020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY Jiri SEVCIK Prague, the Czech Republic

020219GKRECYCLE GC ABOUT CHARACTERISTICS SEPARATION EFFICIENCY RESOLUTION RECYCLE CHROMATOGRAPHY HW

020219GKRECYCLE GC multidimensional chromatography SYSTEMS serial parallel K D1 <> K D2 <> K Dd

020219GKRECYCLE GC SCHEMATICS of recycle chromatography INJECT R 1 t M w 0 INTER FACE t Mex w ew COLUMN t Ra /, t Rb / w a, w b R 2 DETECT t Mdet w det LOOP COUNTER i

020219GKRECYCLE GC recycle chromatography COMPONENTS AND VARIATIONS componentspossibilities chromatographyGCLC column typepackedcapillary switching interface valvevalveless end column split mobile phase source const. P const. Fpump

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY PARAMETERS retention time elution profile width separation efficiency resolution

020219GKRECYCLE GC RETENTION TIME in recycle chromatography INJECT R 1 t M INTER FACE t Mex COLUMN t Ra /, t Rb / R 2 DETECT t Mdet LOOP COUNTER i

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY RETENTION TIME from an injector to a detector within a loop after i loops

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY RETENTION TIME retention time between consecutive cycles is constant total retention time is additive

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY RETENTION TIME PROOF of ADDITIVITY

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY RETENTION TIME PROOF of ADDITIVITY

020219GKRECYCLE GC RETENTION TIME IN RECYCLE CHROMATOGRAPHY

020219GKRECYCLE GC ELUTION PROFILE WIDTH of recycle chromatography INJECT R 1 w 0 INTER FACE w ew COLUMN w a, w b R 2 DETECT w det LOOP COUNTER i

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY ELUTION PROFILE WIDTH from an injector to a detector within a loop after i loops

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY ELUTION PROFILE WIDTH elution profile width between consecutive cycles is constant total peak width is additive in form of their variances

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY PEAK WIDTH PROOF of ADDITIVITY

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY PEAK WIDTH PROOF of ADDITIVITY

020219GKRECYCLE GC PEAK WIDTH IN RECYCLE CHROMATOGRAPHY

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY SEPARATION EFFICIENCY number of effective plates after a loop

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY SEPARATION EFFICIENCY number of effective plates after i loops

020219GKRECYCLE GC RECYCLE SEPARATION EFFICIENCY PROOF of ADDITIVITY

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY EXTRA COLUMN EFFECTS number of effective plates after i loops

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY EXTRA COLUMN EFFECTS ratio n i / n 1

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY EXTRA COLUMN EFFECTS ratio n i / n 1 an inlet part of a column is unefficient THUS efficienty increases faster in recycle system than in nonrecycle system it is not correct to express separation efficiency in terms of the theoretical plate number

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY EXTRA COLUMN EFFECTS

020219GKRECYCLE GC SEPARATION IN RECYCLE CHROMATOGRAPHY retention interval of unseparated mixture in one-dimensional system in recycle system tt t b t a

020219GKRECYCLE GC SEPARATION IN RECYCLE CHROMATOGRAPHY retention interval of unseparated mixture increases over the column lenght untill 1st peak leaves the column while the last one just enters the column then peak will merge again THUS maximum number of cycles tt t b t a

020219GKRECYCLE GC RECYCLE SEPARATION EFFICIENCY PROOF of ADDITIVITY

020219GKRECYCLE GC MAXIMUM NUMBER OF CYCLES IN RECYCLE CHROMATOGRAPHY tt t b t a

020219GKRECYCLE GC RESOLUTION IN RECYCLE CHROMATOGRAPHY retention order can not change because of the same st.phase ( remains constant)

020219GKRECYCLE GC MAXIMUM AVAILABLE RESOLUTION IN RECYCLE CHROMATOGRAPHY

020219GKRECYCLE GC REQUIRED SEPARATION EFFICIENCY IN RECYCLE CHROMATOGRAPHY for required resolution , k and n can be optimized if R ab = 1 an optimum number of cycles results

020219GKRECYCLE GC RECYCLE SEPARATION EFFICIENCY NUMBER of CYCLES

020219GKRECYCLE GC THE OPTIMAL NUMBER OF CYCLES IN RECYCLE CHROMATOGRAPHY for isomers , k=5 and n=20,000 R ab1 = 0,29 and the optimal number of cycles i opt = 3.3

020219GKRECYCLE GC RECYCLE CHROMATOGRAPHY MAXIMAL NUMBER of CYCLES merged at start merged once again maximal separation

020219GKRECYCLE GC MS-SIM separation of GC non separated isomers

020219GKRECYCLE GC recycle capillary GC PRINCIPLE recycling analysed mixture through single capillary column by means of peristaltic pump as mobile phase source and controling actually achieved separation by means of end column splitter

020219GKRECYCLE GC recycle capillary GC CONSTRUCTION peristaltic pump providing optimal column flow for columns from 5 to 50 meters fixed end column splitter

020219GKRECYCLE GC INSTRUMENTATION - interface IN RECYCLE CHROMATOGRAPHY R 1 40 m (injector) R 2 40 m (detector MS) column flow peristaltic pump

020219GKRECYCLE GC recycle capillary GC APPLICATION suited for componds up to C 10 for limited number of compounds with similar physicochemical and chiral properties first time separation of 3 stereoisomers of 3,4-dimethylhexane on β–cyclodextrine with 2,000,000 plates

020219GKRECYCLE GC nonselective separation Carbowax 20M 300 m, 250 µm n = 500,000 n-dodecene isomers

020219GKRECYCLE GC selectivity of separation separation of isomers also with a functional group in middle of carbon chain n-dodecenes

020219GKRECYCLE GC MS-SIM separation of GC non separated isomers

020219GKRECYCLE GC ABOUT CHARACTERISTICS SEPARATION EFFICIENCY RESOLUTION RECYCLE CHROMATOGRAPHY HW

020219GKRECYCLE GC NEW GC METHODS development sample preparation efficiency selectivity hyphenation sensitivity detection software ITP - GC recycle GC stationary phases comprehensive thermal modulation spectral detectors deconvolution toward reduced ultimate uncertainty