Actually I am getting trouble in isolating clear crystals. Since it is present in the charcoal like burnt material, it always comes with crystal, even with very careful separation. I have tried to wash it with water, acetone and solvent which I have used, but still not able to get only crystals. I can't use other solvent because it is soluble and also I have very less yield. I have to submit the sample for TGA, will my result will be affected due to presence of these trace impurities.
I disagree. While the qualitative plot are of course unaffected by impurities, the quantitative analysis is obviously biased, unless you can quantify the impurities with some other method. Melting point is not so useful, as it is not accompanied by any weight loss of course. Boiling point would be useful, though you have to make sure (thorough a DSC analysis perhaps) that no other reaction is taking place during the temperature scan.
Hi, your result will not be affected by the presence of impurities but surely you will be able to differentiate between your crystals and the impurity as you will obtain separate peaks of both provided you know the melting peak of your crystal!
I disagree. While the qualitative plot are of course unaffected by impurities, the quantitative analysis is obviously biased, unless you can quantify the impurities with some other method. Melting point is not so useful, as it is not accompanied by any weight loss of course. Boiling point would be useful, though you have to make sure (thorough a DSC analysis perhaps) that no other reaction is taking place during the temperature scan.
It depends. Do you have any idea of the amount of impurities? Above certain concentration, I belive that you'll have some problems. I agree with Piero.
If your sample contains impurity it will definitely affect your TGA results. Suppose if you are recording % weight loss of mass of sample against variation in temperature then the weight loss will surely get affected by amount of impurities present in the sample. Also if with increase in temperature the impurity can affect the properties of your compound of interest and you will not get correct results.
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