Dear colleagues,
i have performed the decoloration of MB using a photocatalyst but the COD experiment for all the samples read under range what is the wrong in my Experiment?
Best Regards
Huda
Your question is not clear. Since you did not provide any details, I can't tell you what is wrong in your experiment. Chemical oxygen demand is the amount of O2, required to oxidize MB to CO2. You need significantly less O2 to oxidize BM to transparent compounds. he decoloration of MBmm
Yurii V Geletii dear sir thanks for your reply here is what has happened with me
1. I have 5 samples of MB with the photocatalyst after being subjected to solar radiation and been centrifuged to remove the photocatalyst at time 0, 10, 15, 20 ,25 plus the D.W. Sample.
2. I added 2 microliter of each sample to the 15000 range COD vials
3. Digested it for 2 hrs at 150 C
5. Read the absorbance value
6. All the values have given me under range reading.
so what is the problem with my experiment, what I have done wrong
What is the under "range reading'?
Currently, most COD tests use potassium dichromate as the oxidant. Have you used it?
Yurii V Geletii yes sir it contains potassium dichromate, it is lovibond vials
Yurii V Geletii sir it means the value is under zero so the device can’t read it
use pure water as a sample. you are supposed to get zero. You might have a problem with calibration .