TPD MS Research Articles

Bimetallic NiFe nanoparticles deposited on hollow glass microspheres (HGMs) of various sizes for the catalytic hydrogenation of CO2

The composites based on hollow glass microspheres (HGMs) decorated with nanoparticles of nickel and iron oxides were prepared from the nitrate solutions with ultrasound treatment. Further exposition of these composites in a hydrogen-helium flow leads to the formation of nanosized bimetallic particles of Ni(80)Fe(20) (number in the brackets is estimated as wt%) that are effective in the catalytic reaction of CO2 hydrogenation to methane. Investigation of CO2 conversion was carried out under gas chromatographic control, and methane yield was evaluated for composites with 20 and 60 wt% of grafted bimetallic mass. The TPD MS method was used to study the processes of desorption of particles involved in the mechanism of methane formation. Textural and structural characteristics of as-prepared and post-reacted composites were examined using low-temperature nitrogen adsorption and X-ray diffraction methods.

Microwave properties of chlorinated viscose-based carbon fibers for X-band radars

Viscose-based carbon fibers (VBCFs) were chlorinated with CCl4 vapor to investigate the effect of chlorination temperature on their microwave properties. The maximum chlorine content of 2.0 mmol g−1 was obtained at 450 °C. TEM and SEM showed carbon nanostructures and surface morphology preservation, respectively. TGA and TPD MS confirmed the formation of carbon-oxygen and chlorine-carbon groups, including CCl3 groups. The prepared chlorinated VBCFs can effectively reflect X-band microwaves, with nearly constant reflection losses over a wide frequency range, and are characterized by minimum transmission losses of −22 dB.

The Role of Surface Complexes in Ketene Formation from Fatty Acids via Pyrolysis over Silica: from Platform Molecules to Waste Biomass.

Fatty acids (FA) are the main constituents of lipids and oil crop waste, considered to be a promising 2G biomass that can be converted into ketenes via catalytic pyrolysis. Ketenes are appraised as promising synthons for the pharmaceutical, polymer, and chemical industries. Progress in the thermal conversion of short- and long-chain fatty acids into ketenes requires a deep understanding of their interaction mechanisms with the nanoscale oxide catalysts. In this work, the interactions of fatty acids with silica are investigated using a wide range of experimental and computational techniques (TPD MS, DFT, FTIR, in situ IR, equilibrium adsorption, and thermogravimetry). The adsorption isotherms of linear and branched fatty acids C1-C6 on the silica surface from aqueous solution have been obtained. The relative quantities of different types of surface complexes, as well as kinetic parameters of their decomposition, were calculated. The formation of surface complexes with a coordination bond between the carbonyl oxygens and silicon atoms in the surface-active center, which becomes pentacoordinate, was confirmed by DFT calculations, in good agreement with the IR feature at ∼1680 cm 1. Interestingly, ketenes release relate to these complexes' decomposition as confirmed by the thermal evolution of the absorption band (1680 cm-1) synchronously with the TPD peak of the ketene molecular ion. The established regularities of the ketenezation are also observed for the silica-induced pyrolysis of glyceryl trimyristate and real waste, rapeseed meals.

Improving the technique of protecting concrete floors in poultry houses

The object of the study was concrete floors in a poultry house with different types of litter. The paper addressed the problem of reducing microorganism contamination of concrete floors in poultry houses to prevent biological corrosion. Corrosion of the surface of the concrete floor in the form of the formation of calcium oxalate monohydrate crystals was established by scanning electron microscopy; microscopic fungi: A. pullulans, F. sporotrichioides, and A. niger were detected. The TPD MS method established that concrete samples obtained in a room with straw lose moisture by 51.52 % more, with granules – by 342.42 % (р≤0.05), with shavings by 6.06 %, compared to control. CO from concrete samples is released less with sawdust litter by 86.40 %, with straw – by 83.49 %, with shavings – by 76.69 %, with granules – by 69.90 % (р≤0.05). The CO2 content in concrete samples from the room with sawdust was lower by 86.88 % (р≤0.05), with straw – by 55.73 %, with shavings – by 38.52 %, with granules – by 23.77 %, compared to control without litter. Microbiological studies have established that 48 hours after disinfection, the total number of colonies of microorganisms on a concrete floor with a sawdust litter likely decreased by an average of 90.19 %, straw – by 91.62 %, shavings – by 79.76 %, granules – by 82.88 % (р≤0.05), in the control – by 83.73 %. It can be argued that the disinfectant destroys microorganisms on the concrete surface regardless of the type of substrate. The peculiarity of the experiment was the use of scanning electron microscopy and TPD MS methods to study structural changes in concrete. The research is distinguished by the use of a powdered disinfectant to reduce microbial damage to a concrete floor with different types of litter. The results of the experiment could be used in the aggressive environment of poultry houses to reduce the impact on concrete structures

