capillary flow technology – productivity …...capillary flow technology agilent restricted page 6...

Group/Presentation TitleAgilent Restricted

Month ##, 200X

Capillary Flow Technology – Productivity Enhancement

Tools for Hydrocarbon Processing GC Analysis

Jim McCurry Senior Applications Chemist Agilent Technologies

Presenter

Presentation Notes

There are many capabilities that have been used for years with packed columns that cannot be used with capillary columns and applications that have active compounds as analytes. If we could bring those capabilities to capillary columns, it would open up many new ways to solve difficult application problems in all fields where capillary gas chromatography is used.

Capillary Flow TechnologyAgilent Restricted

IF We Only Had A Technology That Provided Easy, Reliable Flow Structures In The GC Oven...

It would open up many new (and old) capabilities for GC– Column connections (connect pre-column) – Change MSD columns (without venting) – Backflush (Reverse flow through column)– Detector splitter (effluent split to two or more detectors)– Merge flows (2 columns to 1 MSD) – Deans switch (heart cut select peaks to 2nd column)– Comprehensive 2-D GC (cut all peaks to 2nd column) – etc.

Presenter

Presentation Notes

There are many capabilities that have been used for years with packed columns that cannot be used with capillary columns and applications that have active compounds as analytes. If we could bring those capabilities to capillary columns, it would open up many new ways to solve difficult application problems in all fields where capillary gas chromatography is used.


Metal Fittings

Press Fit Glass

Graphite

Polyimide

Packed columns, reliable

Low dead volume, inert, low cost

High temperature

Low initial leakage

Types of Connectors Used In The GC Oven

Not inert, no ferrule for capillary columns

Difficult to assemble, comes apart

Sheds active graphite particles into sample path

Loosens and leaks with oven cycling, solvent tailing

Advantages Limitations

Presenter

Presentation Notes

Listed here are most of the technologies that have been tried for making connections inside the GC oven. While they all have some useful features, they all have limitations that prevent them from meeting the needs of capillary column applications.


Challenges For Inside the Oven Devices

– Inertness (it is in the sample path)– Low dead volume (it is in the separation path)– Leak free (especially with repeated temp cycling)– Fast thermal response (follow rapid oven ramping)– High temp tolerance (GC oven can go over 350C)– Reliable and easy to use

Presenter

Presentation Notes

These are the desired characteristics for any technology to be used for capillary applications.


5 Key Developments in Capillary Flow Technology

Complex flow structures with low thermal mass

Makes metal surfaces as inert as column

Backflushing now possible, change MSD columns without venting, known column outlet pressure

Accurately predict flows and pressures BEFORE installing devices

Easy to use, do not loosen or leak with oven cycling to 400°C

Manifold Plates

Deactivation of Metal

EPC

Calculators

Metal Ferrules

Presenter

Presentation Notes

These are the five key developments that form the foundation of Agilent’s capillary flow technology. All of these advancements were required to solve the problem of making reliable, easy to use flow structures for use inside the GC oven.


Capillary Flow Technology- Design

• Photolithographic chemical milling for low dead volume

• Diffusion bond two halves to form a single flow plate

• Small, thin profile provides fast thermal response

• Projection welded connections for leak tight fittings

• Deactivation of all internal surfaces for inertness

… a proprietary Agilent Technology

Presenter

Presentation Notes

The heart of the capillary flow devices is Agilent’s proprietary diffusion bonded plate technology. A special grade of stainless steel is polished and coated with a mask. Photolithography is used to remove the masking agent wherever a feature is to be etched into the surface. A precisely controlled acid etch is then performed to create the flow channels and through holes in the plate. The two halves of the plate are then folded together and heated to higher than 1000°C under very high pressures. This results in the two halves bonding together (diffusion bonding) to form a plate with the etched flow channels inside.


The Metal Ferrule

Square cut is not critical

Seal region

Does not loosen (leak) even with thousands of runs to 350CDoes not shed particles

Presenter

Presentation Notes

The Agilent metal ferrrule is key to the outstanding performance of capillary flow technology. The ferrule is pre-swaged to the fused silica tubing before cutting. This simplifies installation and provides a seal that is leak free and remains so indefinitely.


3-Way Splitter With MakeupEffluent Splitter

(3 Way)

Column in

Aux EPC in Det1 out

Det2 outDet3 out

Presenter

Presentation Notes

Here is an example of an Agilent capillary flow technology device. It is a three-way effluent splitter with makeup gas and is usually used to split between an MSD and two other GC detectors. The dotted line in the diagram is the flow path inside the plate.


