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Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We studied the C–H activation of ethane on the palladium (Pd) atomic clusters at the CCSD(T)/TZ//B3LYP/DZ level of theory, where TZ and DZ denote the LANL2 valence triple-ζ and double-ζ basis sets that include a relativistic pseudopotential for the Pd core electrons. In this study, we globally optimized first the Pdn clusters (n = 1–8) and then the transition state (TS) structures of Pdn + C2H6 → H−Pdn−C2H5. For each cluster size, we studied four spin states (S = 0, 1, 2, 3). The Pd atom is in the singlet electronic state ([Kr]4d10) at the CCSD(T) level. The CCSD(T) global minima of the Pd3, Pd7, and Pd8 clusters are also in the singlet electronic state, whereas the CCSD(T) global minima of Pd2, Pd4, Pd5, and Pd6 are in the triplet electronic state. The atomization energy of Pdn increases monotonically with the cluster size. Pd4 and Pd6 are particularly stable relative to their neighboring sizes. Among all sizes, Pd4 is the least active toward the C–H bonds in ethane, followed by sizes 5, 7, 3, and 1, whereas Pd2, Pd6, and Pd8 are the most active: the enthalpy of activation of the Pdn + C2H6 → H−Pdn−C2H5 reaction at room temperature are –29, –21, and 8 kJ/mol at these three sizes, respectively, indicating their strong ability to activate ethane. Among these three sizes, Pd2 is highly unstable and thus less ideal. Pd6 and Pd8 are both energetically stable and active toward the C–H bonds of ethane. [ABSTRACT FROM AUTHOR]

The existing fundamental similarities in the chemistry of structurally related carbon and silicon compounds have been demonstrated. Stable silicon analogs of ethylene, silenes or silaethylenes R2C=SiR2 and disilenes R2Si=SiR2, as well as ethyne (acetylene) analogs, disilynes RSi≡SiR, have been considered. A number of unique branched (bulky) organic and organosilicon substituents have been described; the introduction of such substituents to double- or triple-bonded silicon atoms makes it possible to protect the latter from the action of atmospheric oxygen and moisture and prevent secondary dimerization (oligomerization) processes. Examples are given of steric protection for obtaining kinetically stable unsaturated silicon compounds which were characterized by IR, NMR, and UV-Vis spectroscopy and X-ray analysis. [ABSTRACT FROM AUTHOR]

Co/TiO2 catalysts with different cobalt loadings (3.8, 7.5 and 15 wt%) were prepared by impregnation method of Co(NO3)2 6H2O over titania. Samples containing Co(NO3)2·6H2O and TiO2 in stoichiometric proportions in order to obtain CoTiO3 and Co2 TiO4 phases were also synthesized. The effect of the calcination treatment at two different temperatures, 550 and 1150 °C, was investigated. Characterizations by several techniques, such as XRD, UV–vis–NIR, DRS, Raman and XPS, were carried out. XRD showed the coexistence of three phases: CoTiO3; Co2TiO4 and Co3O4 after calcination at 550 °C, while calcination at high temperature (1150 °C) led to single-phase systems (CoTiO3 or Co2TiO4). Diffuse reflection and XPS spectroscopy showed that divalent cobalt occupies octahedral sites in the ilmenite phase, and both tetrahedral and octahedral sites in the spinel phase. The catalytic performances of the prepared catalysts were evaluated in the oxidative dehydrogenation reaction (ODH) of ethane to ethylene, as a function of the Co content for Co/TiO2 catalysts and as a function of the calcination temperatures for the CoTiO3 and Co2TiO4 phases. Co(7.5)/TiO2 was the most active, although the conversion of ethane decreased in the first 150 min of the reaction, reaching values comparable to those of Co2TiO4 and CoTiO3; however, Co(7.5)/TiO2 was confirmed as having the best selectivity to ethylene in comparison with the bulk phases, CoTiO3 and Co2TiO4. The influence of the reaction mixture composition, specifically the presence of water, at different percentages, was investigated. There is a decrease in the overall ethane conversion and an increase in the ethylene selectivity when the percentage of water increases. This behavior can likely be attributed to an increase in the surface concentration of hydroxyl species (OH), resulting in heightened surface acidity. [ABSTRACT FROM AUTHOR]

To realize a super-leanburn SI engine with a very-high compression ratio, it is required to design a new fuel which could have low ignitability at a low temperature for antiknocking, but high ignitability at a high temperature for stable combustion. Ethane shows a long ignition delay time at a low temperature close to that of methane, but a short ignition delay time at a high temperature close to that of gasoline, as well as having a higher laminar burning velocity than those of methane and gasoline. In the present study, the antiknocking effect of adding methane with the RON of 120 or ethane with the RON of 108 to a regular gasoline surrogate fuel with the RON of 90.8 has been investigated. Adding methane or ethane by 35 % or 25 % in heat fraction, respectively, shows the same knock limit SI timing as that of a premium gasoline surrogate fuel with the RON of 100.2. In the relationship between the heat fraction of the gaseous fuel and the advance of knock limit CA50, the effect of adding ethane is 1.9 times larger than that of adding methane. The effect of adding the gaseous fuel is dependent not on the RON of the gaseous fuel, but on the OH consuming rate of the gaseous fuel. The effect of adding methane or ethane to the premium gasoline surrogate fuel has been also investigated. The effect of adding ethane is 1.7 times larger than that of adding methane. The effect of adding the gaseous fuel is not dependent on whether the liquid fuel has cool-flame reactions or not. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Engineering (China) / Huaxue Gongcheng is the property of Hualu Engineering Science & Technology Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report herein the preparation, characterization, and catalytic performance of a series of heterogeneous catalysts featuring highly dispersed zinc sites on zeolitic SSZ-13 and ZSM-5 frameworks. The materials are evaluated in the CO2-assisted oxidative ethane dehydrogenation, a very important reaction for the synthesis of platform chemicals. In particular, we find that Zn2.92/SSZ-13 exhibits high reactivity in the conversion of C2H6 and CO2 and high ethene selectivity. In line with the experimental results, we show that the selective character of the catalyst is due to the characteristic compositional structure of the support and its topology that can effectively confine CO2 molecules. An in-depth molecular analysis via operando studies and DFT calculations shows that the rate-limiting step of the reaction with CO2 is the second C-H bond dissociation to give C2H4. The addition of CO2 effectively reduces the energy barrier of this step, favoring desorption of C2H4 while limiting byproduct formation. Overall, this work demonstrates the breakthrough potential of catalysts made of highly dispersed zinc species on zeolites in relevant transformations.

