Knauer AZURA SMB Pilot User manual

SMB systems
Instructions
Document no. V6675

AZURA® SMB system instructions V6775
2
Note: For your own safety, read the instructions and observe the
warnings and safety information on the device and in the instructions.
Keep the instructions for future reference.
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KNAUER Wissenschaftliche Geräte GmbH
Hegauer Weg 38
14163 Berlin
Germany
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Internet: www.knauer.net
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Article number: V6775
Version number: 1.1
Last update: 2019/01/15
This document contains confidential information and may not be
reproduced without written content of KNAUER Wissenschaftliche
Geräte GmbH.
© KNAUER Wissenschaftliche Geräte GmbH 2019
All rights reserved.
AZURA® is a registered trademark of
KNAUER Wissenschaftliche Geräte GmbH.
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Publisher:
Version information:
The information in this document is subject
to change without prior notice.
For latest version of the siinstructions, check our website:
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Table of contents
AZURA® SMB system instructions, V6775
Table of contents
1. Product information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Intended use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 AZURA® SMB system variants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2.1 AZURA® SMB Lab. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2.2 AZURA® SMB Pilot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.3 System configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.3.1 AZURA® SMB Lab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3.2 AZURA® SMB Pilot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Simulated Moving Bed principle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2 Elution chromatography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.3 True counter-current process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4 Simulated counter-current process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.5 Eciency and economic aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3. Scope of delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.1 AZURA SMB Lab System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.2 AZURA SMB Pilot System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4. Basic safety instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.1 Target group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.2 Safety equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.3 What must the user take into account? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.4 Warning notifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.5 Decontamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5. Symbols and signs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6. Unpacking and setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.1 Operating environment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.1.1 Space requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.1.2 General requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.1.3 Earthquake areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.2 Storing unopened shipping boxes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.3 Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.4 Power supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.5 Connecting the capillaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.6 Flow charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.7 Connecting system to computer via LAN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
6.7.1 Connecting the single devices to the computer . . . . . . . . . . . . . . . . . . . . . . . 20
6.7.2 Configuring the LAN settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
6.7.3 Connecting the cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
6.7.4 Configuring the router. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.7.5 Integrating the LAN into a company network . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.7.6 Controlling several systems separately in a LAN. . . . . . . . . . . . . . . . . . . . . . . 22
6.7.7 Remote control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Table of contents
AZURA® SMB system instructions, V6775
7. Star t-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
7.1 Initial start-up checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
7.2 SOP: SMB power-up and shut-down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
7.2.1 Power-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
7.2.2 Shut down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.3 SOP: SMB start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.3.1 Removing air, flushing/cleaning the SMB and cleaning columns . . . . . . . . . 26
7.3.2 Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
7.3.3 Flushing the system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
7.3.4 Washing one single column . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
7.3.5 Flushing all columns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
7.3.6 Washing all columns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
8. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
8.1 Software operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
8.2 Meaning of the LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
8.3 SOP: AZURA® SMB separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
8.3.1 Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
8.3.2 Starting the system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
8.3.3 Pausing the separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
8.3.4 Stopping the separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
8.4 Change Zone configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
8.4.1 From 2:2:2:2 to 1:3:3:1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
8.4.2 From 2:2:2:2 to 1:1:1:1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
9. Functionality tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
9.1 Installation Qualification (IQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
9.2 Operation Qualification (OQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
10. Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
10.1 First measures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
10.2 LAN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
10.3 Possible problems and solutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
11. Maintenance and care. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
11.1 SOP: Cleaning procedure for pressure release valves and connected tubings for
AZURA® Lab SMB. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
11.1.1 Zone 1 pump & zone 2 pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
11.1.2 Feed pump & zone 4 pump. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
11.2 SOP: Cleaning procedure for pressure release valves and connected tubings for
AZURA® Pilot SMB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
11.3 Maintaining the AZURA® Lab System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
11.3.1 P um ps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
11.3.2 VICI valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
11.4 Maintaining the AZURA® Pilot system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
11.4 .1 Pump s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
11.4.2 VICI valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
11.5 Decommissioning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
11.6 Transport . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
11.7 Storage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
11.7.1 Disconnecting the power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Table of contents
AZURA® SMB system instructions, V6775
12. Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
12.1 General system parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
12.2 Technical parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
12.3 Wetted materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
13. Chemical compatibility of wetted materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
13.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
13.2 Plastics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
13.3 Non-metals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
13.4 Metals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
14. Legal information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
14.1 Transport damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
14.2 Warranty conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
14.3 Warranty seal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
14.4 Declaration of Conformity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
14.5 Disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
15. Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
16. Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54