Capillary Flow Technology

Column 1 In

Restrictor 1

out to vent

Plate

Ferrule

Nut

Restrictor 2

or Column 2

Channel

Presenter

Presentation Notes

This slide shows a cross-section through the fittings in the three-way effluent splitter. Point out that the end of the column is located in a small very well swept chamber at the entrance to the plate. This design minimizes peak tailing.


Comparison of New Fitting with Polyimide Fitting

Polyimide Fitting

New Fitting

Exposure to polyimide and unpurged annular spaces is greatly reduced

Ferrule Ejector Hole

Presenter

Presentation Notes

These cross sections compare common polyimide fittings with Agilent’s new capillary flow technology fittings. In the polyimide fittings, solvent and analytes can become trapped in the annular space between the outside of the column liner (brown) and all the way back to the ferrrule (green). Trapping can also take place between the outside of the column and the inside of the column liner back to the ferrule. This trapping results in tailing, especially of solvents like toluene. Another important feature of Agilent’s capillary flow technology fitting is the ferrule ejector hole. Polyimide ferrules have a problem where they often stick in the fitting and are difficult to remove. The Agilent metal ferrules stick much less frequently and if they do, are easily ejected by pushing the end of a paper clip through the ferrule ejector hole. This action rocks the ferrule off axis and frees it immediately.


PolyimideFID directCapillary Flow fitting

Capillary Flow Technology fittings avoid tailing with small but well swept dead volume

1.1 1.15 1.2 1.25 1.3

0

1

2

3

4

5

6

Pentane test chromatogramFitting Design Minimizes Tailing

Presenter

Presentation Notes

This slide shows three overlaid chromatograms of a test mixture containing hydrocarbons run with 1) the end of the column connected directly to the FID, 2) the end of the column going through a polyimide fitting, and 3) the end of the column going through an Agilent capillary flow technology fitting. Because the Agilent fitting is designed to have its void volume well swept, the tailing introduced by the fitting is negligible. As seen in the slide, the tailing introduced by the polyimide fitting is much greater.


Capillary Flow Technology- Capabilities

Detector Splitting

Solvent Bypass

Heart Cutting (Deans Switch)

QuickSwap

Modulation (GCXGC)

Backflush

Presenter

Presentation Notes

This is a list of some of the capabilities now made available by Agilent’s capillary flow technology. We will now go over some examples of these.


Capillary Flow Technology DevicesUltimate UnionUltimate Union

7890 GC

Column

FID

Precolumn

Gas Sampling Valve

7890 GC

Column

FID

Tube to Connector

Tube Connector

Reliable precolumn connector

Easy valve to capillary column connector

Tube is 0.25 mm id and is deactivated

Presenter

Presentation Notes

Here are two of the simplest members of the capillary flow technology family. The Ultimate Union is a butt connector that can be used, for example, to connect a pre-column ahead of the analytical column. The tube connector is a length of 0.25 mm ID deactivated stainless steel tubing connected to a capillary flow technology fitting. This offers a simple and reliable way of connecting capillary columns to gas sampling valves.


Biodiesel Analysis by EN14105/ASTM D6584 Capillary Flow Technology Ultimate Union• Use 1 to 5 m, 0.53 mm

ID deactivated fused silica tubing

• Improves peak shape• Ultimate Union

– easy, robust connection

– deactivated– no-leak metal ferrule– optimized for high

temperatures

4.8 5 5.2 5.4 5.6

Glycerin

Butanetriol (istd 1)

No Retention Gap

1 m x 0.53 mm I.D. Retention Gap

Capillary Flow Technology Ultimate Union

Retention Gap In

Column Out

Inert, High Temp Metal Ferrule


Refinery Gas Analysis

Col 1: Propark Q 80/100, 0.5mCol 2: Propark Q, 80/100, 6ftCol 3: Molsieve 5A, 60/80,2mCol 4: DB-1, 2m, 0.32mm, 5um

Col 5:HP-AL/S 25m,0.32mm, 8umCol 6:CarbonPLT 15m,0.53mm,3umCol 7:HP- Molsive, 15M,0.53mm,50um