Hydrogen is not only an important industrial chemical but also an energy carrier with increasing demand. However, the current production techniques are based on technologies that result in massive CO2 emissions. In contrast, the pyrolysis of alkanes in a liquid metal bubble column reactor does not lead to direct CO2 emissions. In order to transfer this technology from lab-scale to industrial applications, it has to be scaled up and the influences of the most common constituent of natural gas on the pyrolysis process have to be determined. For this study, the liquid metal bubble column technology developed at the KIT was scaled up by a factor of 3.75, referred to as the reactor volume. In this article, the experimental setup containing the reactor is described in detail. In addition, new methods for the evaluation of experimental data will be presented. The reactor, as well as the experimental results from pure methane pyrolysis (PM), will be compared to the previous generation of reactors in terms of methane conversion. It could be proven that scaling up the reactor volume did not result in a decrease in methane conversion. For part II of this publication, methane-ethane (MEM) gas mixtures and high calorific natural gas (nGH) were pyrolyzed, and the results were discussed on the basis of the present part I.

In aquifers, acetylene (C2H2) is a product of abiotic degradation of trichloroethene (TCE) catalyzed by in situ minerals. C2H2 can, in turn, inhibit multiple microbial processes including TCE dechlorination and metabolisms that commonly support dechlorination, in addition to supporting the growth of acetylenotrophic microorganisms. Previously, C2H2 was shown to support TCE reductive dechlorination in synthetic, laboratory-constructed cocultures containing the acetylenotroph Pelobacter sp. strain SFB93 and Dehalococcoides mccartyi strain 195 or strain BAV1. In this study, we demonstrate TCE and perchloroethene (PCE) reductive dechlorination by a microbial community enriched from contaminated groundwater and amended with C2H2 as the sole electron donor and organic carbon source. The metagenome of the stable, enriched community was analyzed to elucidate putative community functions. A novel anaerobic acetylenotroph in the phylum Actinobacteria was identified using metagenomic analysis. These results demonstrate that the coupling of acetylenotrophy and reductive dechlorination can occur in the environment with native bacteria and broaden our understanding of biotransformation at contaminated sites containing both TCE and C2H2IMPORTANCE Understanding the complex metabolisms of microbial communities in contaminated groundwaters is a challenge. PCE and TCE are among the most common groundwater contaminants in the United States that, when exposed to certain minerals, exhibit a unique abiotic degradation pathway in which C2H2 is a product. C2H2 can act as both an inhibitor of TCE dechlorination and of supporting metabolisms and an energy source for acetylenotrophic bacteria. Here, we combine laboratory microcosm studies with computational approaches to enrich and characterize an environmental microbial community that couples two uncommon metabolisms, demonstrating unique metabolic interactions only yet reported in synthetic, laboratory-constructed settings. Using this comprehensive approach, we have identified the first reported anaerobic acetylenotroph in the phylum Actinobacteria, demonstrating the yet-undescribed diversity of this metabolism that is widely considered to be uncommon.

Combining multiple secondary oil recovery (SOR)/enhanced oil recovery (EOR) methods can be an effective way to maximize oil recovery from heavy oil reservoirs; however, previous studies typically focus on single methods. In order to optimize the combined process of ethane-based cyclic solvent injection (CSI) and water/nanoparticle-solution flooding, a comprehensive understanding of the impact of injection pressure, water, and nanoparticles on CSI performance is crucial. This study aims to provide such understanding through experimental evaluation, advancing the knowledge of EOR methods for heavy oil recovery. Three approaches (an ethane-based CSI process, water flooding, and nanoparticle-solution flooding) were applied through a cylindrical sandpack model with a length of 95.0 cm and a diameter of 3.8 cm. Test 1 conducted an ethane-based CSI process only. Test 2 conducted a combination approach of CSI–water flooding–CSI–nanoparticle-solution flooding–CSI. Specifically, the injection pressure of the first CSI phase in Test 2 was gradually increased from 3500 to 5500 kPa. The second and the third CSI phases had the same injection pressure as Test 1 at 5500 kPa. The CSI process ceased once the oil recovery was less than 0.5% of the original oil in place (OOIP) in a single cycle. Results show that the ethane-based CSI process is sensitive to injection pressure. A high injection pressure is crucial for optimal oil recovery. The first CSI phase in Test 2, where the injection pressure was increased gradually, resulted in a 2.9% lower oil recovery and five times as much ethane consumption compared to Test 1, which applied a high injection pressure. It was also found that water flooding improved the oil recovery in the CSI process. In Test 2, the oil recovery factor of the second CSI phase increased by 57% after the water flooding process, which is likely due to the formation of water channels and a dispersed oil phase that increased the contact area between ethane and oil. Although the nanoparticle-solution flooding only had 0.3% oil recovery, after that the third CSI phase stimulated another 10.8% of OOIP even when the water saturation achieved more than 65%. This demonstrated that the addition of nanoparticles can maintain the stability of the foam and enhance the transfer of ethane to the heavy oil. Finally, Test 2 reached a total oil recovery factor of 76.1% on a lab scale, an increase of 45% compared to the single EOR method, which proved the combination process is an efficient method to develop a heavy oil field.

Thanks to investments in diversifying the supply of natural gas, Poland did not encounter any gas supply issues in 2022 when gas imports from Russia were ceased due to the Russian Federation’s armed intervention in Ukraine. Over the past few years, the supply of gas from routes other than the eastern route has substantially grown, particularly the supplies of liquefied natural gas (LNG) via the LNG terminal in Świnoujście. The growing proportion of LNG in Poland’s gas supply leads to a rise in ethane levels in natural gas, as verified by the review of data taken at a specific location within the gas system over the years 2015, 2020, and 2022. Using measurements of natural gas composition, the effectiveness of the steam hydrocarbon reforming process was simulated in the Gibbs reactor via Aspen HYSYS. The simulations confirmed that as the concentration of ethane in the natural gas increased, the amount of hydrogen produced, and the heat required for reactions in the reformer also increased. This article aims to analyze the influence of the changes in natural gas quality in the Polish transmission network caused by changes in supply structures on the mass and heat balance of the theoretical steam reforming reactor. Nowadays, the chemical composition of natural gas may be significantly different from that assumed years ago at the plant’s design stage. The consequence of such a situation may be difficulties in operating, especially when controlling the quantity of incoming natural gas to the reactor based on volumetric flow without considering changes in chemical composition.

