Transcript Xuan Wang CIT analysis in process

Analysis in ProcESS
Xuan Wang
Department of Chemical Engineering
Department of Metallurgy and Materials
Engineering
23/01/2013
Table of content
• Introduction
• ICP-MS
Introduction
 Principles
 Influence
 Sample preparation
AAS
FT-IR
PerkinElmer GC lab
Mercury Analyzer
Contact Angle Analyzer
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Introduction
ProcESS --- Process Engineering for Sustainable Systems
Research focuses on:
•Process intensification
•Solid waste treatment
•Surface and interphase analysis
•Advanced separation processes using membrane technology
Various analytical equipments:
ICP-MS, AAS, FT-IR, GC, Mercury Analyzer, Contact Angle Analyzer…
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ICP-MS
Inductively Coupled Plasma
-Mass Spectrometry
Producer: Thermo Scientific
Type: X series
Contact: Michèle Vanroelen
([email protected])
Advantages:
•Quantitative and semi-quantitative analysis
•Detection limits at or below ppt level for much of the periodic table
•8 orders of magnitude analytical range
•High productivity
•Isotopic analysis
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(PerkinElmer)
Remark:
Method Detection Limit (MDL)
is generally 2-10 times more than
Instrumental Detection Limit (IDL)
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PerkinElmer, Inc
RF Load Coils
ICP Torch
Principles
Argon Plasma
Ionization of atoms
At certain time, only ions with one
certain mass-to-charge ratio can
pass through and be detected.
Solid
Atoms
Ions
Aerosol
Gas
(PerkinElmer)
mass spectrometer
Cones
Schematic representation of a quadrupole ICP- MS
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Influence
• Matrix effects:
signal suppression or enhancement caused by overloading
of plasma, cooling effects, changes of ionization, blockage
of cones, change of ion sampling, etc.
Remedy: internal standard (Be, Ga, In, Tl).
Residual signal (rlative to the signal in 0.14 M HNO3)
for several elements present in 0.5 M H2SO4 matrix as
a function of the mass number of the nuclide.
(Vanhaecke F., Vanhoe H., Dams R., Vandecasteele C.
, Talanta, 1992, 39)
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Influence
• Spectral interferences:
interferences between ions with similar atomic mass.
Remedy: Use of HNO3
Select isotopes (65Cu instead of 63Cu (ArNa+))
Mathematical correction
Modify sample preparation
(USGS)
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Influence
• Cone blockage
The small orifice (~ 1mm) on the cones can be blocked if
too much total dissolved solids (TDS) in the solution. This
can cause decreased sensitivity and detection capability
Remedy: diluted feeding solution (TDS no more than 0.2%)
Partially blocked orifice
(Kym Jarvis. Presentation for Nuclear
Spectrometry Users Forum, May 2005)
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Sample preparation
Preparation
•Sample digestion
Three acids digestion
Microwave digestion
Lithium metaborate fusion digestion
•Sample dilution
•Standard preparation
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Sample digestion
• Three acids digestion


0.1 g finely ground sample added in Teflon beaker with
heating on the bottom and lid on the top
Three acids:
- HNO3: oxidation, dissolving oxides and hydroxides
- HClO4: oxidation, dissolving organics
- HF: dissolving silicate
are added, 5 ml each, by sequential order until the
previous one boiled down.
 If the sample is not completely dissolved, more cycles of
the process (without HClO4) are needed until the
complete dissolution of sample.
Caution: highly corrosive acids applied and protection needed
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Sample digestion
• Micro wave digestion:





Acid digestion carried out in microwave
transparent inert material vessels, where
pressure is introduced
High temperature (260-300 °C)
High digestion quality
Reduced acid consumption
Reduced digestion time (20-60 minutes)
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Sample digestion
• Lithium metaborate fusion digestion:
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
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Thoroughly mix 0.1 g finely ground sample with 1.0 g of
lithium metaborate (LiBO2)
Put the mixture in a graphite crucible and insert crucible
into an oven at 1000 °C for 15 minutes
Pour the melt mixture into 100 ml 5 vol% nitric acid
solution
Stir at least 15 minutes until all solid dissolved then
filtrate the solution for dilution and measurement
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Sample preparation
• Sample dilution:
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
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The digested solution normally need to be dilute
Concentration not larger than 1000 ppb
Concentration not lower than detection limit
Normally 2 vol% HNO3 is added
• Standard preparation:
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
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Chose concentration of elements according the element
concentration in diluted sample
Addition of internal standards (e.g. Be, Ga, In and Tl)
3 or 5 calibration points, including one blank
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AAS
• Atomic Absorption Spectroscopy
Principle: absorption of EM-radiation characteristic for
electron transition in the outer shell of an atom of an element.
(http://web.vscht.cz/poustkaj)
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AAS
• Measurement of almost all metals, metalloids and some
non-metals (B, Si, P)
• Sample:
- Solution in diluted acids
- Diluted biological fluids
- Suspensions of solid samples (slurries)
• Flame AAS (in CIT): measurement of higher concentration
(10-100 ppm) – high temperature flame (N2O)
• Measurement time 3-10 seconds
• Contact: Michèle Vanroelen
([email protected])
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FT-IR
• Fourier Transform InfraRed
• (with diamond ATR)
Principle: absorption of
IR-radiation results in
changes
of vibrational energy of
molecules.
(Thermo Nicolet, co.)
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FT-IR
• Identification of unknown pure (organic) compounds
• Identification of functional groups
• Sample: liquid, solid (in solution), solid.
• Fast measurement, in a matter of seconds
• Less suited for quantitative analysis, detection limits
around 2 %
Contact: Christine Wouters ([email protected] )
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PerkinElmer GC lab
•GC-MS
GasChromatograph Mass Spectrometry
Analysis of PCBs, phenols, trizaines, organophosphorus
and organochlorine pesticides, PAHs, mono-aromatic
hydrocarbons.
•GC-FID/ECD
GasChromatograph Flame Ionization Detector
and Electron Capture Detector
Analysis of PCBs, phenols, organochlorine pesticides,
mono-aromatic hydrocarbons, aspecific solvents,
mineral oil, volatile organic acids.
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PerkinElmer GC lab
•GC-FID
GasChromatograph Flame Ionization Detector
Analysis of phenols, mono-aromatic hydrocarbons,
aspecific solvents, mineral oil, volatile organic acids.
•GC-FID/NPD
GasChromatograph Flame Ionization Detector and
Nitrogen Phosphorus Detector
Analysis of phenols, triazines, organophosphorus
pesticides, mono-aromatic hydrocarbons, aspecific
solvents, mineral oil, volatile organic acids.
Contact: Christine Wouters ([email protected] )
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Mercury analyzer
• Design for all types of sample:
-Environmental samples
(water, soil, plants, etc)
-Human samples
(hair, blood, urine, etc)
•Vapour generation technique
(remove most chemical interferences)
(not operational yet by the moment,
part of RARE3 project)
•Atomic fluorescence spectrometry
(mercury analysis down to ppt level)
•Contact: Tom Van Gerven
([email protected] )
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Contact Angle Analyzer
KRÜSS Dsa10-MK2
Contact: Bart Van der Bruggen
([email protected] )
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Contact
• ICP-MS
• AAS
Michèle Vanroelen
([email protected])
• FT-IR
• PerkinElmer GC lab
Christine Wouters
([email protected] )
• Mercury Analyzer
Tom Van Gerven
• Contact Angle Analyzer
Bart Van der Bruggen
([email protected] )
([email protected] )
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Many thanks!
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