Methane. I search colorimetric tests like bromide water for methane detection. Does anyone know any?
Alexandre, there are no satisfactory colorimetric reaction for methane detection. Sorry if I disappoint you but the "Handbook on environmental analysis" above gives very old, tedious, expensive and non-precise way for CH4 detection after removal of O2, CO2, H2 from gas sample collected with following burning and detection of the formed CO2. Still there is a loss of methane (as solubilized gas) and potentially significant overestimation of results because of presence of other hydrocarbons and other VOC. This technique is VERY bad, believe me. Below I list several adequate methods that are acceptable:
- gas chromatography with flame-ionization or thermoconductivity detectors (the cheapest new instrument is ~10K$)
- infra-red spectrometry (5-10K$, but you can find a good used one for much less)
- mass-spectrometry (20 K$ and higher, but this is the best choice)
- various ad hoc gadgets, e.g. some handheld toys based on semi-conductor detectors developed for express detection of methane in coal mines (could be as cheap as $100 but it can measure only high concentrations of CH4).
- enzymatic techniques, e.g. by using enzymes specifically converting CH4 to formate and other products.
Good luck in your search,
NP
Thank you very much Nicolai.
Your awnser helps me a lot, but I am disappointed with the idea that don't have a simple presence/absence methane test with colorimetric approach like colour tests for pH and chlorine for pool water testing.
Best wishes,
Alexandre