Equilibrium molecular dynamics (EMD) simulations are used to model density ρL, dynamic viscosity ηL, and self-diffusivity Dself of liquid ethane at pressures close to saturation conditions and temperatures T between (184–298) K, close to the critical temperature Tc. To correct for a T-dependent drift of the simulated results from experimental data, a T-dependent force field modification from our previous studies is extended to a wider T-range. The modification is validated within this work by comparing predicted ρL, ηL, and Dself to experimental reference data. With the modification applied, EMD simulations are able to predict ρL, ηL, and Dself of liquid ethane at T = 298 K with relative deviations of 6.3%, 13%, and 28% from literature references, respectively. Simulations of binary mixtures of liquid ethane with different dissolved gases were performed to predict the Fick diffusivity D11. At a mole fraction of dissolved nitrogen xN2 = 0.03, a deviation of more than a factor of three is found between simulation results and experimental results determined using the dynamic light scattering method. This shows that EMD simulations are not able to predict the critical slowing down of D11 approaching Tc, despite excellent agreement between simulations and reference data for neat ethane. [ABSTRACT FROM AUTHOR]

The oxidative dehydrogenation of ethane to ethylene (ODHE) by Pt-based catalysts is a complex reaction involving endothermic dehydrogenation reactions occurring in gas and exothermic oxidation reactions occurring on the catalyst surface. It is a challenge to figure out its reaction mechanism. Kinetic Monte Carlo (kMC) method was employed to analyze 82 possible elementary reactions on Pt/Al 2 O 3. The path of CH 3 -CH 3 * →CH 3 -CH 2 * →CH 3 -CH* →C 2 H 4 * on the catalyst surface and the cracking of ethane in the gas phase were the main pathways for ethylene formation, which both needed heat supply. The step of C* +O* →CO* was the main oxidation path providing heat, with C* from C-C bond breaking or dehydrogenation of CH x species. The result was used to establish a particle-resolved fixed-bed computational fluid dynamics (CFD) model. The autothermal equilibrium was achieved at an inlet temperature of 773 K, a flow rate of 2 m/s, and a molar ratio (C 2 H 6 :O 2) of 3:1. Besides, the oxidation reaction was enhanced by increasing the inlet molar ratio, which meant that the C* species increased. The inlet velocity strengthened the heat transfer and a higher inlet velocity resulted in a lower bed temperature. The multi-scale simulation results can provide a reference for the design of an ethylene industrial reactor. [Display omitted] • Multiscale modeling of ODHE processes catalyzed by Pt was developed. • The main formation pathways of ethylene and by-products were identified. • Reaction conditions at temperature, concentration, and flow fields were studied. • Autothermal operation conditions for fixed bed reactor were obtained. [ABSTRACT FROM AUTHOR]

A series of cobalt doped hexagonal mesoporous silica (Co-HMS) with the different hydrothermal time was prepared by direct hydrothermal method and applied for oxidative dehydrogenation (ODH) reaction of ethane with carbon dioxide. Structural and chemical properties of the catalysts were characterized by nitrogen adsorption, X-ray powder diffraction (XRD), transmission electron microscopy (TEM), electron dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and Raman and ultraviolet–visible (UV–vis) spectroscopy. These characterizations showed that cobalt not only entered the framework of Co-HMS catalysts but also was evenly dispersed in the bulk. The valence state and coordination mode of cobalt played an important role in the whole ODH reaction system of ethane with carbon dioxide. 1%Co-HMS (1 h) with dominant Co2+ had the highest conversion of ethane (26.0%). The formation of tetrahedral coordination Co2+(Td) is beneficial to the breaking of ethane hydrocarbon bond and the improvement of ethylene selectivity. 1%Co-HMS (1 h) with more Co2+(Td) performed the highest ethylene selectivity of 92.6%, which was stable during the 10 h reaction time. [ABSTRACT FROM AUTHOR]

A series of cobalt doped hexagonal mesoporous silica (Co-HMS) with the different hydrothermal time was prepared by direct hydrothermal method and applied for oxidative dehydrogenation (ODH) reaction of ethane with carbon dioxide. Structural and chemical properties of the catalysts were characterized by nitrogen adsorption, X-ray powder diffraction (XRD), transmission electron microscopy (TEM), electron dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and Raman and ultraviolet–visible (UV–vis) spectroscopy. These characterizations showed that cobalt not only entered the framework of Co-HMS catalysts but also was evenly dispersed in the bulk. The valence state and coordination mode of cobalt played an important role in the whole ODH reaction system of ethane with carbon dioxide. 1%Co-HMS (1 h) with dominant Co2+ had the highest conversion of ethane (26.0%). The formation of tetrahedral coordination Co2+(Td) is beneficial to the breaking of ethane hydrocarbon bond and the improvement of ethylene selectivity. 1%Co-HMS (1 h) with more Co2+(Td) performed the highest ethylene selectivity of 92.6%, which was stable during the 10 h reaction time. [ABSTRACT FROM AUTHOR]

Photo‐driven CH4 conversion to multi‐carbon products and H2 is attractive but challenging, and the development of efficient catalytic systems is critical. Herein, we construct a solar‐energy‐driven redox cycle for combining CH4 conversion and H2 production using iron ions. A photo‐driven iron‐induced reaction system was developed, which is efficient at selective coupling of CH4 as well as conversion of benzene and cyclohexane under mild conditions. For CH4 conversion, 94 % C2 selectivity and a C2H6 formation rate of 8.4 μmol h−1 is achieved. Mechanistic studies reveal that CH4 coupling is induced by hydroxyl radical, which is generated by photo‐driven intermolecular charge migration of an Fe3+ complex. The delicate coordination structure of the [Fe(H2O)5OH]2+ complex ensures selective C−H bond activation and C−C coupling of CH4. The produced Fe2+ can be used to reduce the potential for electrolytic H2 production, and then turns back into Fe3+, forming an energy‐saving and sustainable recyclable system. [ABSTRACT FROM AUTHOR]

