020219GK RECYCLE GC

RECYCLE

CHROMATOGRAPHY

Jiri SEVCIKPrague, the Czech Republic

020219GK RECYCLE GC

ABOUT

CHARACTERISTICS

SEPARATION EFFICIENCY

RESOLUTION

RECYCLE CHROMATOGRAPHY HW

020219GK RECYCLE GC

multidimensional chromatographySYSTEMS

                

 

                       

 

serial

parallel

KD1 <> KD2 <> KDd

020219GK RECYCLE GC

SCHEMATICSof recycle chromatography

INJECT R1

tM

w0

  

INTERFACE

tMex

wew

COLUMN 

tRa/ , tRb

/

wa , wb

R2 DETECT

tMdet

wdet

 

LOOP COUNTER i

020219GK RECYCLE GC

recycle chromatographyCOMPONENTS AND VARIATIONS

components possibilities

chromatography

GC LC

column type packed capillary

switching interface

valve valvelessend column split

mobile phase source

const. P const. F pump

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYPARAMETERS

retention time elution profile width separation efficiency resolution

020219GK RECYCLE GC

RETENTION TIMEin recycle chromatography

INJECT R1

tM

  

INTERFACE

tMex

COLUMN 

tRa/ , tRb

/

R2 DETECT

tMdet

LOOP COUNTER i

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYRETENTION TIME

from an injector to a detector

within a loop after i loops

det/

1 MRaMexMRa ttttt

/12 RaMexRaRa tttt

/1 1 RaMexRaiRa ttitt

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYRETENTION TIME

retention time between consecutive cycles is constant total retention time is additive

consttttt RaMexiRaiRa /

1

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYRETENTION TIME PROOF of ADDITIVITY

Retention time increment - 20 metresy = 1E-05x + 1,4435

R2 = 0,0136

1,430

1,435

1,440

1,445

1,450

1,455

1,460

0 50 100 150 200 250total time [min]

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYRETENTION TIME PROOF of ADDITIVITY

Retention time increment - 50 metresy = -3E-05x + 4,6388

R2 = 0,0109

4,5904,6004,6104,6204,6304,6404,6504,6604,6704,6804,690

0 50 100 150 200total time [min]

020219GK RECYCLE GC

RETENTION TIME IN RECYCLE CHROMATOGRAPHY

E:\cyklicka\met4 21.07.1999 07:54:15

RT: 0,00 - 200,00 SM: 15B

0 5 10 15 20 25 30 35 40 45 50 55 60 65

Time (min)

0

20

40

60

80

100 NL:1,34E8

TIC MS met4

70 75 80 85 90 95 100 105 110 115 120 125 130

Time (min)

0

1

2

3

Rel

ativ

e Ab

unda

nce

NL:1,34E8

TIC MS met4

135 140 145 150 155 160 165 170 175 180 185 190 195

Time (min)

0,0

0,2

0,4

0,6

0,8

NL:1,34E8

TIC MS met4

020219GK RECYCLE GC

ELUTION PROFILE WIDTHof recycle chromatography

INJECT R1

w0

  

INTERFACE

wew

COLUMN 

wa , wb

R2 DETECT

wdet

 

LOOP COUNTER i

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYELUTION PROFILE WIDTH

from an injector to a detector

within a loop after i loops

2

det222

02

1 wwwww aexa

2221

22 aexaa wwww

2221

2 1 aexaia wwiww

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYELUTION PROFILE WIDTH

elution profile width between consecutive cycles is constant total peak width is additive in form of their variances

constwwww aexiaia 222

12

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYPEAK WIDTH PROOF of ADDITIVITY

Width increment - 20 metres y = 0,0036x + 1,7421

R2 = 0,0016

-40

-30

-20

-10

0

10

20

30

0 50 100 150 200 250 300 350

profile width [sec2]

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYPEAK WIDTH PROOF of ADDITIVITY

Width increment - 50 metres y = 0,0113x + 5,9856

R2 = 0,0075

-20

-10

0

10

20

30

40

0 50 100 150 200 250 300 350

profile width [sec2]

020219GK RECYCLE GC

PEAK WIDTH IN RECYCLE CHROMATOGRAPHY

y = 0,0007x - 0,0014

R2 = 0,9985

0

0,02

0,04

0,06

0,08

0,1

0 20 40 60 80 100 120 140

i

wa(

i)2 [

min

2 ]

