Effects of temperature, pH, and ionic strength on the Henry's law constant of triethylamine

The Henry's law constants (K_H) of triethylamine (TEA) in pure water and in 1-octanol were measured for the temperatures pertinent to the lower troposphere (278-298K) using a bubble column system coupled to a Fourier transform infrared spectrometer. The K_H values of TEA in water and 1-octanol at 298K are 5.75±0.86molL^-1atm^-1 and 115.62±5.78molL^-1atm^-1. The K_H values display strong dependence on temperature, pH, and ionic strength. The characteristic times for TEA to establish an equilibrium between gas and droplet with a size of 5.6μm are ∼33s (298K, pH=5.6); ∼8.9×10²s (278K, pH=5.6); ∼1.3×10³s (298K, pH=4.0); and 3.6×10⁴s (278K, pH=4.0). The evaluation of TEA partitioning between gas phase and condensed phase implies that TEA predominantly resides in rainwater, and TEA loss to organic aerosol is negligible.