Paraffin is a white, waxy solid with a slight odor. It can be obtained from the waxy fraction of natural or artificial petroleum by cold pressing or solvent dewaxing, sweating and other methods.
Paraffin is a solid crystalline product extracted from petroleum. It is a mixture of hydrocarbons, i.e. hydrocarbons of different molecular weights. It is mainly composed of normal alkanes, and also contains some solid isoparaffins, cycloalkanes and a small amount of aromatic hydrocarbons. Commercial paraffin wax generally has a carbon number of 22 to 36, a molecular weight range of 360 to 540, and a boiling point range of 300 to 550 degrees Celsius. As the molecular weight, boiling point and melting point of paraffin increase, the number of n-alkanes in the composition decreases and the number of iso-alkanes and solid cycloalkanes increases. The chemical composition of paraffins of different crude oils also differs.
Poorly refined paraffin wax is harmful to the human body:
Yellow paraffin or poorly refined wax still contains trace amounts of non-hydrocarbon components. These complex Although it only contains trace amounts of sulfur, nitrogen, and oxygen organic compounds, it greatly reduces the stability of paraffin. Some condensed ring aromatic hydrocarbons in the small amount of aromatic hydrocarbons contained in paraffin wax are harmful to the human body. Therefore, as paraffin wax used in the food industry and medicine, the condensed ring aromatic hydrocarbons must be reduced below the specified index before it is allowed to be used.
Using a mass spectrometer to analyze certain paraffins in the laboratory, the chemical composition data of each fraction divided by the number of carbon atoms in the molecule showed that the fractions with a smaller number of carbon atoms in the molecule were all n-alkanes. , as the number of carbon atoms increases, the content of isoparaffins and cycloalkanes increases, and aromatic hydrocarbons in wax only appear in fractions with high carbon atoms. Therefore, when the refining conditions are the same, in general commercial paraffin wax, the content of condensed ring aromatic hydrocarbons in low-grade paraffin wax is lower than that in high-grade wax.
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