Col 5

3rd TCD Channel Carry gas N2

301

301

301

FIDS/SL

A

1

2

3

4

5

6

1

2

3

4

5

6 TCD

TCD

12

3

4

567

8

9

10

outSample in

A

12

3

4

567

8

9

10

Out

Vent

S/SLB

B

FID Channel

TCD Channel Carry gas He

Col 1

Col 2

Col 3

Col 4

Col 6 Col 7


Column Union Connector

Enhance Gas Analysis with Ultimate Union

Traditional connecter

New Union connecter

…… Peak shape enhancementPeak shape enhancement


Application and Result- RGA standards

TCD Channel

Carry gas: He

3rd TCD Channel Carry gas: N2

FID Channel

25 uV

0500

100015002000250030003500

min0 1 2 3 4 5 6 7

CO

2

O2

N2

met

hane

CO

min1 2 3 4 5 6 70

25 uV

-100

0

100

200

300

400

500

H2

met

hane

pA

0200400600800

1000120014001600

min0 1 2 3 4 5 6 7

1-pe

nten

e

prop

yne

i-pen

tane

C6+

met

hane et

hane

ethy

lene

prop

ane

cycl

opro

pane

prop

ylen

e

i-but

ane

n-bu

tane

prop

adie

neac

etyl

ene

t-2-b

uten

e1-

bute

nei-b

uten

ec-

2-bu

tene

n-pe

ntan

e

1,3-

buta

dien

e

t-2-p

ente

ne2-

met

hyl-2

-but

ene

c-2-

pent

ene

The complete analysis with one injection in 6 minutes


Splitters: Unpurged Tee

1:1 split FPD:uECD

Effluent Splitter WITHOUT Makeup

Auto-sampler

7890A GC

Column

0.3 m X 0.25 mm id

30 m X 0.25 mm id X 0.25 um HP-5MS

FPD P

μECD

Simultaneous detection with 2 detectors (but NOT MSD)

No external pressure source - Cannot do backflushing

Det 2 OUT

Column IN

Det 1 OUT

Presenter

Presentation Notes

The unpurged tee is a splitter without makeup gas that can be used to split the column effluent to two different GC detectors. It is much more reliable than glass press fit connectors. Because it has no make up gas, it is not recommended for use with MSDs and backflushing cannot be performmed. It is of course also useful anywhere a low-volume tee connection is required in the oven.


QuickSwap

MSD TransferlineAuto-sampler

7890A GC

Column

AUX EPC4 psig

171 mm X 0.121 mm id restrictor

5975C InertMSD

Change MSD columns without ventingBackflush heavy components out split vent

Presenter

Presentation Notes

Quickswap is a capillary flow technology device used at the inlet to the MSD. It has a restrictor that is located inside the MSD transfer line. The pressure is maintained constant by Aux EPC and since the transfer line is at constant temperature, the flow into the mass spec is also constant. Quickswap is intended to provide two functions: 1) to allow changing columns and liners without venting the MSD and; 2) to allow backflushing the analytical column at the end of the run.


QuickSwap MSD Interface

Remove column w/o venting– Air & H2 O blocked

Safe disconnection of column from inlet for inlet maintenance

– Reversed flow through column during inlet maintenance

Backflushing– Removes heavies from column

Maintain constant flow to MSD

(flow rates exceeding 2 mL/min require an MSD with Performance Turbo)

MSD TransferLine

Aux EPC In

Column Effluent

Presenter

Presentation Notes

Self explanatory


Backflush with QuickSwap

S/S Inlet

QuickSwapColumn

1 psi

45 psi

MSD

Aux EPCSplit Vent Trap

During GC Run

After GC Run

S/S Inlet

QuickSwapColumn

25 psi

4 psi

MSD

Aux EPCSplit Vent Trap

Presenter

Presentation Notes

During the GC run the column flow combines with makeup flow from the Aux EPC and enters MSD. After all analytes have eluted, while holding at the final oven temperature, the inlet pressure is dropped to 1 psi and the Aux EPC is increased to a high value, in this case 45 psi. This reverses the flow through the column and sweeps any remaining heavy materials out through the split vent.


Benefits of Backflushing

– More samples/day/instrument– Better quality data– Lower operating costs– Less frequent and faster GC & MSD maintenance– Longer column life– Less chemical background

Presenter

Presentation Notes

self-explanatory


Three Other Devices Provide Backflush Capability

22--Way Splitter with Way Splitter with MakeupMakeup

33--Way Splitter with Way Splitter with MakeupMakeup

Deans SwitchDeans Switch

Presenter

Presentation Notes

Here are three capillary flow of technology devices. Since they all have make up gas provided by an Aux EPC, they can all be used to do backflushing when used with an inlet that can be backflushed (like the S/SL and the PTV).


