A micro gas chromatographic column with embedded elliptic cylindrical posts

In this paper, a novel embeded elliptic cylindrical posts (ECPs) with large surface area and wide effective width, which could support more stationary phase and decrease the pressure drop, is applied on the micro-fabricated gas chromatographic (μGC) column. Compared with μGC column with cylindrical posts (CPs), the surface area and effective width of μGC column with ECPs are increased by 29% and 30%. Separation experiments are performed under the same head pressure at column inlet: in experiments of separating mixture 1, the column efficiency of the μGC column with ECPs for C9 has a 76% improvement, and the separation resolution between C8 and C9 also has a 34% improvement; in experiments of separating mixture 2, seven kinds of analytes can be identified by the μGC column with ECPs less than ten minutes, while, only six kinds can be identified by the μGC column with CPs in almost the same time. In detail, the column efficiency of the μGC column with ECPs for toluene has a 129% improvement, and the separation resolution between benzene and toluene also has a 56.4% improvement. Hence, the μGC column with the inner structures of ECPs is a valid means to improve column efficiency and resolution in a lower pressure drop.