A miniaturized hydrogen flame ionization detector based on integrated nozzle assembly and embedded sealing structure

Abstract

A modified miniaturized hydrogen flame ionization detector (m-FID) was developed and evaluated. An integrated nozzle assembly was constructed to solve the gas leakage caused by adhesive crack during repeated high-low temperature processes or vibration. An embedded sealing structure was designed to realize the face sealing, thus improving the sealing stability and reliability of the m-FID. Polyimide was employed as seal and insulation material to ensure the detector can be used at 300 °C for a long term. The hydrogen and air consumption of the m-FID was 12 mL/min and 110 mL/min, which is about 1/3 of the FID gas consumption of commercial laboratory instruments. The limit of detection (LOD) for n-hexadecane was 3.2 × 10−12 g/s, with a linear response range of nearly 5 orders of magnitude. Finally, it was installed onto an on-site gas chromatograph to detect drug samples with wide boiling point range from room temperature up to 535 °C.