Method of identifying ethylene glycol, propylene glycol and/or glycerin in aqueous solutions and/or a method for assessing their concentration in aqueous solutions

摘要

The notification shall cover the method of identification of ethylene glycol, propylene glycol and/or glycerin and the assessment of their concentration in aqueous solutions, which shall cover the following steps. The first stage is the preparation of 50% aqueous solutions of ethylene glycol, propylene glycol and/or glycerin and their precise mixing. In the second stage, spectrophotometric measurement is performed using the spectral FTIR spectroscopy 1200 -800 cm-1 at the resolution 4 cm-1 of the prepared aqueous solutions of ethylene glycol,propylene glycol and/or glycerin and the test sample. In the third stage, we compare the wavelength values of the sample peaks obtained with the standard wavelengths of peak waves characteristic of ethylene glycol, propylene glycol and/or glycerin. The fourth stage is the identification of the test sample and the fifth stage is the refractometric measurement of the aqueous solutions of ethylene glycol, propylene glycol and/or glycerin, distilled water,the test sample at a rate. 20oC using monochromatic light. Then, in the sixth stage, we have the calculation- from the obtained light refraction factor of ethylene glycol, propylene glycol and/or glycerin, the value of the refraction factor of the distilled water is subtracted, and each result obtained multiplies by 100. A graph of the calculated values is drawn up in the seventh and a linear regression equation is then determined for the collection of the results of the light refraction factors of ethylene glycol, propylene glycol and/or glycerin,favourably using a spreadsheet and read favourably to the second decimal place, the coefficient. In the last, eighth stage, the concentration of the test sample shall be calculated according to the formula below.