How to measure the moisture content in ethanol containing HCL? ?
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I would like to ask how to measure the moisture content in ethanol containing HCL ? A moisture titrator won’t work; HCL will cause interference. . . .
If the water content is high, measure it using solvent distillation； If the water content is low, the sample is quantitatively mixed with an organic amine of known water content to neutralize the acidity of HCl, after which Kjeldahl titration can be used.
The Karl Fischer method should work.
After neutralizing it to neutrality, there should be no problem using a KF-1 moisture meter. But pay attention to the operational details. Otherwise, it will not be approved.
I’m sorry, I have a question: when neutralization occurs, salts are formed. Will these salts affect the titration? ? ?
First, how much HCL is present in your ethanol? Have you tried using a KF moisture meter for the analysis? Could the inaccurate results be due to the volatilization of HCL during weighing? If the moisture meter is unable to conduct the analysis, then use triethanolamine for neutralization; inorganic bases should not be used, as they can affect the accuracy of your results
Using a KF moisture meter should work, right? What’s the acidity level?
1. The source of the error is that chloride ions can be reduced. 2. It is recommended that everyone look into the principle behind Karl Fischer titration for determining moisture content. 3. The poster should provide information regarding the composition of each component, whether they are major or minor elements, as well as the specific amounts of hydrochloric acid and moisture present. If the acid content is high, neutralization will result in the formation of water. I need you to provide preliminary estimated figures, Old Yellow Ox
Can it be done using online analytical instruments? If so, infrared or ultraviolet spectrophotometers can be used for this purpose; I have relevant information on this. match_0@163.com
This post was last edited by zhxyahoo on 2010-12-15 at 13:35. For the phosphorus pentoxide method, when the substance is in gaseous form, an online moisture analyzer from German company DKS can be used; it is not affected by hydrogen chloride, offers high precision, and excellent reliability. If it’s in liquid form, and there’s hydrogen chloride present, I have no good solution.
After reading some of my friends’ replies, it seems that not many people have actually performed the Kjeldahl titration; and even those who have done it probably don’t have a deep understanding of its essence. The classic Kjeldahl titrant solution, due to its high content of pyridine, can tolerate small amounts of acid in the sample; pyridine being an organic base, it can neutralize some or all of the acid in the sample without producing water. If the sample contains a high amount of acid, a large proportion of pyridine solvent can be used, or a certain proportion of other organic amines can be added. Also, before posting on floor 10, take a look at the question posed by the poster: how do you use methods for measuring gases to analyze liquid samples?