Volatile Oxidation Research Articles

Revealing the effect of Al content on the oxidation of γ'-strengthened cobalt-based superalloys

The effect of Al content (6–9 at%) on the oxidation of multicomponent γ'-strengthened cobalt-based superalloys at 800 ℃–1000 ℃ was revealed by combining experimental and CALPHAD approaches. The results showed that increasing Al content can improve the oxidation resistance of the alloys by promoting the formation of a dense Al2O3 layer and reducing the activity of Ti at 800 ℃ and 900 ℃. However, at 1000 ℃, increasing Al content can promote the formation of Co(W,Mo)O4 and TaTiO4, as well as oxide volatilization, which aggravated the cracking and spallation of the oxide scales and deteriorated the oxidation resistance of the alloys.

Solar Carbo-Thermal and Methano-Thermal Reduction of MgO and ZnO for Metallic Powder and Syngas Production by Green Extractive Metallurgy

The solar carbo-thermal and methano-thermal reduction of both MgO and ZnO were performed in a flexible solar reactor operated at low pressure through both batch and continuous operations. The pyro-metallurgical process is an attractive sustainable pathway to convert and store concentrated solar energy into high-value metal commodities and fuels. Substituting fossil fuel combustion with solar energy when providing high-temperature process heat is a relevant option for green extractive metallurgy. In this study, a thermodynamic equilibrium analysis was first performed to compare the thermochemical reduction of MgO and ZnO with solid carbon or gaseous methane, and to determine the product distribution as a function of the operating conditions. The carbo-thermal and methano-thermal reduction of the MgO and ZnO volatile oxides was then experimentally assessed and compared using a directly irradiated cavity-type solar reactor under different operating conditions, varying the type of carbon-based reducing agent (either solid carbon or methane), temperature (in the range 765–1167 °C for ZnO and 991–1550 °C for MgO), total pressure (including both reduced 0.10–0.15 bar and atmospheric ~0.90 bar pressures), and processing mode (batch and continuous operations). The carbo-thermal and methano-thermal reduction reactions yielded gaseous metal species (Mg and Zn) which were recovered at the reactor outlet as fine and reactive metal powders. Reducing the total pressure favored the conversion of both MgO and ZnO and increased the yields of Mg and Zn. However, a decrease in the total pressure also promoted CO2 production because of a shortened gas residence time, especially in the case of ZnO reduction, whereas CO2 formation was negligible in the case of MgO reduction, whatever the conditions. Continuous reactant co-feeding (corresponding to the mixture of metal oxide and carbon or methane) was also performed during the solar reactor operation, revealing an increase in both gas production yields and reaction extent while increasing the reactant feeding rate. The type of carbon reducer influenced the reaction extent, since a higher conversion of both MgO and ZnO was reached when using carbon with a highly available specific surface area for the reactions. The continuous solar process yielded high-purity magnesium and zinc content in the solar-produced metallic powders, thus confirming the reliability, flexibility, and robustness of the solar reactor and demonstrating a promising solar metallurgical process for the clean conversion of both metal oxides and concentrated solar light to value-added chemicals.

The modeling and products prediction for biomass oxidative pyrolysis based on PSO-ANN method: An artificial intelligence algorithm approach

In this work, the oxidative pyrolysis of two kinds of biomass was conducted on a fixed bed reactor. The pyrolysis product yields (water, tar, gas and char) as well as two kinds of gaseous species (CO and CO2) were analyzed. Based on the experiments, the artificial neural network (ANN) model was built and trained for product yield prediction. Experimental results show that the reaction mechanism of oxidative pyrolysis was much complicated than inert pyrolysis. With the addition of oxygen, homogenous and heterogenous oxidation of volatiles or nascent char significantly influenced the product distribution. Modeling results showed that the combination transfer function of logsig and purelin for hidden layer was suitable for modeling of biomass oxidative pyrolysis. Individual ANN model had weak prediction performance for the data points located around the boundary of database. This weakness as well as the tendency of local convergence leaded to the decline of prediction accuracy for individual ANN model. Particle swarm optimization (PSO) was further used to optimize the initial weight and threshold value of the ANN model, which significantly increased the prediction accuracy. The relative error of the PSO-ANN model decreased to below 10%, which proved to be a effective tool for modeling of biomass oxidative pyrolysis.

