulfuric acid
  • Hydrochloric Acid
  • ammonium nitrate