Measurement of residence time distribution in microfluidic systems

Abstract We present a method for measuring the residence time distribution (RTD) in microfluidic systems. A piezoelectrically actuated sample injector releases approximately 100 nl of tracer liquid into a microchannel of rectangular cross section. The spreading of the tracer pulse in pressure-driven microflows is monitored with fluorescence microscopy measurements. Residence time distributions are determined for single-phase liquid and segmented gas–liquid microflows, with the RTD being significantly narrower for the latter case. The selected flow conditions are relevant to synthesis in microreactors with residence times up to several minutes.

[1]  H. Lintel,et al.  A piezoelectric micropump based on micromachining of silicon , 1988 .

[2]  G. Taylor.  Dispersion of soluble matter in solvent flowing slowly through a tube , 1953, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[3]  D. Leighton,et al.  Dispersion reduction in pressure-driven flow through microetched channels. , 2001, Analytical chemistry.

[4]  A. Pandit,et al.  Liquid Phase RTD Studies in Sectionalized Bubble Column , 2000 .

[5]  G. Froment,et al.  Chemical Reactor Analysis and Design , 1979 .

[6]  Albert van den Berg,et al.  A silicon integrated miniature chemical analysis system , 1992 .

[7]  Axel Günther,et al.  A microfabricated gas-liquid segmented flow reactor for high-temperature synthesis: the case of CdSe quantum dots. , 2005, Angewandte Chemie.

[8]  O. Levenspiel.  Chemical Reaction Engineering , 1972 .

[9]  Octave Levenspiel,et al.  Notes on the diffusion-type model for the longitudinal mixing of fluids in flow , 1995 .

[10]  Stephen C Jacobson,et al.  Diffusion coefficient measurements in microfluidic devices. , 2002, Talanta.

[11]  P. V. Danckwerts.  Continuous flow systems. Distribution of residence times , 1995 .

[12]  D. Leighton,et al.  Dispersion in large aspect ratio microchannels for open-channel liquid chromatography. , 2003, Analytical chemistry.

[13]  Jyeshtharaj B. Joshi,et al.  Liquid phase backmixing in sparged contactors , 1978 .

[14]  Saif A. Khan,et al.  Microfluidic synthesis of colloidal silica. , 2004, Langmuir : the ACS journal of surfaces and colloids.

[15]  K. Westerterp,et al.  Chemical reactor design and operation , 1983 .

[16]  Clayton J. Radke,et al.  The motion of long bubbles in polygonal capillaries. Part 1. Thin films , 1995, Journal of Fluid Mechanics.

[17]  G. Taylor.  Deposition of a viscous fluid on the wall of a tube , 1961, Journal of Fluid Mechanics.

[18]  W. Deckwer,et al.  Mixing and mass transfer in tall bubble columns , 1974 .

[19]  D. Weitz,et al.  Geometrically mediated breakup of drops in microfluidic devices. , 2003, Physical review letters.

[20]  Andrew G Ewing,et al.  Sample introduction techniques for microfabricated separation devices , 2004, Electrophoresis.

[21]  Chih-Ming Ho,et al.  Transport of bubbles in square microchannels , 2002 .

[22]  P. V. Danckwerts.  Continuous flow systems , 1953 .

[23]  K. Petersen,et al.  Fabrication of an integrated, planar silicon ink-jet structure , 1979, IEEE Transactions on Electron Devices.

[24]  A. Gavriilidis,et al.  A model for predicting axial mixing during gas–liquid Taylor flow in microchannels at low Bodenstein numbers , 2004 .

[25]  A Manz,et al.  Narrow sample channel injectors for capillary electrophoresis on microchips. , 2001, Analytical chemistry.

[26]  David Quéré,et al.  Quick deposition of a fluid on the wall of a tube , 2000 .

[27]  K. Denbigh,et al.  Chemical Reactor Theory: an Introduction , 1965 .

[28]  S. K. Griffiths,et al.  Low-dispersion turns and junctions for microchannel systems. , 2001, Analytical chemistry.

[29]  A. deMello,et al.  On-chip chromatography: the last twenty years. , 2002 .

[30]  H. S. Fogler,et al.  Elements of Chemical Reaction Engineering , 1986 .

[31]  Clayton J. Radke,et al.  The motion of long bubbles in polygonal capillaries. Part 2. Drag, fluid pressure and fluid flow , 1995, Journal of Fluid Mechanics.

[32]  Roger D. Kamm,et al.  Numerical studies of steady flow dispersion at low Dean number in a gently curving tube , 1986, Journal of Fluid Mechanics.

[33]  Jyeshtharaj B. Joshi,et al.  Axial mixing in multiphase contactors - a unified correlation , 1980 .

[34]  Saif A. Khan,et al.  Transport and reaction in microscale segmented gas-liquid flow. , 2004, Lab on a chip.

[35]  F. Bretherton.  The motion of long bubbles in tubes , 1961, Journal of Fluid Mechanics.

[36]  Axel Günther,et al.  Micromixing of miscible liquids in segmented gas-liquid flow. , 2005, Langmuir : the ACS journal of surfaces and colloids.

[37]  K. Jensen,et al.  An integrated multiphase flow sensor for microchannels , 2004 .

[38]  Reiner Badura,et al.  Durchmischung in Blasensäulen , 1974 .

[39]  E. Bassous,et al.  Ink jet printing nozzle arrays etched in silicon , 1977 .

[40]  Geoffrey Ingram Taylor,et al.  The dispersion of matter in turbulent flow through a pipe , 1954, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.