Enhanced thermal resistance and ablation properties of ethylene-propylene-diene monomer rubber with boron-containing phenolic resins

With the development of aerospace industry, higher requirements have been put forward for the thermal properties of internal insulation materials for heat protection of solid rocket engine chamber. In this study, boron-containing phenolic resin (BPR) was chosen as the thermal-resistant filler of ethylene-propylene-diene monomer (EPDM). By adjusting the amount of BPR, a series of BPR/EPDM were prepared and their thermal, mechanical, and ablation properties were studied. The results showed that the addition of BPR significantly improved the char yield of EPDM. The char yield of BPR/EPDM was 21.6%, which increased by 17.9% (800 °C) relative to EPDM. By studying the structural evolution of BPR/EPDM during pyrolysis, boron oxide (B2O3) was formed, which avoided the formation of volatile carbon oxides and reduced the carbon loss. The molten B2O3 penetrated into the pores of carbonization products, which can protect the unstable edges of graphitic carbon and improve the ablation performance of BPR/EPDM. The linear ablation rate of BPR/EPDM was 0.045 mm/s (the lowest reported in current references). Additionally, the addition of BPR improved the graphitization degree of carbonization product. This research is expected to provide a resin matrix with excellent comprehensive performance and large-scale production for combustion chamber of the solid engine.

The Role of Silica in the Chlorination–Volatilization of Cobalt Oxide by Using Calcium Chloride

The role of silica in the chlorination–volatilization of cobalt oxide, using calcium chloride, is investigated in this paper. It is found that the Co volatilization percentage of the CoO–Fe2O3–CaCl2 system is not larger than 12.1%. Silica plays an important role in the chlorination–volatilization of cobalt oxide by using calcium chloride. In the CoO–SiO2–Fe2O3–CaCl2 system, the Co volatilization percentage is initially positively related to the molar ratio of SiO2 to CaCl2, and remains almost constant when the molar ratio of SiO2 to CaCl2 rises from zero to eight. The critical molar ratios of SiO2 to CaCl2 are 1 and 2 when the molar ratios of CaCl2 to CoO are 8.3 and 16.6, respectively. The Co volatilization percentage remains almost constant with the increase in CaO concentration, and decreases when Al2O3 and MgO are added. Ca2SiO3Cl2 is determined after roasting at 1073 K and 1173 K, and disappears at temperatures in excess of 1273 K in the calcines from the CoO–SiO2–CaCl2 system. CaSiO3 always exists in the calcines at temperatures in excess of 973 K.

The effect of refining process on the volatile compounds, oxidation stability and fatty acids profile of soybean oil using an electrostatic field

The effect of refining process on the volatile compounds, oxidation stability and fatty acids profile of soybean oil using an electrostatic field

Physical and Oxidative Stability of Low-Fat Fish Oil-in-Water Emulsions Stabilized with Black Soldier Fly (Hermetia illucens) Larvae Protein Concentrate.

The physical and oxidative stability of fish oil-in-water (O/W) emulsions were investigated using black soldier fly larvae (BSFL) (Hermetia illucens) protein concentrate as an emulsifier. To improve the protein extraction and the techno-functionality, defatted BSFL powder was treated with ohmic heating (BSFL-OH) and a combination of ohmic heating and ultrasound (BSFL-UOH). Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) were performed in order to characterize the secondary structure and thermal stability of all protein concentrate samples. The interfacial properties were evaluated by the pendant drop technique. The lowest interfacial tension (12.95 mN/m) after 30 min was observed for BSFL-OH. Dynamic light scattering, ζ-potential and turbiscan stability index (TSI) were used to evaluate the physical stability of emulsions. BSFL-OH showed the smallest droplet size (0.68 μm) and the best emulsion stability (TSI = 8.89). The formation of primary and secondary volatile oxidation products and consumption of tocopherols were evaluated for all emulsions, revealing that OH and ultrasound treatment did not improve oxidative stability compared to the emulsion with untreated BSFL. The results revealed the promising application of BSFL proteins as emulsifiers and the ability of ohmic heating to improve the emulsifying properties of BSFL proteins.

