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Elemental Analyzer Consumables
Our products are intimately involved with your samples
Scott Hughes, EA Consumables, Inc. Jon Davies, Elemental Microanalysis, Ltd.
Intimately Involved A lot of focus is on the laboratory instruments Things that cost a lot get a lot of attention Impressive and shiny for lab tours
The Big The Tenacious The Colorful
Intimately Involved Simple truth If you do not get complete conversion of your analyte to N2,
CO2, SO2, CO or H2, then the big expensive shiny “detectors” will not help you.
The instrumentation IS important. Has to provide: Ability to transfer sample Hot environment with a steady carrier flow Ability to add oxygen at correct time and place and …the “detector” does matter
Intimately Involved Analyzers and Consumables
Like the Chicken & Pig in making Breakfast The Analyzer participates The Consumables are intimately involved
Your sample and our products have an intimate relationship
Sample Encapsulation Combustion Aides-Reaction Blocking Oxidation Reagents Interference removal Reduction Absorption materials
Focus on the nature and applications of consumables for NC and NCS determinations
Sample Encapsulation Many Choices – Over 400 from Elemental Microanalysis Material – Tin, Silver, Nickel, Copper, Aluminum, Cellulose Form
Capsules: Pressed, Flat bottom smooth, round bottom smooth Boats, Pans, Disks/Squares, Cones
Size – 1.06mm to 32mm diameter Weight – Standard, light weight, ultra light weight Preparation – Standard, Pre-cleaned
Encapsulation Tin The “go to” encapsulation material Exothermically reacts with oxygen to help in the thermal
decomposition of the sample. Very pliable and easy to fold/work Issues
In situ carbon blank Tin oxide is corrosive to quartz at operating temperatures
Encapsulation Silver Typically used for oxygen determination, as there is no formation of an
oxide (at combustion temperatures) as is the case with tin Can tarnish in storage. Will be removed at 375oC. Also used for removal of inorganic carbon from sample by acid
fumigation or addition. No exothermic reaction. No ash, forms a silver melt in the reaction tube It is stiffer and not as easy to fold/work compared to tin Higher cost Big savings in the lightweight silver capsule options
HINT: Collect the waste. Can fund a wild lab party!
Encapsulation Aluminum Can be pre-combusted at 550oC to remove contaminants There is an art to get it to combust. Can inhibit full sample reaction.
Forms Pressed – Solids Pre-cleaned in sample well Smooth wall (flat or round bottoms) – liquids Disks/Squares/Cones – sticky, fibrous, big samples Evaporating cups – liquid reduction
Life Cycle of a Pressed Capsule Purchase of special purity foil of the
appropriate thickness and width
Life Cycle of a Pressed Capsule Purchase of special purity foil of the
appropriate thickness and width Feeds into custom made cutting/pressing
machine. Cuts round disk
Pin forms capsule in die
Ejects capsule to collection bin
Life Cycle of a Pressed Capsule Purchase of special purity foil of the
appropriate thickness and width Feeds into custom made cutting/pressing
machine. Cuts round disk
Pin forms capsule in die
Ejects capsule to collection bin
Waste is melted down and cast into ingots.
Life Cycle of a Pressed Capsule Purchase of special purity foil of the
appropriate thickness and width Feeds into custom made cutting/pressing
machine. Cuts round disk
Pin forms capsule in die
Ejects capsule to collection bin
Waste is melted down and cast into ingots.
Ingots are rolled into sheets suitable for the extruded smooth wall capsules
Life Cycle of a Pressed Capsule Purchase of special purity foil of the
appropriate thickness and width Feeds into custom made cutting/pressing
machine. Cuts round disk
Pin forms capsule in die
Ejects capsule to collection bin
Waste is melted down and cast into ingots.
Ingots are rolled into sheets suitable for the extruded smooth wall capsules
Ultra-Pure capsules get an additional solvent wash.
Weighed into final package.
