Liquid Injection valve testing for Micro-GC adaptation - University … · 2012-11-27 · • Injection of alkane mixture in Fast GC configuration HPLIS • Direct connection of the

Liquid Injection valve testing for Micro-GC adaptation

IFPAC – 2012

Ramy Abou Naccoul, Ph.D. Claude Bernard University Lyon

*Claude Bernard University, LSA team – **SRA instruments, + IFPEN, France

LSA/TAP - IFPAC 2012 - Baltimore MD

V. Malicet*, I. Mokbel*, R. Cozic**, J. Jose*, F. Baco-Antoniali+

LSA/TAP - IFPAC 2012 - Baltimore MD

Context: needs of micro-analyzers and micro-sensors

Difficulties to implement on industrial sites and R&D laboratories, because of:

- Unsatisfactory accordance between analyzers and industrials needs

- Some laboratories techniques not adapted for in situ application

Problematic of the existing micro-analyzers and micro-sensors:

To analyze at the closest of the process, needs are:

- micro analyzers, micro sensors

- coupled with sampling microsystems

directly integrated into the process

Instrumentalists

Laboratories

Industries

LSA/TAP - IFPAC 2012 - Baltimore MD

How to answer to the needs for micro analysis?

Project “INnovAL”

INDUSTRIES (Arkema, Rhodia, Bluestar, Perstrop, IFPEN) Request – Validation - Optimization

LABORATORIES (University Lyon) Ecole des Mines (St Etienne)

Research

INSTRUMENTALISTS (SRA, EIF) Development & Industrialization

LSA/TAP - IFPAC 2012 - Baltimore MD

University of Lyon : Our contribution in the INnovAL Project: Development of liquid sampling-vaporization system for μGC Development of a μGC for on line analysis of liquid (available only

for gas analysis because of the temperature limit of the injector: < 100°C)

Optimization of micro-sensors

Density, particles ...

Comparison of the performance of the two online sampling/injection systems

• Heated Pressurized Liquid Injection System HPLIS (from SRA) • Rapid On Line Sampling Injector ROLSI (from EIF)

The comparison between the 2 valves is carried out using a synthetic mixture of n-alkanes and by studying:

• Chromatographic Repeatability • Existence of discrimination between the alkanes

Advantages and limitation of each sampling system

Function of : • Temperature • Pressure

LSA/TAP - IFPAC 2012 - Baltimore MD

The aim of the study : Find the most suitable liquid valve , optimize and couple to the micro-GC

Moving partCarrier gaz inlet

Cappillary

Vaporisation chamber

Carrier gaz outlet Cooling fan

Spring

Electromagnet

Soft iron Core

ROLSI valve

Specification : • Maximum operating pressure 300 bar • Maximum operating temperature 250 °C • Transfer line upstream the GC, 300°C • Adjustable injection volume

LSA/TAP - IFPAC 2012 - Baltimore MD

HPLIS

Specification : • Maximum operating pressure 80 bar • Maximum operating temperature 220 °C • Sample volume 0.06 μL • HStem 350 °C

LSA/TAP - IFPAC 2012 - Baltimore MD

Operating System

LSA/TAP - IFPAC 2012 - Baltimore MD

HPLIS Valve Response of the HPLIS valve as a function of the temperature of the valve chamber

(at constant injection pressure = 6 bar )

Oven

Initial temperature

Final temperature

Time

50 oC 1 min 40 oC/min 320 oC 30 min

Carrier flow 1.1 ml/min FID temperature 320 oC

Injector temperature 280 °C

LSA/TAP - IFPAC 2012 - Baltimore MD

Conclusion: discrimination between the alkanes due to the low t°C max of the valve chamber (joint)

PTFE joint were replaced by glass-PTFE joint

HPLIS Valve

Conclusion:

*Pressure dependence was observed

*increase of 1.7% of the peak area

per 1 bar of pressure increase (PTFE)

*no dependence when using

glass-PTFE

LSA/TAP - IFPAC 2012 - Baltimore MD

Response of the HPLIS valve as a function of the upstream liquid pressure: 15 to 40 bars

HPLIS and fast-GC HPLIS has been tested in fast-GC configuration in order to simulate the Micro-GC conditions

A synthetic mixture of n-alkanes is used at atmospheric pressure

Column DB-1 : L=20m, I.D=0.1mm, 0.1μm Carrier gas : Hydrogen

Conclusion: shorter time of analysis (12 minutes gain) but same discrimination phenomenon than with normal GC

LSA/TAP - IFPAC 2012 - Baltimore MD

ROLSI valve n-alkane mixture between n-C8 and n-C16 at different injection pressures

valve chamber : 230 °C Transfer Line : 240°C

Pressures : 16 – 25 – 38 – 75 – 100 bar

LSA/TAP - IFPAC 2012 - Baltimore MD Conclusion: Discrimination between the alkanes independent from liquid pressure

ROLSI valve Discrimination study versus the valve chamber temperature

Three temperatures were tested 180, 220, 250°C using a synthetic mixture of n-alkanes

LSA/TAP - IFPAC 2012 - Baltimore MD Conclusion: the temperature of the valve has no effect on the discrimination

ROLSI Vs HPLIS A synthetic mixture of n-alkanes between n-C8 and n-C38 is used to evaluate the

performance of HPLIS and ROLSI at different pressures and temperatures

LSA/TAP - IFPAC 2012 - Baltimore MD

HPLIS • Discrimination independent from injection pressure • Temperature limitation to 220°C (normal PTFE joints) • Temperature limitation to 300°C (PTFE-glass joints) • Contamination of the core

ROLSI • Discrimination independent from injection pressure • Temperature up to 250°C • Long transfer line • Adjustable sampling volume

Perspectives ROLSI

• Installation of the ROLSI valve directly on the GC injector, elimination of the transfer line

• Increase the temperature of the ROLSI’s injection chamber, isolation of the valve chamber from the core

• Injection of alkane mixture in Fast GC configuration HPLIS

• Direct connection of the valve to the column (bypassing the GC split injector) • Test of new gasket (based on Vespel) to increase pressure and heat of the valve:

decrease discrimination • Injection of high boiling point mixture (efficiency of the flash heating)

LSA/TAP - IFPAC 2012 - Baltimore MD

In the frame work of a PhD thesis : • Improvements of Rolsi and HPLIS valves • conception, built and trial of a new liquid injection valve and adaptation to μGC

How ?

Perspectives

LSA/TAP - IFPAC 2012 - Baltimore MD

Liquid injection

Valve

Micro GC

Micro G

C SRA

Moving partCarrier gaz inlet

Cappillary

Vaporisation chamber

Carrier gaz outlet Cooling fan

Spring

Electromagnet

Soft iron Core

Objective : Place the injection valve and the Micro GC on the ASTUTE platform from EIF

INNOVation pour l’Analyse en Ligne

Analysis in the heart of the process

CONFIDENTIEL

Acknowledgment

Instrumentalists

Laboratories

Industries

LSA/TAP - IFPAC 2012 - Baltimore MD

INDUSTRIES (IFPEN, Arkema, Rhodia, Bluestar, Perstrop) Request – Validation - Optimization

LABORATORIES (University Lyon) Ecole des Mines (St Etienne)

Research

INSTRUMENTALISTS (SRA, EIF) Development & Industrialization

Thank you for your attention