Mechanistic reaction micro-kinetics-based structure–activity relationships for palmitic acid hydrodeoxygenation over NiMoSx/Al2O3 catalysts

The kinetics of palmitic acid hydro-deoxygenation over sulfided NiMo/γ-Al2O3 have been described, including the gas–liquid–solid mass transport/surface chemistry in a magnetically-stirred batch reactor via temperature (225–275 °C), hydrogen pressure (30–70 bar) and catalyst loading (0.1–0.4 g) variation. Intermediates, the hexadecanol and palmityl palmitate, have been probed for a deeper physical understanding of mechanisms. Rates were used to show the impact of the continuum H2 thermodynamic phenomena, availability and coverages on the selectivity among the direct hydrogenation, hydrogenolysis and decarbonylation reactions through the role of H• formation dependent and independent changes. The system was reduced to 11 catalytic transformation steps, including 8 different molecular species, present in medium. Sequence is simulated to happen on the calculated functional number of active site structures, the activity of which was averaged, while the activation of H2 was supposed to initiate independently. The results of model integrate parameters, such as energies, constants and performance. Process was highly temperature-related, while H2 presence expressed linearly. Phases were characterized with temperature-programmed desorption analysis, coupled with mass spectrometry (TPD–MS) technique, transmission- (TEM), scanning electron microscopy (SEM), X-ray powder diffraction (XRD).

Functional surface homogenization of nanobiochar with cation exchanger for improved removal performance of methylene blue and lead pollutants

Biochar materials are good examples of sustainable adsorbents with appreciable recent interests and applications in water treatment. The disadvantage of using unmodified pristine biochars in water treatment is mainly related to the inhomogeneous distribution of various surface functional groups. Therefore, the current study is designed to functionalize and homogenize the surface of a selected nanobiochar with a cation exchanger using hydrothermal and solvothermal microwave irradiation. The adsorption behavior of immobilized Amberlite cation exchanger onto Cynara scolymus nanobiochar (ACE@CSNB) was compared versus the pristine Cynara scolymus nanobiochar (CSNB). ACE@CSNB was categorized as a typical mesoporous material (mean pore size = 2.238 nm) and the FT-IR spectra confirmed surface modification via two characteristic peaks at 1140–1250 cm−1 and 1030–1070 cm−1 for R-SO3− with S = O. The TPD–MS analysis of CSNB and ACE@CSNB referred to the presence of carboxyl, lactonic, and acid anhydride groups as well as phenolic moieties. The adsorption behavior of methylene blue dye and lead ions by ACE@CSNB was found much higher than those concluded by CSNB providing maximum adsorptive capacity values owing to the played clear role by Amberlite cation exchanger. Moreover, ACE@CSNB was efficiently regenerated and confirmed MB and Pb(II) removal with 92.26% and 1000 µmol g−1, respectively Finally, the removal efficiency values from three water matrices by ACE@CSNB biochar were characterized as 91.74–98.19% and 96.27–99.14% for Pb(II) and MB, respectively to refer to the validity and applicability of the investigated ACE@CSNB biochar for treatment of these two pollutants from real water samples with excellent efficiency.Graphical

Adsorption and thermal transformation of lignin model compound (ferulic acid) over HY zeolite surface studied by temperature programmed desorption mass-spectrometry, FTIR and UV–Vis spectroscopy

The adsorption of an aqueous solution of ferulic acid (FA) on protonic zeolites was studied. Three different types of zeolites and adsorption parameters (time, solid/liquid ratio, temperature and pH) were analyzed and optimized. The HY zeolite (SiO2/Al2O3 = 12) showed an adsorption percentage of 90% at 30 °C, 5 min, 10 g L−1 and pH ≤ 3. The adsorption complexes structures on the molecular adsorbates were determined by UV–Vis DRS and FTIR spectroscopies. The FA molecule interacted through phenol and carboxyl group forming monodentate and bidentate surfaces complexes (bridge and chelate). Temperature programmed desorption mass-spectrometry (TPD MS) has been used to study the decarboxylation, demethoxylation, and transalkylation processes during pyrolysis of FA surface complexes with the formation of carbon dioxide, 4-vinylguaiacol, methanol, methane, polyaromatic hydrocarbons, phenols and others.