The single atom catalysts (SACs) show unique catalytic performance in heterogeneous reactions owing to unsaturated coordination sites and high metal atom dispersion. Herein, a simple wet impregnation method was utilized to synthetize of Fe−Al2O3 catalysts. The Fourier transformation infrared spectroscopy (FTIR) revealed that abundant OH group attached to the support (Al2O3) surface facilitating formation of isolated Fe single atom. High resolution transmission electron microscope (HR‐TEM) and extended X‐ray absorption fine structure (EXAFS) confirmed the Fe single atom architecture. Fe−Al2O3 (4.5 wt %) performed enhanced stability and activity on ethane dehydrogenation reaction. [ABSTRACT FROM AUTHOR]

This contribution presents the results of continued investigations on the production of hydrogen by means of pyrolysis in a liquid metal bubble column reactor, as developed at the Karlsruhe Institute of Technology in recent years. Part I of this contribution described the motivation and the methodology of this study, as well as a significant scale-up, and discussed its results for pure methane pyrolysis. Here in part II, two additional experimental campaigns with methane–ethane mixtures (MEMs) and high-calorific natural gas (nGH) will be presented and discussed for the first time, using the up-scaled liquid metal bubble column reactor. It could be proven that an MEM as the feed gas led to an increase in methane conversion at low temperatures, which is consistent with the literature data. The nGH pyrolysis confirms this trend and also results in a significant rise in methane conversion compared to pure methane pyrolysis. Furthermore, the nGH pyrolysis leads to an increased methane conversion even at higher temperatures compared to MEM pyrolysis. Additionally, both MEM and nGH pyrolysis also showed a shift in the formation of by-products toward lower temperatures. [ABSTRACT FROM AUTHOR]

Hydrogen is not only an important industrial chemical but also an energy carrier with increasing demand. However, the current production techniques are based on technologies that result in massive CO2 emissions. In contrast, the pyrolysis of alkanes in a liquid metal bubble column reactor does not lead to direct CO2 emissions. In order to transfer this technology from lab-scale to industrial applications, it has to be scaled up and the influences of the most common constituent of natural gas on the pyrolysis process have to be determined. For this study, the liquid metal bubble column technology developed at the KIT was scaled up by a factor of 3.75, referred to as the reactor volume. In this article, the experimental setup containing the reactor is described in detail. In addition, new methods for the evaluation of experimental data will be presented. The reactor, as well as the experimental results from pure methane pyrolysis (PM), will be compared to the previous generation of reactors in terms of methane conversion. It could be proven that scaling up the reactor volume did not result in a decrease in methane conversion. For part II of this publication, methane-ethane (MEM) gas mixtures and high calorific natural gas (nGH) were pyrolyzed, and the results were discussed on the basis of the present part I. [ABSTRACT FROM AUTHOR]

This article is devoted to the study of natural gas production by such methods as hydraulic fracturing, drilling, and underwater extraction. The authors analyzed the dynamics of gas production in Russia from old and new wells, as well as recovered from inactive wells, during the period from 2012 to 2021. Mathematical models have been selected to accurately represent the changes in the parameters under study. A forecast for natural gas production in 2025 has also been made, indicating an increase in natural gas production through hydraulic fracturing, drilling, and underwater extraction methods. [ABSTRACT FROM AUTHOR]

Biomass burning is an important component of the Earth system in terms of global biogeochemistry, atmospheric composition, climate, terrestrial ecology, and land use. This study examines published ice core trace gas measurements of acetylene, ethane, and methane, which have been used as proxies for paleofire emissions. We investigate the consistency of these records for the past 1,000 years in terms of (1) temporal trends in global fire emissions and (2) quantitative estimates for changes in global burning (dry matter burned per year). Three-dimensional transport and box models were used to construct emissions scenarios for the trace gases consistent with each ice core record. Burning histories were inferred from trace gas emissions by accounting for biome-specific emission factors for each trace gas. The temporal trends in fire inferred from the trace gases are in reasonable agreement, with a large decline in biomass burning emissions from the Medieval Period (MP: 1000–1500 CE) to the Little Ice Age (LIA: 1650–1750 CE). However, the three trace gas ice core records do not yield a consistent fire history, even assuming dramatic (and unrealistic) changes in the spatial distribution of fire and biomes. Substantial changes in other factors such as meteorological transport or atmospheric photochemical lifetimes appear to be required to reconcile the trace gas records.

Aim: The aim of the article is to review information about motor vehicles that use alternative propulsion systems (in this case, electric propulsion) and the risks associated with their use. The discussion of these issues is crucial for undertaking rescue and firefighting operations during incidents (fires, local emergencies) involving alternatively powered vehicles and the effectiveness of these operations. Knowledge in the areas of: hazard identification, improvement of rescue technologies, necessary devices and equipment for effective rescue and firefighting operations during traffic incidents, including fires, with the involvement of vehicles with alternative propulsion systems can be gained from both theoretical and empirical studies. Introduction: Technical and technological advances in the area of drives used in vehicles and machinery pose new challenges for fire protection. They concern, among other things, the technology of rescue operations during fires and traffic accidents involving such vehicles, as well as ensuring fire safety when operating and storing them in buildings, garages and parking areas, and during charging. Methodology: The article was prepared based on national and foreign sources, literature on the subject, research results and the authors’ diverse experiences. It describes the current state of knowledge in terms of hazards and how to deal with them during rescue and firefighting operations against incidents involving alternatively powered vehicles. Conclusions: The number of motor vehicles in Poland and other countries continues to grow, and together with it also the number of vehicles equipped with alternative drives to internal combustion engines (gasoline, diesel). An analysis of the literature on the subject, available research results, as well as individual incidents, lead to the reasonable conclusion that the risks during rescue and firefighting operations associated with the incidents involving electric and hybrid vehicles are no greater than for conventionally powered vehicles. They are different to some extent, which is due in particular to the used power system, which is based on energy storage devices – batteries. Keywords: alternative propulsion, CNG, LNG, methane, LPG, ethane, propane, hybrid propulsion, electric vehicles, fuel cell, rescue, rescue and firefighting operations

