Automated Monitoring of VOCs with a Compact Gas Chromatography-Proton Transfer Reaction Mass Spectrometer (GC -Vocus)

Volatile organic compounds (VOCs) are emitted from a wide variety of biogenic and anthropogenic sources. VOCs transform in the atmosphere, forming ozone and oxygenated VOCs (OVOCs), which in turn can form fine particulates or condense onto preexisting particulate matter (PM). Both ozone and fine PM are deleterious to human health and alter the Earth’s climate. Measurements of VOCs and OVOCs are necessary to model the sources and sinks of harmful atmospheric chemicals. Progress in this area is limited, however, by the lack of field-deployable instrumentation capable of providing detailed molecular information. The goal of the proposed work is to develop a hybrid gas chromatograph and a lower resolution proton transfer reaction Vocus mass spectrometer (GC-Vocus) instrument capable of real-time molecular-level chemical characterization of VOCs and OVOCs. Phase I resulted in a prototype instrument and software capable of measuring VOCs and OVOCs. The result of Phase II will be a GCVocus instrument that is capable of fully autonomous, real-time, robust, and sensitive measurements of VOCs and OVOCs.