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

Abstract 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 (278–298 K) using a bubble column system coupled to a Fourier transform infrared spectrometer. The K H values of TEA in water and 1‐octanol at 298 K are 5.75 ± 0.86 mol L −1 atm −1 and 115.62 ± 5.78 mol L −1 atm −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 5.6 µm are ~33 s (298 K, pH = 5.6); ~8.9 × 10 2 s (278 K, pH = 5.6); ~1.3 × 10 3 s (298 K, pH = 4.0); and 3.6 × 10 4 s (278 K, 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.