Glycerin, a low-valued waste from biodiesel production, and dopamine were used as precursors for adsorbent materials. The study is centered on the preparation and application of microporous activated carbon as adsorbent materials in the separation of ethane/ethylene and of gases that are natural gas or landfill gas components (ethane/methane and carbon dioxide/methane). The activated carbons were produced by the following sequence reactions: facile carbonization of a glycerin/dopamine mixture and chemical activation. Dopamine allowed the introduction of nitrogenated groups that improved the selectivity of the separations. The activating agent was KOH, but its mass ratio was kept lower than one to improve the sustainability of the final materials. The solids were characterized by N2 adsorption/desorption isotherms, SEM, FTIR spectroscopy, elemental analysis, and point of zero charges (pHPZC). The order for adsorption of the different adsorbates (in mmolg−1) on the most well performing material—Gdop0.75—is methane (2.5) < carbon dioxide (5.0) < ethylene (8.6) < ethane (8.9). [ABSTRACT FROM AUTHOR]

It is predictable that hydrogen gas will be used as the common main energy supply instead of fossil fuels in the near future. Studying hydrogen-production by using hydrogen-rich materials as a source of hydrogen on metal-free catalysts may be worthwhile. We studied the adsorption of ethane, as a hydrogen-rich molecule, on the one, two and three aluminum-doped boron nitride nanotubes using density functional theory. The interactions between any possible sides of ethane and any possible sites on Al B -doped BNNT were studied. The only adsorption has occurred from the carbon atom side of the ethane molecule on the doped aluminum atom site of the BNNT. After the adsorption process, the possible configurations of the intermediates and transition states to receive the decomposition reaction pathway of the ethane molecule were surveyed. The results showed that the ethane molecule was decomposed only on the two aluminum-doped BNNT to four hydrogen atoms. Ethane molecule could be adsorbed from its carbon atom on aluminum-doped BNNT and the adsorption process is exothermic. Also, the structure where two boron atoms in one honeycomb of boron nitride nanotube were replaced with two aluminum atoms has suitable activity and could decompose the ethane molecule into four adsorbed hydrogen atoms and acetylene molecule. Thus, the aluminum atoms could improve the performance of the boron nitride nanotube as a catalyst. [ABSTRACT FROM AUTHOR]

Ethylene (C2H4) is a major chemical for the modern society, and new technologies for its production are of strategic importance globally. Recently, oxidative dehydrogenation of ethane (C2H6) using CO2 as a milder oxidant (CO2‐ODH) is proposed as a potential way for C2H4 production, and development of effective catalysts for the process is drawing wide attention. Here, we report on a facilely prepared ZSM‐5 supported Zn system, i. e., ZnZSM‐5, which showed great promise in CO2‐ODH. Samples with different Zn loadings were prepared and evaluated, and the highest performance was obtained over 0.05ZnZSM‐5 at 700 °C and a CO2:C2H6 feeding ratio of 5 : 1. During 340 min TOS, the C2H6 conversion decreased moderately from 36.2 % to 23.1 %, and the C2H4 yield stabilized at 21.9 % to 27.9 %. Based on systematic characterization and investigation of reaction conditions, the structure‐performance relationship and reaction network were discussed in detail. [ABSTRACT FROM AUTHOR]

Ethylene (C2H4) is a major chemical for the modern society, and new technologies for its production are of strategic importance globally. Recently, oxidative dehydrogenation of ethane (C2H6) using CO2 as a milder oxidant (CO2‐ODH) is proposed as a potential way for C2H4 production, and development of effective catalysts for the process is drawing wide attention. Here, we report on a facilely prepared ZSM‐5 supported Zn system, i. e., ZnZSM‐5, which showed great promise in CO2‐ODH. Samples with different Zn loadings were prepared and evaluated, and the highest performance was obtained over 0.05ZnZSM‐5 at 700 °C and a CO2:C2H6 feeding ratio of 5 : 1. During 340 min TOS, the C2H6 conversion decreased moderately from 36.2 % to 23.1 %, and the C2H4 yield stabilized at 21.9 % to 27.9 %. Based on systematic characterization and investigation of reaction conditions, the structure‐performance relationship and reaction network were discussed in detail. [ABSTRACT FROM AUTHOR]

Adsorptive separation is an energy‐efficient alternative, but its advancement has been hindered by the challenge of industrially potential adsorbents development. Herein, a novel ultra‐microporous metal‐organic framework ZU‐901 is designed that satisfies the basic criteria raised by ethylene/ethane (C2H4/C2H6) pressure swing adsorption (PSA). ZU‐901 exhibits an "S" shaped C2H4 curve with high sorbent selection parameter (65) and could be mildly regenerated. Through green aqueous‐phase synthesis, ZU‐901 is easily scalable with 99 % yield, and it is stable in water, acid, basic solutions and cycling breakthrough experiments. Polymer‐grade C2H4 (99.51 %) could be obtained via a simulating two‐bed PSA process, and the corresponding energy consumption is only 1/10 of that of simulating cryogenic distillation. Our work has demonstrated the great potential of pore engineering in designing porous materials with desired adsorption and desorption behavior to implement an efficient PSA process. [ABSTRACT FROM AUTHOR]

Methane is the fundamental raw material of the C1 chemical industry, with abundant reserves. Its direct conversion into high-value-added chemicals has great scientific significance and broad commercial potential for the efficient use of methane resources. However, it is difficult to convert methane into more useful hydrocarbons and hydrogen, as the reaction usually requires external energy to overcome thermodynamic limitations. Non-oxidative coupling of methane to produce ethane and hydrogen is a promising supply technology. Catalysts which can be adapted to various energy sources are key to this technology. In recent years, considerable progress has been made in the design and application of these thermal and photocatalysts. This review outlines some typical catalysts, and reviews the progress in the understanding of reaction mechanisms. Finally, suggestions for the development of high-selectivity and high-stability catalysts for the future are presented. [ABSTRACT FROM AUTHOR]

In this work, 532 nm laser was used as the pump source and pressurized ethane was used as Raman active medium; 631.3 nm first Stokes (S1) and 776.0 nm second Stokes (S2) Raman lasers were generated. By the optimization of ethane pressure and focus lens, S2 and backwards first Stokes Raman conversion could be reduced, while the conversion of S1 could be improved. Under 2.0 MPa ethane and focal length of 1.5 m, the maximum S1 conversion efficiency of 84.5% was achieved. Up to 68.7 mJ S1 Raman laser was obtained, and the corresponding peak power is 17.2 MW. By the comparison of the threshold of methane Raman laser, Raman gain coefficients of ethane were estimated to be 0.50 × 10−12 m/W at 0.5 MPa and 0.76 × 10–12 m/W at 1.4 MPa ethane respectively.

