Carbon, sulphur, oxygen, nitrogen and hydrogen
These five elements are the most common in our environment, by close to 95% in total. This means that the pollution risk is very high. For analysis we use special equipment which protects the sample. Additives and melting-pots are also protected or burnt clean before analysing. The process varies from one to five minutes per sample.
The sample quantity needed is 2 g. In exceptional cases smaller samples may be used. We always duplicate the test in order to avoid contamination.
The samples to be analysed are prepared by drilling chips with degreased drills, or with pieces obtained by filing manually (O + H). With these instruments we are able to analyse practically every metal or oxidic material. The limitations lie in the supply of reference material.
Equipment
We posses the most advanced equipment for analyses of C, S, N, O and H in metals. Here we have the only combination instruments corrected for matrix effects. E g nitrogen cannot usually be analysed in a matrix with high oxygen content. But, with our equipment, we are able to do this, with methods mainly following ASTM E1019-05. We are accredited to analyse C, S and N in steel (and in Ni-base, during autumn 2008).
The principles for the analyses
C and S are analysed by a quick temperature raise from room level to 1.700 oC, using a high frequency kiln and a ceramic melting-pot. An accelerator is added to the sample, allowing the analyses to be completed in appr 1 minute. The melting-pots used are cleaned at 900 – 1.000oC in a separate kiln. Accelerators and other additives are protected through using small doses.
There are many applications. Our equipment can differentiate between organic carbon, soot, graphite, carbonates and some carbides. When e g analysing lime re soot from combustion, differentiated from carbonate in the lime or the level of organic carbon in burnt, un-burnt or hydrated lime. In coating, e g inside tubes, we are able to analyse the level of calcification and also, with other equipment which other elements the coating consists of.
We are also able to analyse free carbonic acid in e g re-chargeable battreies and, at the same time, identify hydroxide and graphite.
N, O and H are analysed in a resistance kiln or a Colpit-kiln (H), with an inert helium or an argon/nitrogen atmosphere. No additives are used but for refractory metals such as Ti. As additives precious metals, such as Ni, Sn and also Pt are used.
Mobile hydrogen – hydrogen released at a temperature less than 900oC – and also total hydrogen, may be analysed.
