Investigation of the interaction of caffeic acid with surface of nanosized cerium dioxide by methods of thermodesorption mass-spectrometry and IR-spectroscopy
Journal Title: Хімія, фізика та технологія поверхні - Year 2018, Vol 9, Issue 3
Abstract
The study of the thermochemical properties of caffeic acid and its surface complexes is important for the pharmaceutical and food industries, medicine and for development of technologies of heterogeneous catalytic pyrolysis of the renewable plant biomass components. In this work, the structure of the surface complexes of caffeic acid on the surface of nanosized cerium dioxide was investigated using FTIR spectroscopy, depending on the degree of the surface coverage (0.1–1.2 mmol/g). Thermal transformations of surface complexes were studied using temperature-programmed desorption mass spectrometry (TPD MS). The analysis of the magnitude of the difference between the assymmetric and symmetric carboxylate stretches СОО- (...) and in case of monodentate coordination, between the C=O and CO stretches (...) was carried out. Based on the obtained values of D, it can be assumed that bidentate chelating complexes ( ≈ 72 cm–1), bidentate bridging complexes ( ≈ 110 cm–1), and monodentate bound complexes ( ≈ 236 cm–1) of caffeic acid are present on the nanoceria surface. In addition, complexes bound through the phenolic hydroxyl groups are present on the surface. This is due to the ability of the nanoceria to generate basic hydroxyl groups that are able to deprotonate the phenolic groups to form phenolates on the surface. The analysis of mass spectrometric data allowed identification of products of thermal transformation and suggested possible ways of forming 3,4-dihydroxyphenylethylene, pyrocatechol, and phenol from surface complexes of caffeic acid, the structure of which was confirmed by data of IR spectroscopy. The kinetic parameters of the phenol formation reaction were calculated. It was established that on the surface of CeO2 the decarboxylation, dehydration and decarbonylation reactions of caffeic acid occur effectively. These reactions are the desirable processes in biomass conversion technologies.
Authors and Affiliations
N. N. Nastasiienko, B. B. Palianytsia, M. T. Kartel, M. Larsson, T. V. Kulik
Keywords
Related Articles
- EP ID EP461639
- DOI 10.15407/hftp09.03.275
- Views 122
- Downloads 0
Selective dehydration of ethyl lactate into ethyl acrylate over NaY-faujasite
Dehydration of lactic acid and its esters is a promising way for obtaining acrylate monomers. The transformation of 10 % ethyl lactate solution in ethanol into ethyl acrylate over NaY, NaX, NaA and L zeolites has been st...
Хемихромные свойства пленок NiOOH в растворах формальдегида
С целью разработки сенсорных и электрохромных материалов исследованы оптические свойства пленок NiOOH в растворах формальдегида. Исследование кинетики оптических преобразований показали, что за счет их химического взаимо...
Синтез, структура і магнітні характеристики однодоменних наночастинок твердих розчинів (Fe1-xNix)Fe2O4
Синтезовано однодоменні наночастинки (НЧ) твердих розчинів (Fe1-xNix)Fe2O4. Досліджено їхню кристалічну структуру, морфологію поверхні і магнітні характеристики методами рентгенофазового аналізу, растрової електронної мі...
Influence of solid and liquid hydrophobic compounds on characteristics of water located in an adsorption layer of a hydrophilic component of the system
The aim of this study was to analyze the temperature and interfacial behavior of water bound to A-300, A-300/AM1 and Al2O3/AM1 initial and mechanically treated and located in air, chloroform alone or with addition of tr...
Influence of thermolysis in the nitrogen medium on physicochemical properties of medical using material based on biogenic hydroxyapatite
Physicochemical properties and adsorbtion activity of biogenic hydroxyapatite-based (BHA) osteoapatite material and BHA alloyed by ferromagnetic particles due to using two methods of physicochemical mixing with subsequen...