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYSEPARATION EFFICIENCY

number of effective plates

after a loop

2

2)1(

)1()(

*16 det)1(

a

MMMR

w

ttttn exa

2

2)2(

)2()*2(

*16 det)2(

a

MMMR

w

ttttn exa

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYSEPARATION EFFICIENCY

number of effective plates after i loops

2)1(

2)1()(*)1(

1

**

a

ai

w

wi

inin

020219GK RECYCLE GC

RECYCLE SEPARATION EFFICIENCY PROOF of ADDITIVITY

y = 17148xR2 = 0,9958

y = 1579xR2 = 0,9752

y = 51694xR2 = 0,9866

0

500 000

1 000 000

1 500 000

2 000 000

2 500 000

0 50 100 150

number of loops

plat

e nu

mbe

r

5 metrů

20 metrů

50 metrů

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYEXTRA COLUMN EFFECTS

number of effective plates after i loops

2)1(

2)1()(*)1(

1

**

a

ai

w

wi

inin

2221

22 aexaa wwww

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYEXTRA COLUMN EFFECTS

ratio ni / n1

Influence of extra-column effects on recycle system efficiency

60

70

8090

100

110

0 2 4 6 8 10 12

number of cycles i

rati

o

(ni/

n1)

in

%

5% 10% 15% 20%

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYEXTRA COLUMN EFFECTS

ratio ni / n1

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

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHYEXTRA COLUMN EFFECTS

cycles t Rw1/2 cycles t R

w1/2

[number] [min] [sec2] [number] [min] [sec2]

1st half 1 to 39 1 to 69mean x = 0,322 1,356 1,444 2,422deviation s = 0,004 1,264 0,002 1,750

2nd half 40 to 78 70 to 138mean x = 0,322 1,071 1,445 2,261deviation s = 0,004 5,216 0,008 12,148

1st and 2nd half 1 to 78 1 to 138mean x = 0,322 1,212 1,445 2,341deviation s = 0,004 3,795 0,006 8,677

linear velocityu [cm*s-1] 25,9 23,1plate numbern (rem.1) 118 002 25,086 104,040 2 270 494 199,540 345,960

column length 5 m column length 20 m

020219GK RECYCLE GC

SEPARATION IN RECYCLE CHROMATOGRAPHY

retention interval of unseparated mixture in one-dimensional system in recycle system

t

tb ta

)(11 ababttt RR

)()( abiaibtitt RR

020219GK 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

t

tb ta

020219GK RECYCLE GC

RECYCLE SEPARATION EFFICIENCY PROOF of ADDITIVITY

0 5 10 15 20 25 30 35 40 45 50 55 60 65

0

20

40

60

80

100

B10 B11

A0+B0

B9 B8 B7 B6 B5

B4 B3

B2 B1

A11 A10 A9 A8 A7 A6 A5 A4 A3

A2 A1

70 75 80 85 90 95 100 105 110 115 120 125 130

0

2

4

6

8

10

12

A12 B22 B21 B20 B19

B18 B17 B16 B15

B14 B13

B12

A23 A22 A21 A20 A19 A18 A17 A16 A15 A14 A13

135 140 145 150 155 160 165 170 175 180 185 190 195 Time (min)

0

1

2

3

4

5

B34

B23

A27+B26

B33 B32 B31 B30 B29 B28 B27 B25 B24

A35 A34 A33 A32 A31 A30 A29 A28

A26 A25 A24

020219GK RECYCLE GC

MAXIMUM NUMBER OF CYCLES IN RECYCLE CHROMATOGRAPHY

t

tb ta

)(

/

maxab

R

t

tINTi a

)(11 ababttt RR

det/

1 MRaMexMRa ttttt

020219GK RECYCLE GC

RESOLUTION IN RECYCLE CHROMATOGRAPHY

retention order can not change because of the same st.phase ( remains constant)

n

kk

kkR

ba

baab *

2*

1

1*

2

1)1

nik

kR

b

bab **

1*

1*

4

1maxmax

020219GK RECYCLE GC

MAXIMUM AVAILABLE RESOLUTION IN RECYCLE CHROMATOGRAPHY

nitt

tR

abR

abab

a

***4

1max

)(/

)(max

max/)( 1

max

1

it

t

R

R

aR

ab

ab

ab

020219GK RECYCLE GC

REQUIRED SEPARATION EFFICIENCY IN RECYCLE CHROMATOGRAPHY

for required resolution , k and n can be optimized if Rab = 1 an optimum number of cycles results

