How is the solubility of nitrates in the mixed acid after the nitration reaction determined?
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How is the solubility of nitrates in the mixed acid after the nitration reaction determined? Let’s discuss how many methods there are.
You are probably carrying out the nitration of organic compounds. After neutralization and quantification, the sample can be directly fed into a chromatograph (with higher precision); the external standard method can be used, but the error in the results depends on the performance of the instrument as well as the solubility of the sample
It is a nitrotoluene reaction. How to describe the sample’s dissolving capacity? Could you explain it in more detail? Thank you
The sample is neutralized to near-neutrality using a high-concentration base, depending on the acidity of the sample; baking soda can also be used for adjustment near the endpoint. After that, the volume is adjusted using a volumetric flask. A certain amount of the water sample is then taken and directly injected into the chromatograph (if there is concern that the salts in the sample may affect the chromatography, it is necessary to extract the sample with alcohol or acetone before injection, but the alcohol or acetone must first be calibrated). The solubility of nitrotoluene can be several thousand mg/L; for higher precision, an Agilent chromatographic capillary column can be used, although a packed column made of 10% SE30 on a silanized 101 support can also be used, though with slightly lower precision； If the concentration is low or the conditions are not suitable, you can also try the colorimetric method, namely the determination of aromatic nitrocompounds in wastewater (naphthylethylenediamine hydrochloride colorimetric method). Color measurement is carried out at a wavelength of 550; however, it is necessary to prepare a calibration curve in advance. The result will show all the colored aromatic nitrocompounds present. Consider the specific circumstances before deciding whether to use this method
Additionally, when sampling, it is necessary to prepare standard samples in advance based on the substance required; the external standard method is used, with generally around 0.5 microliters being injected
Performing a comprehensive analysis of spent acid indeed requires expertise.