Influence of water leaching on alkali-induced slagging properties of biomass straw

Deposition or slagging problem caused by the alkali metal species is one of the major obstacles to utilize biomass fuel in combustion and gasification plant. The paper mainly studies the effect of water leaching on alkali-induced slagging properties of corn straw and rice straw. The original mineral form of alkali elements in biomass straw was studied with comparison of low temperature ash of biomass before and after water leaching. The release and transformation of alkali compounds in biomass straw at different temperatures during heating were analyzed with combination of the XRD result of the heated biomass and the chemical composition of the digested samples. The result shows that the potassium in corn and rice straw mainly exists in the form of KNO3, KClO4, K2SO4 and KAlSi3O8, in which KNO3, K2SO4 and KClO4 is mostly removed in water leaching. The fusion temperatures increased after water leaching, especially for rice straw ash, which is a typical sample that the basic compounds are mainly potassium-containing compounds. The decrease of potassium content with temperature in the original corn and rice was because the potassium-containing minerals decomposed and escaped at 25−1000°C. The release of potassium in the range of 400−800°C significantly reduced for corn and rice straw after water leaching, but the potassium content will still decrease above 800°C. The decrease of magnesium content in corn with increasing temperature may be due to the volatilization of magnesium oxide under the action of carbon reduction. For fuels with high alkali metal content after water leaching, the residual alkali metal will still escape and cause deposition or slagging in the furnace, especially in the temperature range above 800°C.

Determination of oxidation rates and volatile oxidation products for HTGR graphite matrix material exposed to steam atmospheres

High-temperature gas-cooled reactors (HTGRs) in operation use tristructural isotropic (TRISO) particles embedded in graphite and carbonized resin matrix to form the fuel element. This graphite matrix material serves as a supportive structural element, heat transfer medium, and neutron moderator. In HTGR designs, fuel compacts are exposed to helium coolant, which facilitates high outlet temperatures (750°C<T<950°C) and subsequently greater thermal efficiency than current commercial power reactors. However, data pertaining to the oxidation resistance of graphite matrix material in HTGR accident or off-normal conditions (<50k kPa pH2O, 800°C<T<1600°C) is limited. In this study, both the oxidation behavior of matrix graphite material and its gas-phase products, including CO, CO2, and H2, are quantified in varied oxidant atmospheres using a coupled thermogravimetric analyzer and mass spectrometer. Oxidation rates reported here for varied steam (H2O [g]) atmospheres are predominantly linear and comparable with literature values in the range of tested temperatures (800–1200°C). Changes in dominant matrix oxidation products from primarily CO to a mixture of CO, CO2, and H2 were observed at higher temperatures (≥1000°C) and steam atmospheres (≥5 kPa pH2O). Kinetic data indicates that there was no shift in oxidation regime with chemical oxidation occurring at all temperatures and H2O (g) atmospheres tested. These data provide insight into the oxidation behavior of graphite matrix material and will inform future testing conditions, notably mixed atmospheric conditions, of HTGR fuel elements.

Nanoencapsulation-Based Edible Coating of Essential Oils as a Novel Green Strategy Against Fungal Spoilage, Mycotoxin Contamination, and Quality Deterioration of Stored Fruits: An Overview.

Currently, applications of essential oils for protection of postharvest fruits against fungal infestation and mycotoxin contamination are of immense interest and research hot spot in view of their natural origin and possibly being an alternative to hazardous synthetic preservatives. However, the practical applications of essential oils in broad-scale industrial sectors have some limitations due to their volatility, less solubility, hydrophobic nature, and easy oxidation in environmental conditions. Implementation of nanotechnology for efficient incorporation of essential oils into polymeric matrices is an emerging and novel strategy to extend its applicability by controlled release and to overcome its major limitations. Moreover, different nano-engineered structures (nanoemulsion, suspension, colloidal dispersion, and nanoparticles) developed by applying a variety of nanoencapsulation processes improved essential oil efficacy along with targeted delivery, maintaining the characteristics of food ingredients. Nanoemulsion-based edible coating of essential oils in fruits poses an innovative green alternative against fungal infestation and mycotoxin contamination. Encapsulation-based coating of essential oils also improves antifungal, antimycotoxigenic, and antioxidant properties, a prerequisite for long-term enhancement of fruit shelf life. Furthermore, emulsion-based coating of essential oil is also efficient in the protection of physicochemical characteristics, viz., firmness, titrable acidity, pH, weight loss, respiration rate, and total phenolic contents, along with maintenance of organoleptic attributes and nutritional qualities of stored fruits. Based on this scenario, the present article deals with the advancement in nanoencapsulation-based edible coating of essential oil with efficient utilization as a novel safe green preservative and develops a green insight into sustainable protection of fruits against fungal- and mycotoxin-mediated quality deterioration.

