An improved approach for measuring Henry's law coefficients of atmospheric organics

In this work, we present an improved method for Henry's law constant, K_H, measurements by coupling a bubble column system with a gas cell/infrared spectrometer. To demonstrate the feasibility of this approach, we measured K_H of atmospheric organics from three different classes, namely, toluene (hydrocarbon), sec-butylamine (amine), and cineole (ether). We also reported temperature and ionic strength effects on the K_H values of sec-butylamine for the first time. As shown in this work, the method is highly capable of determining K_H of atmospheric organic species regardless the presence of heteroatoms and the occurrence of hydration in water. It is very versatile, easy to use, reliable, and efficient. It is also well-suited for undergraduate students to conduct environmental chemical science research during academic semesters.