Reducing the biogenic corrosion of concrete in a pigsty by using disinfectants

The object of this study is the regularity of changes in the biogenic destructive effect of microorganisms on the concrete structural elements of livestock facilities due to the use of the original liquid phase mixture of disinfectant based on aldehyde and surfactant. Microorganisms use construction materials as a substrate for growth and nutrition; they produce citric acid, which leads to a change in the composition and morphology of hydrated cement new formations. The composition of the microflora of the pigsty has been determined, and the minimum concentration of disinfectant based on glutaraldehyde and didecyl dimethyl ammonium chloride was found. By the TPD MS method, a decrease in the intensity of carbon dioxide (CO2) release in concrete samples during the heating of the sample to 900 °C was proved, compared to the control intact corrosion sample. Electron microscopy of concrete samples shows the presence of destructive changes and colonies of micromycetes. It was established that calcite was intensively released in the control sample of concrete, which retained its integrity and was not subjected to corrosion when heated to a temperature of 600 °C. Electron microscopy confirms the preservation of the homogeneous structure of concrete. The use of a disinfectant based on glutaraldehyde and didecyl dimethyl ammonium chloride at a concentration of 1 % destroys colonies of micromycetes, 2 % – the shell of microorganisms, and 3 % – biofilm. Treatment of concrete with a disinfectant at a concentration of 3 % destroys microorganisms Aspergillus fumigatus and Penicillium oxalicum, inhibits the process of biological corrosion of concrete, and strengthens the structure of concrete. The results of the experiment can be applied to inhibit the corrosion of concrete and extend the life of building structures made of concrete through the use of a disinfectant based on aldehyde and didecyl dimethyl ammonium chloride at a concentration of 3 %.

Detection of the synergetic influence of chemical and microbiological factors on the properties of concrete constructions at chemical plants during the long-term service

Long-term operation of reinforced concrete structures in the conditions of chemical enterprises has a powerful negative impact on the physical and chemical properties of concrete, which leads to its destruction. The aim of this research is to determine the effect of biological and chemical corrosion on concrete structures in the workshop for the production of titanium dioxide by the sulphate method and the storage of finished products. In particular, chemical production for the synthesis of titanium dioxide by the sulfate method causes the rapid course of chemical (acid and sulfate) and microbiological (thionic bacteria and microscopic fungi) corrosion processes. These corrosion processes reinforce each other according to a synergistic principle. As a result, temperature-programmed desorption mass spectrometry (TPD MS) and scanning electron microscopy have experimentally proven the presence and spatial localization of colonies of thionic bacteria and microscopic fungi in concrete structures. Correlations between the intensity of biochemical corrosion and the depth of damage to the microstructures of concrete structures have been established. Moreover, a change in the chemical composition of concrete in the workshop for the production of titanium dioxide (increased SO2 content and reduced CO2) and the formation of gypsum crystals (CaSO4 2H2O) as a result of the dissimilation of microorganisms was established. Also, in the storage room for finished products, calcium citrate crystals and a violation of the formation of calcium carbonate are formed in the surface layers of concrete. In addition, the results of the study can be used to develop antimicrobial and anticorrosive protective agents to stop the biochemical corrosion of concrete in a chemical plant

Adsorption of doxorubicin on the surface of magnetically sensitive nanocomposite Fe3O4/Al2O3/С