Selective adsorption using nanoporous materials is an efficient strategy for separating gas mixtures. In a nanoporous material, pores can exist in different shapes and can have different degrees of inter-connectivity. In recent studies, both pore connectivity and tortuosity have been found to affect the adsorption and dynamical properties of ethane and CO2 in silicalite differently. Here, using Monte Carlo simulations, we investigate if these two attributes can affect the selective adsorption of one component from a mixture of ethane and CO2 in silicalite. For this, the adsorption of an equimolar mixture of ethane and CO2 is simulated in 12 models of silicalite—SnZm (n, m = 0, 1, 2, 3 or 4; with n and m denoting, respectively, the fraction (out of 4) of straight and zigzag channels of silicalite that are available for adsorption)—differing in degrees of pore connectivity and tortuosity. The adsorption selectivity in this system is found to exhibit a reversal with the adsorption dominated by ethane at low pressures (below ~1 atm) and by CO2 at higher pressures (above ~10 atm). Pore connectivity is found to suppress the selective adsorption of CO2 at higher pressures and also shifts the selectivity reversal to higher pressures. The selectivity reversal results from a competition between the polarizability-affected adsorption at lower pressures and efficient packing at higher pressures. The efficient packing of CO2 is a compounded effect resulting from the larger effective pore volume available for CO2 due to its stronger interaction with the pore surface and smaller molecular volume. CO2 molecules show a preference to adsorb in non-tortuous pores, and this preference is found to be stronger in the presence of ethane. The effects of pore connectivity and tortuosity elucidated here should be applicable to a wide range of natural and engineered nanoporous materials, and this knowledge could be used to identify materials with better capability for separating and storing CO2 based on their pore attributes.

NiO-based catalysts are among the most active and selective catalytic systems for low-temperature oxidative dehydrogenation (ODH) of ethane into ethylene and, therefore, they have been extensively studied in the last twenty-five years. This paper reviews the most relevant works focusing on NiO-based catalysts for ethane ODH, including promoted and unpromoted, bulk and supported NiO. The effects of the nature of the promoter and of the support together with the influence of the method of preparation used on their activity in ethane ODH are discussed in detail as they were shown to be key factors controlling the catalytic performance, including the catalyst stability. The reaction mechanism involved in ethane ODH reaction over NiO-based catalysts is also presented and discussed.

Biomass burning drives changes in greenhouse gases, climate-forcing aerosols, and global atmospheric chemistry. There is controversy about the magnitude and timing of changes in biomass burning emissions on millennial time scales from preindustrial to present and about the relative importance of climate change and human activities as the underlying cause. Biomass burning is one of two notable sources of ethane in the preindustrial atmosphere. Here, we present ice core ethane measurements from Antarctica and Greenland that contain information about changes in biomass burning emissions since 1000 CE (Common Era). The biomass burning emissions of ethane during the Medieval Period (1000-1500 CE) were higher than present day and declined sharply to a minimum during the cooler Little Ice Age (1600-1800 CE). Assuming that preindustrial atmospheric reactivity and transport were the same as in the modern atmosphere, we estimate that biomass burning emissions decreased by 30 to 45% from the Medieval Period to the Little Ice Age. The timing and magnitude of this decline in biomass burning emissions is consistent with that inferred from ice core methane stable carbon isotope ratios but inconsistent with histories based on sedimentary charcoal and ice core carbon monoxide measurements. This study demonstrates that biomass burning emissions have exceeded modern levels in the past and may be highly sensitive to changes in climate.

Two C2H6‐selective metal‐organic framework (MOF) adsorbents with ultrahigh stability, high surface areas, and suitable pore size have been designed and synthesized for one‐step separation of ethane/ethylene (C2H6/C2H4) under humid conditions to produce polymer‐grade pure C2H4. Experimental results reveal that these two MOFs not only adsorb a high amount of C2H6 but also display good C2H6/C2H4 selectivity verified by fixed bed column breakthrough experiments. Most importantly, the good water stability and hydrophobic pore environments make these two MOFs capable of efficiently separating C2H6/C2H4 under humid conditions, exhibiting the benchmark performance among all reported adsorbents for separation of C2H6/C2H4 under humid conditions. Moreover, the affinity sites and their static adsorption energies were successfully revealed by single crystal data and computation studies. Adsorbents described in this work can be used to address major chemical industrial challenges. [ABSTRACT FROM AUTHOR]

Hydrate–liquid–vapour (HLV) equilibrium of aqueous clathrates formed from gas mixtures can be complex compared to hydrates formed with single guests. Typically, pressure and temperature are controlled to obtain these data, but for multicomponent systems, it is necessary to control/report more intensive variables, namely, composition. Metastability, manifested as impractically long experimental times, has been reported to be a challenge with some multicomponent systems. We present HLV equilibrium conditions of two ternary gas mixtures: methane + ethane + propane (90:7:3 molar ratio) and methane + propane + carbon dioxide (55:5:40 molar ratio). Conditions varied in the temperature range of 275–285 K and the pressure range of 1.24–4.75 MPa. Experimental standard uncertainties were on average 0.10 K and 0.005 MPa for methane + ethane + propane and 0.19 K and 0.005 MPa for methane + propane + carbon dioxide. Our technique allowed us to bypass the limitations reported in the literature and provided fast, reproducible HLV equilibria for gas‐dominated systems. [ABSTRACT FROM AUTHOR]

As a novel reaction mode of oxidative dehydrogenation of ethane to ethylene, the chemical looping oxidative dehydrogenation (CL-ODH) of ethane to ethylene has attracted much attention. Instead of using gaseous oxygen, CL-ODH uses lattice oxygen in an oxygen carrier or redox catalyst to facilitate the ODH reaction. In this paper, a perovskite type redox catalyst LaMnO3+δ was used as a substrate, Ce3+ with different proportions was introduced into its A site, and its CL-ODH reaction performance for ethane was studied. The results showed that the ratio of Mn4+/Mn3+ on the surface of Ce-modified samples decreased significantly, and the lattice oxygen species in the bulk phase increased; these were the main reasons for improving ethylene selectivity. La0.7Ce0.3MnO3 showed the best performance during the ODH reaction and showed good stability in twenty redox cycle tests. [ABSTRACT FROM AUTHOR]