Your sample and our products have an intimate relationship Sample Encapsulation Combustion Aides-Reaction Blocking Oxidation Reagents Interference removal Reduction Absorption materials
The path to N2, CO2, SO2
The combustion soup Organicish Sample + O2 + heat (~1,000oC) = Volatile combustion products CO, CO2, CH4,CO3,H2O,N2,NxOx,SO2,SO3,X-,HF
Block the formation of… Chemical Oxidation to CO2 Reduce Absorb
Combustion aides Added to sample Additional oxygen source at point of combustion Block undesired side reaction
Stable sulfides and carbonates Will fuse with alkali and alkaline earth oxides
Vanadium Pentoxide Toxic
Tungstic Oxide Powdered
Combustion aides Fine Powders
Niobium Pentoxide Added oxygen
Silver Oxide Added oxygen
Cobalt Oxide Added oxygen
Magnesium Oxide Added oxygen – bind F-
Sucrose For inorganic fertilizers
Carbon powder (high purity) as above
Tin powder Added heat
Your sample and our products have an intimate relationship Sample Encapsulation Combustion Aides-Reaction Blocking Oxidation Reagents Interference removal Reduction Absorption materials
Active Reagents, NC analysis
CE/Costech/Eurovector
Elementar Sercon/ Europa
Perkin Elmer
Chromium Oxide Copper Oxide Chromium Oxide Chromium Oxide
Cobaltous/ic Oxide, silvered
Lead Chromate Copper Oxide Silver Tungstate on Magnesium Oxide
(Silver Wool) (Silvered Copper Oxide)
Silver Vanadate
Silver wool Silver Gauze
Copper Copper Copper Copper
Silver wool Quartz chips Copper Oxide
Silver wool
Com
bust
ion
Red
uctio
n
Active Reagents, S or NCS analysis
CE/Costech/Eurovector
Elementar Sercon/ Eurpoa
Perkin Elmer
Tungstic Oxide Tungstic Oxide Tungstic Oxide on Zirconium Oxide
Tungstic Oxide on Zirconium Oxide
Copper Copper Copper
None Copper None None
Silver wool (cooler zone)
Com
bust
ion
Red
uctio
n
Not all the same Chromium Oxide
Key impurities in the Chromium Oxide can cause devitrification of quartz
Devitrification is accelerated in the presence of Na & P ions.
Most Cr2O3 is formed from sodium dichromate, so Na is always present
Elemental Microanalysis uses a different process to form Cr2O3 to results in lower sodium impurities.
After granulation, it is further heat treated to drive off other impurities
The results is much longer tube life
The tube on the left showed no signs of devitrification after 1,000 determinations.
Not all the same
Tungsten (VI) Oxide, Tungsten Trioxide, Tungstic Oxide These actually are all the same.
B1025 Tungstic Oxide, granular for Costech/Thermo/Europa Produced by reacting Scheelite (CaWO4) with HCl to form tungstic acid,
followed by decomposition to WO3
The material is tableted under very high pressure, and then ground to the appropriate size. Results is very dense material.
B1217 Tungstic Oxide, granular for Elementar Requires a less dense granular material Produced by reacting tungsten metal with oxygen at elevated
temperature. Results in a much less dense granule.
Your sample and our products have an intimate relationship Sample Encapsulation Combustion Aides-Reaction Blocking Oxidation Reagents Interference removal Reduction Absorption materials
Interference Removal Reagents Things to remove
Sulfur Cl, Br, I F H2O Oxidative help
Silver Wool/Gauze
Coboltous/ic Oxide Silvered
Copper granules silvered
Copper Oxide silvered
Silver Vanadate
Silver Tungstate/Magnesium Oxide
Magnesium Oxide
Lead Chromate
Iron Wool
Your sample and our products have an intimate relationship Sample Encapsulation Combustion Aides-Reaction Blocking Oxidation Reagents Interference removal Reduction Absorption materials
Reduction - Copper Available in many forms Copper Wires fine 0.5 x 4mm Copper Wires course 0.65 x 6mm Copper Granules fine 0.05 – 0.2mm Copper Granules standard 0.1 – 0.5mm Copper Granules course 0.3 – 0.85mm Copper wires highest purity for IRMS Electrolytic Copper Copper turning extra fine long strands Copper turnings fine long strands
Reduction – Copper Cu + O2 + NxOx + SO3 CuO + Cu2O + N2 + SO2
Cu + SO2 (lower temperature) CuS + CuO + Cu2O Surface reaction
More available surface area, more capacity
In general wrt capacity Granular > Wires
Fine > Standard > Coarse
An old penny > Electrolytic copper
“Normal Copper” has very low capacity Copper is first oxidized and then subsequently reduced
IRMS grade – longer reaction time
Your sample and our products have an intimate relationship Sample Encapsulation Combustion Aides-Reaction Blocking Oxidation Reagents Interference removal Reduction Absorption materials
Absorption Materials Water Magnesium Perchlorate
Regular and Indicating 25g can ship as a HazMat excepted quantity Gets hard when wet, can cause blockages
Sicapent (phosphorous pentoxide on inert support indicating) Very low water vapor pressure Most effective desiccant Good flow properties when wet – easy to remove Nobody likes to handle (forms phosphorous acid when wet)
Absorption Materials Carbon Dioxide Carbosorb (NaOH on support) EMAsorb (our version of Carbosorb – black to grey)
Soda Lime (mostly calcium hydroxide, some NaOH, and KOH)
All above are HazMats 25g bottles can be shipped under excepted quantity rules
Chromosorbs Polymers based on diatomaceous earth (mostly SiO2) P types have twice the density and capacity of W types Low blank for CNS so OK for liquid absorbant
Intimately Involved Conclusions For successful EA-IRMS determinations:
Complete conversion of sample into analyte gases Removal of interfering substances Reagents can be tailored for specific types of samples Preparation of the reagents has a significant effect on
effectiveness and life of the reagents. Chickens and Pigs can get along together Let just skip breakfast!