Fe3O4/Al2O3/С nanocomposite was synthesized and characterized by a complex of physicochemical methods. The completeness of carbonization was confirmed by the method of TPD MS, and the results of TEM, EDX and changes in the values of the specific saturation magnetization proved the formation of the structure of Fe3O4/Al2O3/С by the type of core-shell. According to the results of potentiometric studies, the characteristics of acid -basic centers were quantitatively and qualitatively assessed. The adsorption of Doxorubicin (DOX) on the surface of Fe3O4/Al2O3/С was performed and the adsorption process depending on the contact time, pH of the solution and DOX concentration was studied. The experimental results of kinetic studies were analyzed for compliance with of Boyd, Morris-Weber and Elovich the theoretical models, models of pseudo-first and pseudo-second orders. Langmuir and Freundlich isotherm models were used to model adsorption processes. Under the conditions of the experiment (pH = 5) active basic centers (С = 8.46⋅10−5 mol⋅g −1, Кі = 1.296⋅10−5 (рК = 4.887)). Adsorption processes occur by a mixed diffusion mechanism, limiting processes are intraparticle diffusion and chemisorption processes of molecular and ionic forms of DOX. The highest correlation coefficient was r 2 = 0.971, the correlation of theoretical and practical values of the adsorption capacity (A mg g −1) indicates the possibility of using the Freundlich model to describe the adsorption of DOX on the surface of Fe3O4/Al2O3/C. Desorption processes practically do not occur at pH 7.4 (change of value A from 30.56 to 30.12 mg g −1, which is − 1.83%), at pH 5 percent of desorbed DOX is higher − 2.88% (change in value A from 30.21 to 29.51 mg g −1).

Catalytic Pyrolysis of Lignin Model Compound (Ferulic Acid) over Alumina: Surface Complexes, Kinetics, and Mechanisms

Studies of the thermochemical properties of the important model compound of lignin-ferulic acid (FA) and its surface complexes are substantial for developing technologies for catalytic pyrolysis of renewable biomass into biofuels and lignin-derived chemicals as well as for bio-oil upgrading. In this work, the catalytic pyrolysis of ferulic acid over alumina was studied by temperature-programmed desorption mass spectrometry (TPD MS), in situ FT-IR spectroscopy, thermogravimetric analysis, and DFT calculations. We established that both the carboxyl group and the active groups (HO and CH3O) of the aromatic ring interact with the alumina surface. We calculated the kinetic parameters of formation of the main products of catalytic pyrolysis: 4-vinylguaiacol, guaiacol, hydroxybenzene, benzene, toluene, cresol, naphthalene, and PACs. Possible methods of their forming from the related surface complexes of FA are suggested.

Direct changing of structural, morphological and electrochemical properties of the sulfur-doped nano TiO2

The ability of the direct changing of structural, morphological and electrochemical properties of the sulfur-doped nano TiO2 is discussed. The factors affecting the changing of morphological and electrochemical properties of nano TiO2 under various sulfur amounts are described. By the X-ray fluorescence analysis, XRD, FT-IR, DTA and TGA, TPD MS, ad / desorption of nitrogen, SEM, TEM and EIS of the S-doped nano-TiO2 determined impact of the sulfur content on type of the water binding, conductivity and ability to charging. The correlation between changing capacitance and capacitance dispersion and mesopores amount was found.

Decarboxylation of p-Coumaric Acid during Pyrolysis on the Nanoceria Surface

Temperature-programmed desorption mass spectrometry (TPD MS) was used to study the pyrolysis of p-coumaric acid (pCmA) on the nanoceria surface. The interaction of pCmA with the CeO2 surface was investigated by FT-IR spectroscopy. The obtained data indicated the formation on the nanoceria surface of bidentate carboxylate complexes with chelate (Δν = 62 cm−1) and bridge structure (Δν = 146 cm−1). The thermal decomposition of pCmA over nanoceria occurred in several stages, mainly by decarboxylation. The main decomposition product is 4-vinylphenol (m/z 120). The obtained data can be useful for studying the mechanisms of catalytic thermal transformations of lignin-containing raw materials using catalysts containing cerium oxide and the development of effective technologies for the isolation of pCmA from lignin.

Catalytic Pyrolysis of Lignin Model Compounds (Pyrocatechol, Guaiacol, Vanillic and Ferulic Acids) over Nanoceria Catalyst for Biomass Conversion

Understanding the mechanisms of thermal transformations of model lignin compounds (MLC) over nanoscale catalysts is important for improving the technologic processes occurring in the pyrolytic conversion of lignocellulose biomass into biofuels and value-added chemicals. Herein, we investigate catalytic pyrolysis of MLC (pyrocatechol (P), guaiacol (G), ferulic (FA), and vanillic acids (VA)) over nanoceria using FT-IR spectroscopy, temperature-programmed desorption mass spectrometry (TPD MS), and thermogravimetric analysis (DTG/DTA/TG). FT-IR spectroscopic studies indicate that the active groups of aromatic rings of P, G, VA, and FA as well as carboxylate groups of VA and FA are involved in the interaction with nanoceria surface. We explore the general transformation mechanisms of different surface complexes and identify their decomposition products. We demonstrate that decomposition of carboxylate acid complexes occurs by decarboxylation. When FA is used as a precursor, this reaction generates 4-vinylguaiacol. Complexes of VA and FA formed through both active groups of the aromatic ring and decompose on the CeO2 surface to generate hydroxybenzene. The formation of alkylated products accompanies catalytic pyrolysis of acids due to processes of transalkylation on the surface.

