Can anyone give me some suggestions how can I measure the black carbon, organic carbon and elemental carbon from particulate matter with reference? How the black smoke carbon can be different from the black carbon?
Whatever definition you use, be it black carbon, elemental carbon, or black smoke, depends on the way you are about to measure. Although each measuring method attempts to measure the same fraction of PM, it is the physical principles behind them which defer and make the results incomparable. If you use an aethalometer, the carbon is measured in terms of blackness on a filter material through absorption (hence it is defined as black carbon), while a themal/optical analyzer measures the carbon indirectly by combusting it and measuring the CO2 (hence elemental carbon).
I agree with Celzard that Raman spectroscopy could give you valuable information on the molecular structure of the carbon particles, but it wouldn't give you a way to express the fraction in a quantitative way.
If you have no aethalometer or thermal/optical device to your disposal, you can also measure the reflectance of the aerosol loaded filter and compare it with a blank one. This method was used in earlier times to measure the 'black smoke index' (hence another definition) and can be easily converted in units of black carbon. I recommend you read the article of P. Quicey at following url: http://www.sciencedirect.com/science/article/pii/S1352231007008187
If you can separate enough of this black matter from the rest, I would suggest Raman spectroscopy, which is rather specific, depending on the nature of the carbon.
Alain
Whatever definition you use, be it black carbon, elemental carbon, or black smoke, depends on the way you are about to measure. Although each measuring method attempts to measure the same fraction of PM, it is the physical principles behind them which defer and make the results incomparable. If you use an aethalometer, the carbon is measured in terms of blackness on a filter material through absorption (hence it is defined as black carbon), while a themal/optical analyzer measures the carbon indirectly by combusting it and measuring the CO2 (hence elemental carbon).
I agree with Celzard that Raman spectroscopy could give you valuable information on the molecular structure of the carbon particles, but it wouldn't give you a way to express the fraction in a quantitative way.
If you have no aethalometer or thermal/optical device to your disposal, you can also measure the reflectance of the aerosol loaded filter and compare it with a blank one. This method was used in earlier times to measure the 'black smoke index' (hence another definition) and can be easily converted in units of black carbon. I recommend you read the article of P. Quicey at following url: http://www.sciencedirect.com/science/article/pii/S1352231007008187
As the black part of aerosol often referred to as black carbon (BC) in literature are principal light-absorbing species in the atmosphere, playing an important role in the aerosol climatic forcing, an adequate knowlegde of the reflectance and absorptance property is essential The best way to quantify them is by Optical Transmittance which I think is best achieved using an aethalometer with light at two different wavelenghts. You can have a look at this journal article - http://www.sciencedirect.com/science/article/pii/S1352231004005588. Best of luck.
If you are truly trying to measure Black Carbon, then you should use one of the operationally defined methods mentioned above, Aethalometer or photoacoustic method. What filter media are your samples on? This may significantly limit what analysis you can do. Magee has an instrument (OT21) that allows for bench top Aethalometer type attenuation measurements for sampled on filters of both quartz and teflon. That may be your best option.
Good luck.
The cheapest method is the "Black Smoke" method, in used at the moment in several African and Asian countries. Google or go for instance to the page of prof Philip Hopke here at Researchgate and you will find ways to make your own set up.
There is a rather good relation between the "Black Smoke" parameter and/or the absorption coefficient and "Black Carbon" as measured with the much more expensive instruments measured
typo in my previous entry:
last word should be "mentioned" iso measured
Questioner
Since you do not react here is a publication from your own region
http://cleanairinitiative.org/portal/sites/default/files/Hopke-P.K._2008_Urban-air-quality-in-the-Asian-region.pdf
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