A temperature control and desorption system was developed to assist in the collection of vapor phase samples for GC/MS analysis. The GC/MS utilized for this experiment (Griffin 450) incorporates a direct vapor collection system that bypasses the traditional injection port. Vapor pressure is largely temperature dependent, so an external thermal stabilization system and desorber was constructed using a Raspberry Pi 2 mini-computer and Arduino microcontroller to quickly and accurately control the temperature of samples before transfer to the head of the GC column. Temperature control and stabilization allow for certain chemicals to be vaporized that would not normally be present at meaningful concentrations during ambient room temperature analysis. To achieve this, the system utilizes a braided cartridge heater, a 40 mm DC fan, and an analog temperature sensor that work via negative feedback to reach and maintain the selected heating temperature. The software was programmed in Arduino-variant C++. The system was able to reach temperatures of up to 320 °C with an average error of ± 1.5 °C from the selected input temperature. The accuracy of the desorber’s heating capabilities in vapor analysis was tested against known standards. Future work will focus on the construction of a heat sink and 3D-printed casing to allow for better temperature regulation and portability.

Development of a raspberry Pi and Arduino-based thermal controller and desorber for GC/MS vapor analysis

255th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.