| Using density functional methods, the results of the analysis of traditional adsorbents and adsorbents based on nanosized
particles capable of trapping 1,4-dioxane and 2-methyl-1,3-dioxolane molecules in milk are presented. We considered the
following interacting compounds: 1,4-dioxane — primary amine, 1,4-dioxane — secondary amine, 1,4-dioxane — fullerene C20,
1,4-dioxane — a fragment of the structure of activated carbon, 2-methyl-1,3-dioxolane — primary amine, 2-methyl-1,3-dioxolane —
secondary amine, 2-methyl-1,3-dioxolane — fullerene C20, 2-methyl-1,3-dioxolane — a fragment of the structure of activated
carbon. We determined the optimal configurations of the corresponding interacting structures, estimated their binding energies
and chemical potentials. The highest binding energy was obtained for 1,4-dioxane adsorbed on C20 fullerene. At the same time,
the energy gaps between the occupied HOMO and unoccupied LUMO molecular states were calculated, which makes it possible
to characterize the reactivity and stability of molecules. Compounds of 1,4-dioxane and 2-methyl-1,3-dioxolane with amines
have rather large gaps HOMO-LUMO. Using the concept of the electronic localization function, we found that a covalent bond
is formed between 1,4-dioxane and C20 fullerene with a sufficiently high degree of electron localization in the bond region.
In other cases, the value of the localization function indicates the absence of a chemical bond between the compounds. The
proposed study gives recommendations on the adsorption of 1,4-dioxane and 2-methyl-1,3-dioxolane for further solid-phase
microextraction, which will allow them to be found in milk by gas chromatography using a flame ionization detector. |