Ozone addition is a promising way to control and monitor the combustion process, e.g., enhancing the low-temperature oxidation reaction. This paper studied the ozone-initiated low-temperature oxidation of methane and ethane in a jet-stirred reactor (JSR) at atmospheric pressure. For the first time, we observed that the low-temperature oxidation of methane and ethane started ca. 450 K. Dozens of low-temperature oxidation products, which are dominantly oxygenated species, were identified and quantified by synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS). These data are valuable for evaluating the C 1 –C 2 chemistry of base models. NUIGMech1.1 was used to simulate the experimental data in this work. The results reveal that the model can predict methane conversion, but a large deviation is observed for the intermediate species. In the case of ethane, NUIGMech1.1 overpredicts the low-temperature reactivity of ethane. We found that the reaction mechanism of the alkylperoxy radicals (CH 3 Ȯ 2 and C 2 H 5 Ȯ 2) is crucial in accurately predicting the low-temperature oxidation chemistry of methane and ethane. The bimolecular reactions of the alkylperoxy radicals with Ö atoms and ȮH and HȮ 2 radicals, as well as the self and cross reactions of the alkylperoxy radicals, determine the balance of the radical pool of Ö, ȮH, and HȮ 2 , and subsequently the fuel reactivity and the formation of the oxidation intermediates. This work provides new insights into the reaction mechanism of the key intermediates in the base model for chemically sensitized low-temperature fuel oxidation that need to be thoroughly studied in the future. [ABSTRACT FROM AUTHOR]

The reference interaction site model (RISM) theory has been applied for methane-like, ethane-like molecules and methane-ethane-like mixture. The Lennard-Jones potential is used to describe a molecular interaction. The Percus-Yevick and Martynov-Sarkisov bridge functions have been employed. For reduced temperatures of 2.5 and 5.15, the configurational internal energy for the systems has been computed as a function of a reduced number density. A mole fractions of the methane-like molecule for mixture are 0.25, 0.5 and 0.75. For the densities less than 0.6, results obtained from both bridge functions are almost indistinguishable, and for densities from 0.6 to 0.9, a minor discrepancy has been shown up. For equimolar mixture, and for density of 0.1 to 0.8 the computed findings have been compared with accurate ones obtained with a molecular dynamics (MD) simulation and a maximum deviation is 2%. Moreover, the structure for the mixture computed with the RISM equation presents good agreement with that from the MD simulation. [ABSTRACT FROM AUTHOR]

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Comparative results of studying the oxidative dehydrogenation of ethane (ODE) on catalytic vanadium-phosphorus oxide systems deposited by the molecular layering method on the surface of oxide supports (Al2O3, SiO2) have been presented. It has been found that the highest activity in ODE and selectivity for ethylene are exhibited by vanadium-phosphorus-containing catalysts. The influence of the acidity of catalytic systems on the activity and selectivity of the process has been revealed. The selectivity of the ODE process for ethylene reaches 90%. An increase in the oxygen concentration in the initial mixture from 3.5 to 20% leads mainly to a decrease in the selectivity of the ODE process with respect to the ethylene yield. [ABSTRACT FROM AUTHOR]

In search of a more effective process of ethane oxidative hydrogenation, different operation modes (thermal and microwave heating) are compared. The catalyst Mo1-V0.3-Te0.13-Nb0.11-Ox was prepared by hydrothermal synthesis and characterized by a set of physicochemical methods (XRD, N2 adsorption, SEM, EDX). The direct microwave heating of the catalyst layer is proposed as an alternative way of energy-saving ethane-to-ethylene oxidation by a Mo-V-Te-Nb-Ox system. A substantial decrease in the reactor temperature upon the microwave-assisted process is accompanied by extremely high catalyst selectivity, which remains at a very high level of 98+%. [ABSTRACT FROM AUTHOR]

The process of oxidative dehydrogenation of ethane (ODE) at an elevated pressure over a MoVNbTeOx mixed oxide catalyst is studied. It is found that when the reaction is carried out at 280°C, the fraction of the total amount of reacted oxygen consumed for the formation of ethylene decreases from 100 to 68% with the increase in pressure from 0.1 to 10.0 MPa, which may indicate an increase in the role of chemisorbed oxygen in the ODE process at a high pressure. Here, the productivity with respect to ethylene at 280°C and 10.0 MPa is higher in comparison with the value obtained at 360°C and 0.1 MPa. [ABSTRACT FROM AUTHOR]

Clarifying alkane gas condensation characteristics is crucial to designing and optimizing liquefaction heat exchangers, which imposes higher demands on the microscopic understanding of alkane heterogeneous condensation. Thus, in this study, the condensation process of methane nucleation under different driving forces is investigated by molecular dynamics (MD) simulations. The dynamics characteristics of nucleation in methane heterogeneous condensation are analyzed by varying initial gas-phase pressure, cold wall temperature, and ethane content. The results showed that increasing the initial gas-phase pressure enhances intermolecular interactions, which alter the cluster formation path and significantly increase the methane gas nucleation rate from 1.997 × 1033/(m3·s) to 1.068 × 1034/(m3·s). While lowering the cold wall temperature promotes condensation by weakening the thermal motion of the gas molecules. Once condensation nuclei form in the system, the lower temperature conditions from lowering the cold wall temperature result in a higher growth rate of the clusters. Additionally, the addition of easily condensable component ethane can improve the condensation nucleation characteristics of low-saturated methane gas, facilitating the liquefaction of methane. This study aims to provide a microscopic understanding of the advancement of gas liquefaction technology by investigating the heterogeneous nucleation of alkane under different conditions from a microscopic perspective. • Effects of pressure and temperature on methane condensation are analyzed. • Mechanism of ethane promoting low-saturation methane condensation is investigated. • Mechanisms of different driving forces on condensation nucleation are studied. [ABSTRACT FROM AUTHOR]

