[enrico]

Hello everyone,
I am a student of chemistry in Italy and I have to do solubility tests, in surfactant-water mixture, of carbon particles (deposits from the exhaust) resulting from the combustion of kerosene in helicopters . I have to collect data...so I decided to make graphs of the solubility by varying the concentration of the surfactant.My aim is therefore to dissolve these particles by using surfactants ... but I do not know how to make a reproducible solubility test .. I thought about the UV-Vis spectroscopy ... but I don't have any standard, and the mixture is too messy (hundreds and hundreds of compounds)... thanks for the help

[The_MD]

Could you perhaps try dissolving a known weight of the particles, filter the solution, dry the filter and weigh it?  Repeat with each different water/surfactant mix?

If the solids are too small to filter reliably, would a turbidity test work?  For each surfactant-water mixture you would need to test with increasing amounts of the carbon particles, thoroughly mixed.

A TOC test might also do the trick, although you will have to do a bit of mathematical trickery and/or standardization work before starting your actual test.  Specifically, you will need to know the percentage of carbon atoms within the particles, and the TOC of the surfactant. 

These methods might be a bit too rough for a university project, and you'll need to fill in the blanks I've left, but perhaps they will get you thinking in the right direction. I can't honestly tell you what test your tutor is thinking of.   

[marquis]

You might try looking up some of the standard carbon black tests.

Carbon black is used in polymers (usually rubber).  There are a large number of standard tests.

It sounds like your carbon particles are similar in size.

Good luck.