Thermal-managed sputtered micro machined gas chromatography columns for oilfield applications

R. Haudebourg, J. Vial, D. Thiébaut, P. Sassiat, I. Azzouz, K. Danaie, B. Bourlon
Schlumberger, FR

Keywords: gas chromatography, micro electro mechanical system (MEMS), sputtering, silica, graphite, thermal management


Since the late 70s, new approaches have been proposed to replace conventional gas chromatograph apparatus by silicon based micro fabricated separation systems. The main challenge in miniaturized gas chromatography consists in the reproducible and collective fabrication of micro columns. Indeed, the critical step of coating is hardly compatible with miniaturization and mass production. In a previous publication, we presented how the rerouting of the sputtering technique to coat columns with a thin film of silica was able to answer this issue (patent pending). We presented promising isothermal separations of light alkanes on silica sputtered micro columns. In order to go beyond the limitations of isothermal separations, and to enable faster and cycled analysis, the micro columns were then equipped with a computer controlled thermal management micro system, including cooling, heating, and temperature reading. Heating rates up to 10°C/s were achieved. The separation performances of silica sputtered micro columns coupled with thermal management were investigated: a full separation of light alkanes (C1 – C7) was completed in 22 s. The potentialities of sputtered graphite as an alternative stationary phase for specific applications unreachable with silica were also established (permanent gases separation, high ambient temperature separation).