Chapter 8 Liquid Chromatograph 8.1 Introduction High pressures High speed High performance High sensitivity
Chapter 8 Liquid Chromatograph 8.1 Introduction High pressures High speed High performance High sensitivity
8.2 Principles 1. Classification (lIquid- Solid chromatography Adsorption process Xm+nSa一Xa+nSm XIS
8.2 Principles Adsorption process Xm + n Sa Xa + n Sm (1)Liquid – Solid chromatography n m a n a m X S X S K = 1.Classification
(2)Liquid- Liquid Chromatography Partition Process Xm XS K 、n S
(2) Liquid – Liquid Chromatography Partition Process Xm Xs K k m s s m v v C C = =
(3)lon Exchange Chromatography X++ Y(resins)+- Y*++ X(resins) R/- resin xm [Y-resin
(3) Ion Exchange Chromatography X+ + Y(resins) Y+ + X(resins) X Y resin X resin Y m m − − + + K =
(4)lon pair Chromatography ++YX+Y org XY K X
(4) Ion pair Chromatography a a K - O - X Y X Y + + = X+ a + Ya X+ Yorg
2. Column efficiency of LLC H=H,+H+H+im+H Eddy diffusion 2 Longitudinal diffusion
2. Column efficiency of LLC H = Hl + Hd + Hs + Hm + Hs m Hl = 2d p Eddy diffusion u C D H d m d = Longitudinal diffusion
Mass transfer c d D 2 72 2 SnL z An
u D C d H u D C d H u D C d H m s m p s m m m p m s s f s 2 2 2 = = = Mass transfer
H=A+ B Cu A =2nd B=CD 77 S snn
2 2 2 p m s m m m f s s d m p d D C D C d D C C B C D A d Cu u B H A = + + = = = + +
H H-U curve of gc and lc
H-U curve of GC and LC
3. Separation of Components (1)Resolution R R.1 O.5(X1+Y2) 7-19 (2 )Separation Factor 7-20
3. Separation of Components (1)Resolution R 0.5( ) 1 2 ,2 ,1 Y Y t t R R R + − = (2)Separation Factor 1 2 1 2 1 2 1 2 ' ' ' ' V V t t k k K K = = = = 7-19 7-20
