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By ana on Wednesday, July 21, 2004 - 11:45 pm:
Hello!
I have to determine methylamine and methanol amount in substance. I use AT 624 (30m 0.53 3mcm)column+FID and DMF as a solvent but methanol peak is overlaped with methylamine peaks. Anyway methylene amine gives 3 or 4 peaks.
Any suggestion how to separate peaks? Please urgent
ana
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By chromatographer1 on Thursday, July 22, 2004 - 05:26 am:
Don't use methanol and DMF together if possible.
Don't use DMF or DMAc as a carrier solvent. Try redistilled DMSO or perhaps Pyridine. Methyl cellusolve even.
Use chromosorb 103 packed column to separate peaks.
Don't use water as methylamine will convert to dimethylamine and ammonia.
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By ana on Friday, July 23, 2004 - 01:21 am:
Thank you for answer. What is happened if methanol is determined and used DMF as a solvent?
ana
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By chromatographer1 on Friday, July 23, 2004 - 08:39 am:
It depends upon the concentration and the temperatures used in the injection port and analytical column.
Do linearity of recovery if you use the two solvents together. Don't assume one level accuracy will carry over to other levels, lower or higher in concentration.
Hello!
I have to determine methylamine and methanol amount in substance. I use AT 624 (30m 0.53 3mcm)column+FID and DMF as a solvent but methanol peak is overlaped with methylamine peaks. Anyway methylene amine gives 3 or 4 peaks.
Any suggestion how to separate peaks? Please urgent
ana
-------------------------------------------------------------------------------------------------------
By chromatographer1 on Thursday, July 22, 2004 - 05:26 am:
Don't use methanol and DMF together if possible.
Don't use DMF or DMAc as a carrier solvent. Try redistilled DMSO or perhaps Pyridine. Methyl cellusolve even.
Use chromosorb 103 packed column to separate peaks.
Don't use water as methylamine will convert to dimethylamine and ammonia.
-------------------------------------------------------------------------------------------------------
By ana on Friday, July 23, 2004 - 01:21 am:
Thank you for answer. What is happened if methanol is determined and used DMF as a solvent?
ana
-------------------------------------------------------------------------------------------------------
By chromatographer1 on Friday, July 23, 2004 - 08:39 am:
It depends upon the concentration and the temperatures used in the injection port and analytical column.
Do linearity of recovery if you use the two solvents together. Don't assume one level accuracy will carry over to other levels, lower or higher in concentration.