Aminated nanoporous activated carbon fibers: Adsorption materials for the recovery of Cu2+ and Cd2+ ions

In this article, we report on and compare the texture, thermal properties, and adsorption capacity of aminated nanoporous activated carbon fibers (NACFs), which were prepared using the bromination followed by the amination with ethylenediamine, diethylamine, monoethanolamine, and sulfolanylethylenediamine. FTIR ATR confirmed the grafting of the amino groups. Surface morphology and microstructure of NACFs were assessed based on the results of SEM and nitrogen adsorption. Simulation of nitrogen adsorption with 2D-NLDFT models showed a highly porous structure with nanopore diameters between 0.5 and 0.8 nm and from 1.1 to 2.1 nm. The aminated NACFs with up to 0.95 mmol of amino groups per gram have moderate thermal stability. Thermal decomposition and detachment of amino groups were registered by TPD MS and TGA between 200 °C and 400 °C. Effective adsorption of 80–98% of Cd2+ and Cu2+ ions from very dilute water solutions were achieved with the aminated NACFs. The equilibrium adsorption isotherms for Cd2+ and Cu2+ were well fitted with the Langmuir and Dubinin-Radushkevich (DR) models. These results suggest sufficient energy homogeneity of the carbon surfaces and adsorption in the nanopores. As compared with the unmodified NACFs, the adsorption of Cd2+ and Cu2+ ions on the aminated surface of the NACFs is characterized by up to three times higher values of the maximum adsorption capacity and from two to five times higher values of the constants describing the adsorption equilibrium for each model.

Interface tuning of Cu+/Cu0 by zirconia for dimethyl oxalate hydrogenation to ethylene glycol over Cu/SiO2 catalyst

An efficient ZrO2–doped Cu/SiO2 catalyst was fabricated through hydrolysis precipitation method (HP) and used to produce ethylene glycol (EG) through dimethyl oxalate (DMO) hydrogenation. The states for zirconia on copper catalyst and roles in DMO hydrogenation were investigated through various characterization tools, including N2 physical adsorption, XRD, H2–TPR, Methyl glycolate–TPD–MS, XPS, XAES as well. Compared with common ammonia evaporation and co–precipitation methods used in catalyst preparation, this HP method is found to effectively suppress the agglomeration and further size growth of copper nanoparticles by enhancing the interactions between copper and zirconia species. More importantly, uniform distribution of ZrO2 dopant is achieved due to the pseudo-homogeneous reactions in the mixing step of catalyst preparation. A proper amount of zirconium dopant helps achieve the desirable proportion of Cu+/(Cu++Cu0) for surface copper species, especially promotes the production of Cu+ species originated from Cu–ZrO2 species at the interface of copper and zirconia particles. In comparison with Cu+ species formed from copper phyllosilicates reduction, the Cu+ sites derived from Cu–ZrO2 species show higher adsorption ability of MG, an important intermediate species in ethylene glycol production. These adsorbed MG molecules further react with atomic hydrogen shifted from adjacent metallic copper surface, leading to a higher catalytic behavior. For the EG production via DMO hydrogenation, the turnover frequency (TOF) normalized by Cu0 species on CuZr/SiO2 catalyst is 1.8 times than that of traditional Cu/SiO2 counterpart. Due to the enhanced synergy effect between Cu+ and Cu0 active sites, a lower activation energy of ester hydrogenation on this ZrO2–doped Cu/SiO2 catalyst is believed to be responsible for the significant improvement.