Plasma-wall interaction studies in W7-X: main results from the recent divertor operations

Wendelstein 7-X (W7-X) is an optimized stellarator with a 3-dimensional five-fold modular geometry. The plasma-wall-interaction (PWI) investigations in the complex 3D geometry of W7-X were carried out by in situ spectroscopic observations, exhaust gas analysis and post-mortem measurements on a large number of plasma-facing components extracted after campaigns. The investigations showed that the divertor strike line areas on the divertor targets appeared to be the major source of carbon impurities. After multistep erosion and deposition events, carbon was found to be deposited largely at the first wall components, with thick deposits of >1 μm on some baffle tiles, moderate deposits on toroidal closure tiles and thin deposits at the heat shield tiles and the outer wall panels. Some amount of the eroded carbon was pumped out via the vacuum pumps as volatile hydrocarbons and carbon oxides (CO, CO2) formed due to the chemical processes. Boron was introduced by three boronizations and one boron powder injection experiment. Thin boron-dominated layers were found on the inner heat shield and the outer wall panels, some boron was also found at the test divertor unit and in redeposited layers together with carbon. Local erosion/deposition and global migration processes were studied using field-line transport simulations, analytical estimations, 3D-WallDYN and ERO2.0 modeling in standard magnetic field configuration.

Analysis of functionality distribution and microstructural characteristics of upgraded rice husk after undergoing non-oxidative and oxidative torrefaction

Rice husk, a typical agricultural by-product was used for experimental investigation on characterizing the variations in fuel behaviors before and after torrefaction performed under different conditions. The effects of torrefaction temperature (493, 543 and 573 K), atmosphere (argon, air and flue gas) and duration (30 and 60 min) on the compositional variation, microstructural evolution, functional group distribution and surface hydrophobicity were evaluated systemically through the utilization of elemental analysis, FTIR, Raman spectra, XPS and contact angle. Oxidative torrefaction expressed a tendency to improve the torrefaction efficiency and increase the carbon content in torrefied sample due to the simultaneous occurrence of volatile release, carbonization and surface oxidation. Oxidizing agents could accelerate the decomposition or conversion of surface hydrophilic groups during oxidative torrefaction process effectively, strengthening the hydrophobicity of torrefied sample significantly. Furthermore, partial oxidation and thermal degradation tended to promote the crack of condense aromatic structures synergistically, increasing the proportion of active structures in the torrefied rice husk. Simultaneously, some nitrogen atoms initially located inside the aromatic structures with high thermal stability would migrate to the edge rapidly during the oxidative torrefaction (N-Q → N-5 + N-6). In the process of air torrefaction, excessive oxidants would reduce the content of reactive structure and functional group with low thermal stability through severe oxidation reaction, reducing the quality of torrefied sample, especially at high temperatures. The results in this study illustrated that torrefaction performed in flue gas atmosphere at 573 K for 30 min was the optimum torrefaction condition for rice husk upgradation, and employing flue gas as the carrier gas for biomass torrefaction was more effective and economical than N2 and air in improving the fuel quality of rice husk.

A Review and Experimental Revisit of Alternative Catalysts for Selective Oxidation of Methanol to Formaldehyde

The selective oxidation of methanol to formaldehyde is a growing million-dollar industry, and has been commercial for close to a century. The Formox process, which is the largest production process today, utilizes an iron molybdate catalyst, which is highly selective, but has a short lifetime of 6 months due to volatilization of the active molybdenum oxide. Improvements of the process’s lifetime is, thus, desirable. This paper provides an overview of the efforts reported in the scientific literature to find alternative catalysts for the Formox process and critically assess these alternatives for their industrial potential. The catalysts can be grouped into three main categories: Mo containing, V containing, and those not containing Mo or V. Furthermore, selected interesting catalysts were synthesized, tested for their performance in the title reaction, and the results critically compared with previously published results. Lastly, an outlook on the progress for finding new catalytic materials is provided as well as suggestions for the future focus of Formox catalyst research.