1

1

abopt Ri

n

kk

kkR

ba

baab *

2*

1

1*

2

1)1

reqR

ab

ab

ab

it

t

R

R

areq

1/

)(1

020219GK RECYCLE GC

RECYCLE SEPARATION EFFICIENCY NUMBER of CYCLES

0 5 10 15 20 25 30 35 40 45 50 55 60 65

0

20

40

60

80

100

B10 B11

A0+B0

B9 B8 B7 B6 B5

B4 B3

B2 B1

A11 A10 A9 A8 A7 A6 A5 A4 A3

A2 A1

70 75 80 85 90 95 100 105 110 115 120 125 130

0

2

4

6

8

10

12

A12 B22 B21 B20 B19

B18 B17 B16 B15

B14 B13

B12

A23 A22 A21 A20 A19 A18 A17 A16 A15 A14 A13

135 140 145 150 155 160 165 170 175 180 185 190 195 Time (min)

0

1

2

3

4

5

B34

B23

A27+B26

B33 B32 B31 B30 B29 B28 B27 B25 B24

A35 A34 A33 A32 A31 A30 A29 A28

A26 A25 A24

020219GK RECYCLE GC

THE OPTIMAL NUMBER OF CYCLES IN RECYCLE CHROMATOGRAPHY

for isomers , k=5 and n=20,000

Rab1 = 0,29 and

the optimal number of cycles iopt= 3.3

0

5

10

15

20

25

30

1 1,005 1,01 1,015 1,02 1,025 1,03

selectivity

i

k= 5

k=10

k= 5

k=10

n = 10 000

n = 50 000

020219GK RECYCLE GC

RECYCLE CHROMATOGRAPHY MAXIMAL NUMBER of CYCLES

0 5 10 15 20 25 30 35 40 45 50 55 60 65

0

20

40

60

80

100

B10 B11

A0+B0

B9 B8 B7 B6 B5

B4 B3

B2 B1

A11 A10 A9 A8 A7 A6 A5 A4 A3

A2 A1

70 75 80 85 90 95 100 105 110 115 120 125 130

0

2

4

6

8

10

12

A12 B22 B21 B20 B19

B18 B17 B16 B15

B14 B13

B12

A23 A22 A21 A20 A19 A18 A17 A16 A15 A14 A13

135 140 145 150 155 160 165 170 175 180 185 190 195 Time (min)

0

1

2

3

4

5

B34

B23

A27+B26

B33 B32 B31 B30 B29 B28 B27 B25 B24

A35 A34 A33 A32 A31 A30 A29 A28

A26 A25 A24

merged at start

merged once again

maximal separation

020219GK RECYCLE GC

MS-SIM separation of GC non separated isomers

020219GK 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

020219GK RECYCLE GC

recycle capillary GCCONSTRUCTION

peristaltic pump providing optimal column flow for columns from 5 to 50 meters

fixed end column splitter

020219GK RECYCLE GC

INSTRUMENTATION - interface IN RECYCLE CHROMATOGRAPHY

R1 40 m (injector)

R2 40 m (detector MS)

column flow

peristaltic pump

020219GK 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

020219GK RECYCLE GC

nonselective separation

Carbowax 20M300 m, 250 µm n = 500,000 n-dodecene isomers

020219GK RECYCLE GC

selectivity of separation

separation of isomers also with a functional group in middle of carbon chainn-dodecenes

020219GK RECYCLE GC

MS-SIM separation of GC non separated isomers

020219GK RECYCLE GC

ABOUT

CHARACTERISTICS

SEPARATION EFFICIENCY

RESOLUTION

RECYCLE CHROMATOGRAPHY HW

020219GK RECYCLE GC

NEW GC METHODS development

sample preparationefficiencyselectivityhyphenationsensitivitydetection

software

ITP - GCrecycle GCstationary phasescomprehensivethermal modulationspectral detectorsdeconvolution

toward reduced ultimate uncertainty