Synthesis, spectral characterization and DFT calculations of novel Ag(I) π-coordination polymeric complexes based on N-allylmorpholine-4-carbothioamide

Two complexes of Ag(I) with the N-allylmorpholine-4-carbothioamide (HL) with general formula ([Ag(HL)NO3]·3H2O)n (1) and [Ag(HL)NO3]n (2) were synthesized and isolated in crystalline state. X-ray diffraction study of compounds showed that both complexes are coordination polymers which differ by coordination manners of nitrate anions and presence of cocrystallized water molecules. In solid state in both complexes the ligand molecules are coordinated in bridging mode by μ2-S atom and the CC double bond of the allyl moiety with formation of stable six-membered chelate metallocycles and 1D Ag–S–Ag polymeric chains. However dissolution of the complexes in DMSO leads to cleavage of polymeric chains as well as Ag-(CC) π-coordination bonds, as evidenced by the 1H and 13C NMR spectroscopy data. Crystallographic data have also revealed so-called “additional” coordination of Ag+ ions, which complements the “usual” coordination polyhedra of Ag+ expanding its coordination numbers from 3 to 5 and 6, leading to stabilization of such compounds in solid state. Results of DFT calculation of IR spectra were compared with experimental data and fragmentation of complexes was investigated by MALDI-TOF mass spectrometry and TPD MS methods.

Effect of SO2 treatment in the presence and absence of O2 over ceria–titania oxides for selective catalytic reduction

The performance of selective catalytic reduction of NO over ceria–titania (Ce–TiOx)-based materials after aging in SO2 atmosphere in the presence and absence of O2 was investigated, showing that O2 gave acceleration on the deactivation of the samples for the enhanced SO2 adsorption and sulfation over ceria-based materials. FT-IR and TPD–MS over samples with 10wt%, 50wt% and 90wt% of CeO2 were carried out. The results indicated the poisoning effect of SO2 over Ce–TiOx catalyst for SCR is in accordance with the amount of sulfite or sulfate over Ce–TiOx with a certain percentage of CeO2.

In Ukrainian

Search for the “structure-reactivity” correlations of the thermally stimulated reactions of cinnamic acids on the surface of catalysts is important for the development of pyrolytic conversion methods of lignocellulosic biomass components into products with high added value, in particular, into styrene. Therefore, in this work, the kinetics of pyrolysis of the reaction series of para-substituted derivatives of trans-cinnamic acid (Н, -СН 3 , -С(СН 3 ) 3 , -ОСН 3 , -F) on the surface of nanosized silica by the method of thermoprogrammed desorption mass spectrometry (TPD MS) was investigated. The products of pyrolytic reactions on the surface are identified ‒ the corresponding, para-substituted vinylbenzenes, phenylacetylenes, and phenylketenes. The kinetic parameters of the decarboxylation, ketenization, and decarbonylation reactions were calculated. The correlations "structure-reactivity" between the kinetic parameters (activation energy) and thermodynamic parameters (Hammett substituents constants) have been obtained, which indicate that electron-donor substituents reduce the activation energy of these three reactions while the electron-acceptor substituents increase it. That is, in the transitional state of the rate-limiting step, a decrease in the electron density is observed at the reaction center. The calculated values of the reaction constants ρ show that the studied reactions dependent on the sensitivity to the effect of the substituents are placed in a sequence: decarbonylation> decarboxylation> ketenization. The formation of phenylacetylenes is the most sensitive to structural changes in the molecule and proceeds through the most polar transition state.

Thermal Transformation of Caffeic Acid on the Nanoceria Surface Studied by Temperature Programmed Desorption Mass-Spectrometry, Thermogravimetric Analysis and FT–IR Spectroscopy

The studies of pyrolysis of caffeic acid (CA) and its surface complexes is important for the development of technologies of heterogeneous catalytic pyrolysis of plant- and wood- based renewable biomass components. In this work, the structure and thermal transformations of the surface complexes of CA on the surface of nanoceria were investigated using Fourier transform–infrared (FT–IR) spectroscopy, thermogravimetric analysis (TGA) and temperature-programmed desorption mass spectrometry (TPD MS). It was found that CA on the surface of cerium dioxide forms several types of complexes: bidentate carboxylates, monodentate carboxylates and complexes formed as a result of interaction with phenolic hydroxyl groups. This is due to the ability of nanosized cerium dioxide to generate basic hydroxyl groups that can deprotonate phenolic groups to form phenolates on the surface. The main pyrolysis products were identified. The possible ways of forming 3,4-dihydroxyphenylethylene, acetylene carboxylic acid, pyrocatechol and phenol from surface complexes of CA were suggested. It was established that on the nanoceria surface effectively occur the decarboxylation, decarbonylation, and dehydration reactions of the CA, which are the desirable processes in biomass conversion technologies.