A MEMS µ-Preconcentrator Employing a Carbon Molecular Sieve Membrane for Highly Volatile Organic Compound Sampling

Chemosensors

Chih-Chia Wang¹  Hung-Yen Kuo²  Wei-Riu Cheng²  Chia-Jung Lu²  Tzu-Heng Wu³  Horn-Jiunn Sheen³ 

[1] Department of Chemical and Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Taoyuan 33509,Taiwan;Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan;Institute of Applied Mechanics, National Taiwan University, Taipei 10617, Taiwan;

关键词: preconcentration;    MEMS;    VOCs;    carbon molecular sieve membrane;   

DOI  :  10.3390/chemosensors9050104

来源: DOAJ

【 摘 要 】

This paper presents the synthesis and evaluation of a carbon molecular sieve membrane (CMSM) grown inside a MEMS-fabricated μ-preconcentrator for sampling highly volatile organic compounds. An array of µ-pillars measuring 100 µm in diameter and 250 µm in height were fabricated inside a microfluidic channel to increase the attaching surface for the CMSM. The surface area of the CMSM was measured as high as 899 m²/g. A GC peak amplification factor >2 × 10⁴ was demonstrated with gaseous ethyl acetate. Up to 1.4 L of gaseous ethanol at the 100 ppb level could be concentrated without exceeding the capacity of this microchip device. Sharp desorption chromatographic peaks (<3.5 s) were obtained while using this device directly as a GC injector. Less volatile compounds such as gaseous toluene, m-xylene, and mesitylene appeared to be adsorbed strongly on CMSM, showing a memory effect. Sampling parameters such as sample volatilities, sampling capacities, and compound residual issues were empirically determined and discussed.

【 授权许可】

Unknown