Assessment of long-term energy and environmental impacts of the cleaner technologies for brick production

Brick kiln sector in South Asia contributes to nearly quarter of the global bricks production. Coal is the primary fuel used by this industry and its inefficient combustion process results in harmful pollutants contributing to deteriorating air quality, health problems in local communities, and greenhouse gas emissions. The aim of this study is to investigate the impact of cleaner technologies and adoption pathways to achieve environment-friendly and energy-efficient production of bricks in Pakistan during 2019–2050. The study incorporates various timelines for (Zig-Zag Kilns) ZZKs and Vertical Shaft Brick Kilns (VSBKs) adoption, and the phasing out of conventional, Fixed Chimney Bull’s Trench Kiln (FCBTKs). Low Emissions Analysis Platform (LEAP) based numerical calculations are performed to simulate brick production from 2019–2050 for seven different scenarios incorporating an assimilated technology mix of FCBTKs, ZZKs, and VSBKs. Emissions of carbon dioxide, carbon monoxide, black carbon, methane, non-methane volatile organic compounds, particulate matter, sulfur oxides and nitrogen oxides are considered in this study. The swiftness of energy demand, and emissions reductions are greatly impacted by the elimination of the conventional FCBTKs. By adopting clearner brick manufacturing, 365.5 million tons (21.8%) of GHG emissions reduction can be achieved. The annual social cost of using FCBTKs increases from 1.02 billion $ in 2019 to 1.88 billion $ in 2050. Cumulative fuel saving potential of retrofitting to ZZKs is 157 million tons (17.7%) and it offers nearly 0.92 billion $ (51%) savings in annual social cost for year 2050. Our study finds that early adoption of ZZKs would benefit more than delayed adoption of VSBKs. However, transition to ZZK/ VSBK alone would not be sufficient to achieve net-zero carbon emissions. Carbon neutral fuels such as biomass and refuse-derived fuel (RDF) appear as an attractive option for deep decarbonization of this sector.

Comparative study of accelerated assays for determination of equivalent days in the shelf life of roasted high oleic peanuts: Chemical and volatile oxidation indicators in accelerated and room temperature conditions

Lipids present in peanuts are susceptible to oxidation, which affects food quality and safety, for this reason shelf-life studies are carried out. The objective was to determine the relation between accelerated oxidation conditions and room temperature storage for roasted peanuts. Lipid oxidation indicators and roasted flavour volatiles were measured. There was a negative correlation between roasted and oxidation volatiles. In this research, 2,5-dimethylpyrazine and 2-ethyl-3,6-dimethylpyrazine were good indicators of the storage conditions of roasted peanuts, and the peroxide value (PV) was the most important oxidation indicator. For the comparision of equivalent days, it was used the peroxide value which reached 7.90, 2.47 and 0.89 Meq.O2/kg after 21 days at 25, 45 and 60 °C, respectively. The accelerated storage condition of 60 °C is optimal for estimation of the shelf life at 25 °C wherein 1 day at 60 °C is equal to 8.79 days at 25 °C.

Poorly conductive biochar boosting extracellular electron transfer for efficient volatile fatty acids oxidation via redox-mediated mechanism

This study explored the performances, and associated mechanisms of biochar promoting volatile fatty acids (VFA) oxidation via extracellular electron transfer (EET) pathway. It was found that in a bioelectrochemical system, adding biochar suspension remarkably enhanced electricity generation whatever acetate or propionate used as an electron donor. The maximum current density in biochar-assisted groups reached 1.6–2.2 A/m2, which were 69.2–220.0% higher than that of control groups. The lower electrical resistance of anode in biochar-assisted groups was potentially attributed to the formed biofilm dominated by electro-active Geobacteraceae, and the electron donor type depending on dominant genus. In specific, with biochar assistance, Desulfuromonas enriched from 1.1% to 25.0% when acetate as an electron donor, and the relative abundance of Geobacter increased from 4.6% to 31.7% as dominant genus in propionate-added group. Electrochemical analysis uncovered that biochar hardly elevated sludge electrical conductivity, while the excellent redox-based electron exchange transfer capacity likely made biochar as a transient electron acceptor, which was more accessible than anode to support the metabolism of electroactive bacteria in the initial stage. Meanwhile, the porous surface area of biochar particle likely provided a “bridge” between suspended sludge and anode, to support a more directional evolution of electroactive bacteria on anode. This dual-function of biochar achieved a sustainable VFA oxidation via EET-based pathway.