1Product information
AZURA® SMB system instructions, V6775
1. Product information
1.1 Intended use
Note: Only use the system for applications that fall within the range of
the intended use. Otherwise, the protective and safety equipment of the
system could fail.
Application Separation and extraction
Pharmaceutical chemistry Chiral compound (cis-trans phytol, stero-
ids, peptides, antibiotics, etc.)
Food chemistry Fatty acids, carbohydrate mixtures
(sucrose/molasses, fructose/glucose, etc.)
Biochemistry Phenylalanine, fermentation/cell culture
products (citric acid, sugars, antibodies,
enzymes, etc.)
Petrochemistry C8-Hydrocarbon (xylene/toluene, etc.)
1.2 AZURA® SMB system variants
1.2 .1 AZURA® SMB Lab
This SMB system is optimized for separation tasks on a scale of several
hundred grams. The standard configuration consists of four AZURA®
assistants ASM 2.1L with seven multi-position valves and four AZURA®
pumps P 4.1S as well as our user-friendly software PurityChrom® MCC
including required IT hardware.
Depending on the special requirements of every separation the SMB
system can be freely configured via valve switch (e.g. closed-loop, open-
loop) and is upgradable with detectors and flow meters.
Individual configuration is available on request.
Fig.1 System layout AZURA® SMB Lab (example)

2 Product information
AZURA® SMB system instructions, V6775
1.2.2 AZURA® SMB Pilot
The AZURA® SMB Pilot is designed for the separation of binary mixtures
on a hundred gram to kilogram scale and is typically used with columns
up to 50 or 100 mm ID. Its special emphasis is put on the continuous ope-
ration mode and highest productivity.
The SMB standard configuration consists of four AZURA® pumps P 2.1L
and seven 8-port multiposition valves integrated into four AZURA® assis-
tants ASM 2.1L. Our user-friendly software PurityChrom® MCC and the
required IT hardware are also included.
We oer several variations of the standard system configuration.
Fig.2 System layout AZURA® SMB Pilot (example)
1.3 System configuration
The standard AZURA® SMB systems consists of four pumps and seven
multi-position valves.
The devices are arranged as follows:
Three pumps (Extract, Ranate, Eluent) are placed inside the SMB
cycle.
The feed pump is placed outside the SMB cycle.
Four valves are placed at the pump outlets.
Three valves are placed at the pump inlets. The feed pump inlet is not
connected to a multiposition valve.

3Product information
AZURA® SMB system instructions, V6775
Fig.3 SMB design scheme
1. 3.1 AZURA® SMB Lab
Number of
columns
Max. flow
rate
Max. pres-
sure
Description Article no.
8 50 ml/min 130 bar Stainless steel A29000
Biocompatible (PAEK, ceramic) A29001
1.3.2 AZURA® SMB Pilot
Number of
columns
Max. flow
rate
Max. pres-
sure
Description Article no.
8500 ml/min 100 bar Stainless steel A29501
How AZURA® SMB works
System confi guration
The standard AZURA® SMB systems consists of
four pumps and seven multi-position valves.
The devices are arranged as follows:
•
Three pumps (Extract, Ra nate, Eluent) are
placed inside the SMB cycle.
•
The feed pump is placed outside the SMB cycle.
•Four valves are placed at the pump outlets.
•
Three valves are placed at the pump inlets. The
feed pump inlet is not connected to a multi-
position valve.
Due to this confi guration the SMB system can be
used very fl exible for many di erent separation
modes. Additionally to the process stability
AZURA® SMB systems are outperforming every
other SMB system on the market regarding ma-
terial and confi guration fl exibility as well usable
pressure range.
Schematic AZURA® SMB design
Feed Raffi nate
EluentExtract
Zone 3
Zone 2 Zone 4
Zone 1
Column
switching
direction
14
AZURA® SMB systems
KNAUER_Brosch_SMB_12do.indd 14 28.08.17 10:51