Dean Switch

Cut

Deans Switch

Auto- sampler

7890A GC

FID1 FID2

Column 1 Column 2

Heart cutting 2-D GC provides extremely high chromatographic resolution

Presenter

Presentation Notes

The Deans switch is a capillary flow technology device that directs the effluent of the column to one of two ports. Its main applications are in solvent venting for detectors and for heart cutting 2-D GC. Heart cutting 2-D GC is an extremely powerful technique where analytes are first separated in column 1 and then the analytes are cut to a second column with a different stationary phase. Interferences that elute with the analyte in the first column are separated from the analyte on the second column. This provides a simple system to obtain extremely high chromatographic resolution. For analyses that require the separation of a few analytes (usually less than five), the resolution is so high that often a simple detector like an FID can be used in place of a more sophisticated detector like an MSD. When the technique is combined with a detector like an MSD, analyses that require, for example GC/MS/MS, can be accomplished with a standard benchtop quadrupole mass spec.


Heart Cut to Column 2

Trace Sulfur Compound(4,6-DMDBT)

Column 1 - FID 1

Column 2 – FID 2

0 2 4 6 8 10 12 14 16 18 min.

Hydrocarbon Matrix

Diesel Fuel

2-D Separation of Sulfur Compound in Diesel Fuel

Compound is completely resolved and can be analyzed with FID

Presenter

Presentation Notes

The top chromatogram is from the HP-5 column. The 4,6-Dimethyldibenzothiophene is cut from 6.40 to 6.65 min. The bottom trace is the Innowax chromatogram from FID2. The analyte peak is completely resolved from the other compounds that coelute with it on the HP-5. After calibration with a standard, the 4,6-Dimethyldibenzothiophene was measured to be 165 ng/uL with the 2-D system vs 162 ng/uL with the AED system. The detection limit of the 2-D method is in the low ppm range and comparable to that of the AED. For the analysis of this specific compound, the 2-D system is a less expensive and simpler solution than GC-AED, GC-SCD, or GC-MS. Note that the FPD cannot be used for this analysis (due to quenching) unless a Deans setup is used to separate the hydrocarbons from the analyte first.


Configuration for Enhanced ASTM D6584

ASTM D6584 measures trace hydrocarbons

• uses alumina PLOT column

Oxygenates best separated on HP-Innowax column

Use Deans switch to combine two methods into one

• primary column separates oxygenates

• Deans switch selectively transfers only the hydrocarbons to alumina PLOT

• HP-Innowax column protects alumina PLOT from damage

Capillary Flow Technology Deans Switch

PCM

FID 1

Inlet

FID 2

Restrictor

Primary Column HP-Innowax

(30m x 0.32mm ID x 0.5 um)

Secondary Column HP-Alumina PLOT “M”

(30 m x 0.53mm ID x 15um)

Presenter

Presentation Notes

ASTM method D6159 uses an alumina PLOT column for trace hydrocarbons in ethylene. Polar, oxygenated compounds must also be measured, but these can damage the alumina column. Therefore a separate method must be run for the analysis of oxygenates. Using a Capillary Flow Technology Deans Switch, these two analyses can be combined into one method. The sample is first separated on a primary HP-Innowax column so that the hydrocarbons are resolved from the polar oxygenated compounds. The Deans switch then “heart-cuts” just the hydrocarbons to the alumina PLOT column where they are completely resolved. With this arrangement, any polar oxygenates in the sample are prevented from damaging the alumina column resulting in longer column life and less downtime.


Complete Separation of Oxygenates and Hydrocarbons

20

40

60

80

100

120

140pA

0 5 10 15 20 25 Min.

1

2

34

67 8

9 1011

121314

1516

PLOT Alumina “M” (19095P-M23)

20

25

30

35

pA

0 5 10 15 20 25 Min.

Cut time: 2.3 – 4.3 min.

5 (methanol)HP-Innowax (19091N-213)

C1 to C4 Hydrocarbons Separated on Secondary Column

Heart-Cutting 100 ppmV Impurities in Ethylene

Presenter

Presentation Notes

In the upper chromatogram, the polar HP-Innowax column does not retain the ethylene and other hydrocarbons. However, any polar, compounds such as methanol are held on the HP-Innowax. Using the Denas switch the hydrocarbons are transferred ans resolved on the alumina column. Make a point that the Agilent alumina PLOT M column provides more uniform separation of the hydrocarbons than the standard alumina PLOT column. Peak 3 is the ethylene


ASTM 7059 - Trace Methanol in Crude by 2-D GC

FID 1

S/S Inlet

FID 2

PCM

restrictor

Column 1 HP1

Column 2 GS-Oxyplot

Used to “heart cut”

alcohols from HP-1 column to Innowax


ASTM 7059 - Trace Methanol in Crude by 2-D GC

1 2 3 4 5 6 7 Min.-0.5

0

0.5

1

1.5

Second Column (Oxyplot) –

FID2

Crude Oil Hydrocarbons

Methanol

(10 ppm)

1-propanol

(500 ppm

ISTD)

backflush

1 2 3 4 5 6 7 Min.0

100

200

300

400

500

600 Cut time:

1.70 –

2.35 min.