Mass Loss of Platinum-Rhodium Thermocouple Wires at 1324°C

It is known that platinum-rhodium thermocouples exhibit mass loss when in the presence of oxygen at high temperatures due to the formation of volatile oxides of platinum and rhodium. The mass losses of platinum, Pt-6%Rh and Pt-30%Rh wires, commonly used for thermocouples, were considered in this paper to characterise the mass loss of wires of the three compositions due to formation and evaporation of the oxides PtO2 and RhO2 under the conditions that would be seen by thermocouples used at high temperature. For the tests, the wires were placed in thin alumina tubes to emulate the thermocouple format, and the measurements were performed in air at a temperature of 1324°C, i.e. with oxygen partial pressure of 21.3 kPa. It was found that the mass loss of the three wires increases linearly with elapsed time, consistent with other investigations, up to an elapsed time of about 150 h, but after that, a marked acceleration of the mass loss is observed. Remarkably, previous high precision studies have shown that a crossover after about 150 h at 1324°C is also observed in the thermoelectric drift of a wide range of platinum-rhodium thermocouples, and the current results are compared with those studies. The mass loss was greatest for Pt-30%Rh, followed by Pt6%Rh, then platinum.

Cellulose gasification with Ca–Fe oxygen carrier in chemical-looping process

Biomass-derived chemical looping gasification (BCLG) is a novel technology for lignocellulose energy applications. Ca–Fe oxygen carriers have been proven to be a potential material for efficient lignocellulose conversion and hydrogen-enriched syngas production in process studies. In this study, Thermogravimetry-mass spectrometry (TG-MS), pyrolysis chromatography-mass spectrometry (Py-GC-MS) and fixed-bed experiments were conducted, and the cellulose BCLG product was analyzed to explore the mechanism of reaction between Ca–Fe OCs and biomass char or volatiles. The mechanism of the synergistic effect of Ca–Fe was analyzed to explain the characteristics of the OCs. The results suggest the Ca-based materials act as catalysts to promote the decomposition of cellulose monomers at primary reaction and char at secondary reaction, and also promote the reforming and oxidation of volatiles by chemisorption. Ca participates in the construction of inert substances, such as Ca2Fe2O5, to avoid the deep oxidation of CO and H2. Fe-based material supplies oxygen and promotes the reforming of volatile. Compared with Fe2O3 and CaO/Fe2O3, CaFe2O4 shows a better performance on carbon conversion and H2 production below 850 °C.

Preparation and properties of porous Al5BO9 for high‐temperature wave‐transparent and thermal insulating applications

AbstractPorous Al5BO9 is a promising high‐temperature wave‐transparent material. However, method for the preparation of this material is not readily available. Herein, porous Al5BO9 ceramics with controlled porosity and small volume shrinkage are successfully prepared by using Al2O3 and B2O3 as starting materials without pore formers. The SEM and pore size distribution studies show that the as‐prepared porous Al5BO9 ceramics exhibit a uniform pore structure and a narrow pore size distribution. Intriguingly, simply adjusting the densities of the green bodies, the density and porosity of the porous Al5BO9 ceramics can be controlled. The pore‐forming mechanism is presumed to be a combination of boron oxide volatilization during the high‐temperature synthesis and lap of elongated grains. Porous Al5BO9 ceramics have good high‐temperature stability, which can maintain dimensional and composition stability up to 1673 K. The compressive strength can reach 211 MPa at 32.4% porosity and the dielectric constant can be as low as 3.02 at 43.2% porosity. In addition, the dielectric constant and loss tangent keep almost unchanged with temperature.

Screening of the Honey Aroma as a Potential Essence for the Aromachology

The aim of the study was to determine the aroma profiles of four kinds of Slovak honey (sunflower, honeydew, acacia, and linden) by a qualitative and quantitative screening of their volatile compounds and by gas chromatography for the potential use in the aromachology and the business sphere. The results showed that several unique volatiles were identified in one kind of honey, while they were not identified in the remaining ones. The acacia honey had the unique volatile linalool oxide (1.13–3.9%); linden honey had the unique volatiles nerol oxide (0.6–1.6%), ethyl esters (0.41–8.78%), lilac aldehyde D (6.6%), and acetophenone (0.37%). The honeydew honey had the unique volatiles santene (0.28%) and cyclofenchene (0.59–1.39%), whereas 2-bornene (0.43–0.81%) was typical for sunflower honey. While linden honey was characterized by fruity ethyl esters, honeydew honey had more monoterpenoid compounds. In the principal component analysis model, the four kinds of honey could not be differentiated by aroma volatiles. However, it was possible to classify the linden and sunflower honey using the LDA. In conclusion, the current study provided experimental evidence that the marker compounds from different kinds of honey might be promising candidates for production of inhaling aromas.