AZURA® SMB system instructions V6775
4 Simulated Moving Bed principle
2.1 Introduction
Due to the fast development of new compounds and the more preci-
se knowledge about them, there is an increasing demand for purified
products. In most cases, chemical syntheses produce a lot of side com-
ponents. Therefore, dierent separation steps have to be involved into
production processes.
The most established and theoretically described thermal separation pro-
cesses (e.g. distillation, extraction, crystallization etc.) can not be applied
to all separation tasks. Among new separation methods, the adsorption
chromatography is a very eective but expensive process. The principle
of adsorption chromatography was discovered in the last century. The
separation is caused by dierent anities of the compounds (dissolved in
a liquid) to a useful solid phase.
Applications of adsorption chromatography were limited to analytical
scale for a long time. In the analytical scale, the mixtures are very diluted
and the distribution of a component between liquid and the solid phase
can be described by linear relations.
In the last few decades, adsorption chromatography is more and more
applied to the preparative process scale, where higher concentrations are
used and the liquid-solid distribution of a component becomes non-line-
ar and concentrationdependent. The peak profile and the retention times
are changing, so that modeling is more complicated.
The most established chromatographic process mode is elution chroma-
tography. Due to the theoretical understanding of this mode, it is possib-
le to use it in a very large scale. The regime of elution chromatography is
a discontinuous one, i.e. only discrete amounts of a mixture can be sepa-
rated. For higher amounts, a continuous mode should be favored. For a
binary (or pseudo-binary) mixture, the SMB process (Simulated Moving
Bed) with conventional chromatographic columns is successful.
Only the general principles of SMB will be explained in these instructions.
2.2 Elution chromatography
Among the established industrial scale separation processes preparative
adsorption chromatography is more and more used. Some separation
task (e.g. the separation of enantiomers) can be solved only by chromato-
graphy. The basic principle of elution chromatography is shown in Fig.4.
Fig.4 Principle of elution chromatography
The chromatographic column packed with a solid phase (adsorbent) will
be permanently penetrated by a fluid phase (eluent) with a well defined
2. Simulated Moving Bed principle

AZURA® SMB system instructions V6775
5Simulated Moving Bed principle
interstitial velocity. At the time t0a well defined amount of the sample
mixture is injected into the column. Due to dierent interaction forces
of the mixture components and the adsorbent (dierent migration ve-
locities), a separation of the mixture into the pure components will take
place. At the column outlet the purified components can be detected and
collected. This is the general principle of chromatography.
In preparative chromatography, the column is highly overloaded and is
not sucient to completely separate the mixture into the pure compo-
nents. The peaks are overlapping. This is shown in Fig.5. An unspecific
detector would show only the sum of both components, while the single
components are detectable in combination with a specific detector.
Fig.5 Overlapping of peaks in preparative-scale chromatography
The reason for overloading the column is, that there are time sections (t1,
t2), where the components elute in the required purity with a high concen-
tration. Because of the higher concentrations smaller liquid volumes are
necessary to separate equal amounts of the sample, such that the sepa-
ration of the value added components from the eluent (e.g. in vacuum
evaporators) is much simpler and cheaper.
The overlapping part of the concentration profile shown in Fig.5 with a
lower purity than required can be recycled to the column inlet.
In elution chromatography pulses are injected into the column, which are
separated in time (left side of Fig.6).
Fig.6 Process mode of elution chromatography
While migrating through the column, these pulses are broadened, due to
axial dispersion and dierent migration velocities and they are separated