ACADEMIC RESEARCH IN MODERN SCIENCE
International scientific-online conference
144
CHROMATO-MASS-SPECTRAL ANALYSIS OF THE SYNTHESIZED
SUBSTANCES
Ruzikulova N.B.
Vapoev H.M.
Navoi State University
Navoi State Mining and Technological University
Email: ruziqulovagina4@gmail.com
https://doi.org/10.5281/zenodo.15752834
Annotation.
The composition of the raw materials used in the synthesis of
acetaldehyde, the catalyst CCF (cadmium calcium phosphate), was analyzed and
determined. Based on the analysis results, active cadmium oxide was isolated
from the KKF catalyst and new catalysts were prepared. Acetaldehyde and
acetone were synthesized from the prepared catalysts.
The qualitative and quantitative properties of the synthesized substances
were analyzed and confirmed by chromato-mass spectrometry methods.
Keywords:
Acetylene, water, acetaldehyde, acetone, CCF (cadmium calcium
phosphate), CaO, CdO, P
2
O
5
, MgO.
A mass spectrometer determines the mass and structure of a substance.
This step works as follows:
Each molecule ionizes (loses or gains electrons).
Ions move through an electric/magnetic field.
The device determines the mass-to-charge ratio (m/z) of ions.
The result is a mass spectrum - a graph showing the intensity and mass of
each ion.
In this method, each substance separated by chromatography is
sequentially sent to a mass spectrometer where it is detected. These two stages
are connected sequentially in one system.
Pharmaceutical - in the determination of pure or mixtures of medicinal
products,
criminalistics - in the detection of narcotic drugs or poisons,
ecology - determination of pollutants in air, water, soil,
food industry - used to detect preservatives or pesticides in food.
The obtained spectra were identified using the i-NIST standard library. The
composition of the studied sample was calculated based on TIC (Total Ion
Chromatogram) - total ion chromatogram data.
ACADEMIC RESEARCH IN MODERN SCIENCE
International scientific-online conference
145
Figure 1. Chromato-mass spectrum of acetaldehyde
Figure 2. Chromato-mass spectrum of acetone
The mass spectrum of acetaldehyde (Fig. 1) is characterized by the
following main peaks:
~29 -100% (main peak) [CHO]
+
fragment - most stable and widespread;
~44 - average peak, molecular ion [C
2
H
4
O]
+
- ionic form of the entire
molecule;
ACADEMIC RESEARCH IN MODERN SCIENCE
International scientific-online conference
146
~43 - upper peak [CH
3
CO]
+
- simple fragment, often found in ketones and
aldehydes;
~15 - Low [CH
3
]
+
- methyl group fragment.
The strongest peak in this spectrum is at m/z = 29, representing the [CHO]
+
fragment of the acetaldehyde molecule.
At the same time, the molecular ion peak at m/z = 44 confirms the total
mass of the substance.
The mass spectrum of acetone (Fig. 2) is characterized by the following
main peaks:
~43 - 100% (main peak) [CH
3
CO]
+
- this fragment is very characteristic of
ketones;
~58 - approximately 80%, molecular ion [C
3
H
6
O]
+
- whole acetone
molecule;
~15 - low [CH
3
]
+
- methyl fragment;
~29 - less intense [C
2
H
5
]
+
- ethyl fragment.
The peak at m/z = 58 indicates the molecular ion of acetone.
m/z = 43 is the main fragment, which is the most intense and stable
[CH
3
CO]+ ion in the spectrum.
Chromatography-mass spectrometry is a highly accurate, cost-effective, and
versatile technology for chemical analysis. It is one of the most reliable tools in
chemistry for structural, qualitative, and quantitative analysis of substances.
References:
1.
Vinarskiy V.A. Chromatography // Course of Lectures in Two Parts: Part 1.
Gas chromatography. Scientific and Methodological. Moscow 2003.- P. 172.
2.
Nifantev I.E., Ivchenko P.V. Practical Course of Nuclear Magnetic
Resonance Spectroscopy. Methodological development. Moscow. 2006.
- P. 13-197.