Crude Oil Hydrocarbons

Primary Column (HP-1) –

FID1

backflush

pA

pA


FID A

S/S Inlet

FID B

PCM

<< 1mL/min

purgerestrictor

OffHigh boilers

Restrictor

HP-1

GC-Oxyplot

Backflush To Decrease Run Time

Valve off –

Lower Inlet pressure, Increase PCM pressue

Split vent

(high boilers)

11.14 psi9.78 psi<0.5 psi >60 psi


Agilent’s flow modulator design : Differential Flow

ModulationValve

FID

Split/SplitlessInlet

Column 1 (25 – 30 M)

Column 2 (5M)

Collection channel

Flow Modulator

H2

Flush Flowdirection

Collect Flow direction

Flow modulator eliminates the need for cryo. Sample compression controlledby flow ratios occurs in the collection loop and is quickly injected into the second column, resulting in very narrow and tall peaks.

Differential flow concept is designed by John V. Seeley, Oakland University

Presenter

Presentation Notes

GC x GC or 2D GC is a relatively chromatographic technique for analyzing complex mixtures. Most systems today employ thermal modulation devices to focus the effluent from the first column before injection into the second. This required large amounts of cryo. Through use of differental flow the use of cryo is avoided. This very small and simple device, based again on capillary flow technology has an integrated collection channel to take effluent from the first column and with a switch in the 3 way solenoid valve “inject” it quickly into the second column with a signal enhancement proportional to the flow rate difference in the two columns (typically 20 to 1). Peak widths at half maximum are typically 60 to 100ms. The modulation cycle approximately 1.5 seconds. 1.4 seconds with the modulation valve directing flow in down arrow direction (refer to diagram) and 0.12 seconds with the modulation valve directing flow in up arrow direction (refer to diagram) An FID running at 200 Hz is used to integrate the fast peaks that elute in each 1.5 second modulation. Hydrogen carrier gas is used for speed. Column 1 is typically non polar and column 2 is typically a DB WAX or DB INNOWAX.


Flow modulation: (GC x GC) of diesel fuel: 7890A

GC x GC Chromatogram:• Showing the normal B.P. distribution (1st dimension)• Also shows hydrocarbon classes in clusters

• Consistent RT for alkanes in 1st dimension showing precise modulation• Comparable peak in 2nd dimension band shows minimum peak broadening

with flow modulation

Naphthalene

Toluene

p-xyleneo-xylene

C9 C12 C16

Alkanes

mono-Aromatics

di-AromaticsMethyl-naphthalenes

Presenter

Presentation Notes

The diagram shows GCxGC data that has been processed in the GC Image software (Zoex Corporation). This sample of diesel fuel clearly shows hydrocarbon class separations. Alkanes, mono-aromatics and di aromatic are separated from each other in the 1.5 seconds available on the second column. The entire run takes only about 27 minutes.


Agilent Flow Modulation GC x GC

• Reliable Setup: Based on capillary-flow- technology, easy to setup, high

performance chromatography, and reliable.

• No Cryogen Required: Flow modulation means no tanks of Liquid N2 or CO2

• 7890A Enabled GC x GC: Capillary- flow-technology ready, synchronized

periodic events ensure precise modulation, control from a modified TCD board

• Comparable resolution without Liquid N2: Cap Flow Technology allows low

dead volume and precise flow control, resulting in minimum peak broadening even

without cryo-focusing . Peak widths on the second column are typically 70 to 100 ms

at half maximum.

• Sensitivity: Approaches that obtained by thermally modulated systems

Presenter

Presentation Notes

Flow modulation, based on a unique deactivated capillary flow technology device is easy to implement on the 7890A with control of modulation from on-board GC electronics. This implementation has no moving parts, and does not require cyrogenic fluid for focusing. Performance is comparable to thermal modulation although not as sensitive for trace analysis. Excellent peak shape that is critical for good performance on the fast second column is seen due to the lack of dead volume obtained through the use of capillary flow technology fittings. This approach to GCxGC has the potential to be adopted for routine use.


Capillary Flow Technology solves difficult application problems easily.

It opens up many new (and old) possibilities for GC and GC/MS systems.

Summary

Presenter

Presentation Notes

Self explanatory

capillary flow technology – productivity …...capillary flow technology agilent restricted page 6...

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