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RECYCLE CHROMATOGRAPHY. Jiri SEVCIK Prague, the Czech Republic. ABOUT. CHARACTERISTICS SEPARATION EFFICIENCY RESOLUTION RECYCLE CHROMATOGRAPHY HW. multi d imensional chromatography SYSTEMS. serial parallel. K D1 <> K D2 <> K Dd. SCHEMATICS of recycle chromatography.
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RECYCLECHROMATOGRAPHY Jiri SEVCIK Prague, the Czech Republic RECYCLE GC
ABOUT • CHARACTERISTICS • SEPARATION EFFICIENCY • RESOLUTION • RECYCLE CHROMATOGRAPHY HW RECYCLE GC
multidimensional chromatographySYSTEMS serial parallel KD1 <> KD2 <> KDd RECYCLE GC
SCHEMATICSof recycle chromatography INJECT R1 tM w0 INTERFACE tMex wew COLUMN tRa/ , tRb/ wa , wb R2 DETECT tMdet wdet LOOP COUNTER i RECYCLE GC
RECYCLE CHROMATOGRAPHYPARAMETERS • retention time • elution profile width • separation efficiency • resolution RECYCLE GC
RETENTION TIMEin recycle chromatography INJECT R1 tM INTERFACE tMex COLUMN tRa/ , tRb/ R2 DETECT tMdet LOOP COUNTER i RECYCLE GC
RECYCLE CHROMATOGRAPHYRETENTION TIME • from an injector to a detector • within a loop • after i loops RECYCLE GC
RECYCLE CHROMATOGRAPHYRETENTION TIME • retention time between consecutive cycles is constant • total retention time is additive RECYCLE GC
RECYCLE CHROMATOGRAPHYRETENTION TIME PROOF of ADDITIVITY RECYCLE GC
RECYCLE CHROMATOGRAPHYRETENTION TIME PROOF of ADDITIVITY RECYCLE GC
RETENTION TIMEIN RECYCLE CHROMATOGRAPHY RECYCLE GC
ELUTION PROFILE WIDTHof recycle chromatography INJECT R1 w0 INTERFACE wew COLUMN wa , wb R2 DETECT wdet LOOP COUNTER i RECYCLE GC
RECYCLE CHROMATOGRAPHYELUTION PROFILE WIDTH • from an injector to a detector • within a loop • after i loops RECYCLE GC
RECYCLE CHROMATOGRAPHYELUTION PROFILE WIDTH • elution profile width between consecutive cycles is constant • total peak width is additive in form of their variances RECYCLE GC
RECYCLE CHROMATOGRAPHYPEAK WIDTH PROOF of ADDITIVITY RECYCLE GC
RECYCLE CHROMATOGRAPHYPEAK WIDTH PROOF of ADDITIVITY RECYCLE GC
PEAK WIDTHIN RECYCLE CHROMATOGRAPHY RECYCLE GC
RECYCLE CHROMATOGRAPHYSEPARATION EFFICIENCY • number of effective plates • after a loop RECYCLE GC
RECYCLE CHROMATOGRAPHYSEPARATION EFFICIENCY • number of effective plates after i loops RECYCLE GC
RECYCLE CHROMATOGRAPHYEXTRA COLUMN EFFECTS • number of effective plates after i loops RECYCLE GC
RECYCLE CHROMATOGRAPHYEXTRA COLUMN EFFECTS • ratio ni / n1 RECYCLE GC
RECYCLE CHROMATOGRAPHYEXTRA COLUMN EFFECTS • ratio ni / n1 • aninlet 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 RECYCLE GC
RECYCLE CHROMATOGRAPHYEXTRA COLUMN EFFECTS RECYCLE GC
SEPARATION IN RECYCLE CHROMATOGRAPHY • retention interval of unseparated mixture • in one-dimensional system • in recycle system tD tb ta RECYCLE 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 tD tb ta RECYCLE GC
MAXIMUM NUMBER OF CYCLESIN RECYCLE CHROMATOGRAPHY tD tb ta RECYCLE GC
RESOLUTIONIN RECYCLE CHROMATOGRAPHY • retention order can not change because of the same st.phase (a remains constant) RECYCLE GC
MAXIMUM AVAILABLE RESOLUTIONIN RECYCLE CHROMATOGRAPHY RECYCLE GC
REQUIRED SEPARATION EFFICIENCYIN RECYCLE CHROMATOGRAPHY • for required resolution • a , k and n can be optimized • if Rab = 1 an optimum number of cycles results RECYCLE GC
THE OPTIMAL NUMBER OF CYCLESIN RECYCLE CHROMATOGRAPHY • for isomers a=1.01 , k=5and n=20,000 Rab1 = 0,29 and the optimal number of cycles iopt= 3.3 RECYCLE GC
RECYCLE CHROMATOGRAPHYMAXIMAL NUMBER of CYCLES merged at start maximal separation merged once again RECYCLE GC
recycle capillary GCPRINCIPLE • 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 RECYCLE GC
recycle capillary GCCONSTRUCTION • peristaltic pump providing optimal column flow for columns from 5 to 50 meters • fixed end column splitter RECYCLE GC
INSTRUMENTATION - interface IN RECYCLE CHROMATOGRAPHY peristaltic pump R1 40 mm (injector) R2 40 mm (detector MS) flow column RECYCLE GC
recycle capillary GCAPPLICATION • suited for componds up to C10 • 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 RECYCLE GC
nonselective separation • Carbowax 20M • 300 m, 250 µm • n = 500,000 • n-dodecene isomers RECYCLE GC
selectivity of separation • separation of isomers also with a functional group in middle of carbon chain • n-dodecenes RECYCLE GC
ABOUT • CHARACTERISTICS • SEPARATION EFFICIENCY • RESOLUTION • RECYCLE CHROMATOGRAPHY HW RECYCLE GC
sample preparation efficiency selectivity hyphenation sensitivity detection software ITP - GC recycle GC stationary phases comprehensive thermal modulation spectral detectors deconvolution NEW GC METHODS development toward reduced ultimate uncertainty RECYCLE GC