The effect of the CO 2 :C 2 H 6 feed ratio, the relative Lewis acidity of reducible and unreducible catalytically active metal oxide supports with and without Fe 3 Ni 1 alloy nanoparticles on the activity, selectivity and stability for the CO 2 -mediated oxidative dehydrogenation of ethane (CO 2 -ODHE) is investigated. To circumvent the influence of the typically dissimilar textural properties of the supports in bulk form, overlayer oxide supports of V, Cr, Ga, Ti or Sm coated on a common γ-Al 2 O 3 carrier were employed. Separately, (Ni 0.75 Fe 0.25)Fe 2 O 4 precursor nanoparticles were synthesized via a nonaqueous surfactant-free method, sonication-deposited onto supports and reduced in situ into an Fe 3 Ni 1 alloy microstructure of bcc and fcc mixed phases captured with in situ XRD. When exposed to carbon dioxide at 255 °C, a selective re-oxidation of the bcc phase via CO 2 dissociation is observed, while the fcc phase stays stable and only partially re-oxidizes above 525 °C. Upon exposure to CO 2 -ODHE conditions, the initial activity of the bare supports increases with increasing acid site strength, but this activity is rapidly lost in case of the strongly acidic supports. Comparison of the C 2 H 4 and CO selectivity indicate direct dehydrogenation is preferred over the oxidative dehydrogenation pathway and is initially occurring in combination with some CO-forming routes, possibly the dry reforming of C 2 H 6. This CO forming route is significant over the most acidic and reducible VO x @Al 2 O 3 support in the early stages of operation. The addition of the Fe 3 Ni alloy increases the conversions of both C 2 H 6 and CO 2 across all supports, with a notably stronger effect observed on CO 2 conversion especially over the highly acidic and reducible VO x @Al 2 O 3 and CrO x @Al 2 O 3. As a result, the CO selectivity is increased due to ethane dry reforming activity over the latter supports while CO 2 -ODHE activity is observed over the supports with intermediate and weak acid sites. [Display omitted] • The initial activity of bare supports increases with acid site strength but is lost rapidly for strongly acidic supports. • Direct dehydrogenation with dry reforming are dominant initially and increase with the bare support acidity. • Supported catalysts show improved activity with increasing support acidity especially in CO 2 conversion. • Improved activity, especially on strongly acidic supports, results in DRE activity and weakening acidity promotes CO 2 -ODHE. • CO 2 -rich feed improves the catalyst stability and yields owing to promotion of the reverse Boudouard reaction. [ABSTRACT FROM AUTHOR]

Developing C 2 H 6 -selective adsorbents for efficient separation of C 2 H 6 /C 2 H 4 is of great significance for the petrochemical industry. Numerous C 2 H 6 -selective adsorbents have been created, but their applicability in real-world industrial settings is severely constrained by their unscalable production and generally low stability (particularly water resistance). Herein, we proposed a series of C 2 H 6 -selective adsorbents CUPMOF-2-M (M = Zn, Mn, Cu, Mg), in which CUPMOF-2-Zn (also termed MET-6) not only possesses good C 2 H 6 -selective separation effect but super-hydrophobicity and low cost. At 298 K and 80 % relative humidity, CUPMOF-2-Zn only adsorbs 0.4 mmol·g−1 of water, outperforming all previously reported C 2 H 6 -selective materials in terms of hydrophobicity. Moreover, dynamic breakthrough experiments solidly demonstrated that CUPMOF-2-Zn can efficiently separate C 2 H 6 /C 2 H 4 in high humidity conditions. More importantly, CUPMOF-2-Zn can be synthesized in a large-scale at room temperature (one batch 10 kg), which is essential to industrial implementation for separation of C 2 H 6 /C 2 H 4. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • C 2 H 6 + C 3 H 8 mixtures were investigated as a potential 'gas-phase modulator'. • Improved thermodynamic stability was observed by using C 2 H 6 + C 3 H 8 mixtures. • The maximum composition of H 2 in the C 2 H 6 + C 3 H 8 + H 2 hydrate was 44.37%. • Enhanced gas uptake and H 2 split fraction was observed as injected H 2 increased. As the global climate crisis intensifies with rising carbon dioxide (CO 2) concentrations, blue hydrogen (H 2) produced through the integration of CO 2 capture technologies is emerging as a promising alternative energy source and is challenging traditional fossil fuels in the de-fossilization paradigm. Gas hydrate could be one of the feasible storage medium for energy-efficient H 2 storage, due to its potential for eco-friendly features and high H 2 storage capacity. However, extreme thermodynamic formation conditions for pure H 2 hydrate need to be mitigated for practical application. Here, we demonstrate a novel approach by blending a 'gas-phase modulator' with H 2 , specifically a C 2 H 6 (70%) + C 3 H 8 (30%), to enable hydrate-based H 2 storage under moderate thermodynamic formation conditions. In this study, we systematically examined thermodynamic stability, crystallographic structure, guest occupation behavior, and the formation kinetics of the C 2 H 6 + C 3 H 8 + H 2 hydrates by varying the H 2 composition. The results revealed that the C 2 H 6 + C 3 H 8 mixture played a notable role in promoting thermodynamic formation condition of H 2 hydrates. The mixed C 2 H 6 + C 3 H 8 + H 2 hydrates were predominantly comprised of sII hydrate, with small amount of sI hydrate. Considering the small to large cage ratio of sI and sII hydrate, this observation indicates a significant advantage for H 2 storage due to primarily occupation behavior of H 2 into the small cages. In addition, as the H 2 composition in the feed gas increased, we confirmed that not only that H 2 storage in the hydrate was enhanced but also that the degree of the H 2 enclathration ratio into the hydrate was elevated. Moreover, the maximum composition of H 2 in the C 2 H 6 (14%) + C 3 H 8 (6%) + H 2 (80%) hydrate was 44.37%. Hence, we believe that our findings can contribute valuable insights into the potential application of gas-phase modulators for hydrate-based H 2 storage, we emphasize that C 2 H 6 + C 3 H 8 can act as a potential gas-phase modulator for energy-efficient H 2 storage. [ABSTRACT FROM AUTHOR]

Ethylene production has a negative environmental impact, with its separation step being one of the major contributors of pollution. This has encouraged the search for energy-efficient alternatives, among which the adsorptive separation of ethane and ethylene stands out. ZIF-8 is a molecular sieve that is potentially useful for this purpose. It is selective to ethane, an exceptional property that remains unexplained. Furthermore, the adsorption of ethane and ethylene above room temperature, such as at steam cracking process outlet temperatures, has not been addressed either. This work aims to fill this knowledge gap by combining experiments at very low volumetric fillings with density–functional theory modelling methods. Adsorption isotherms of ethane and ethylene on ZIF-8 at pressures below 0.3 bar and 311 K, 333 K, and 363 K were measured using zero-length column chromatography. The low-pressure domain of the isotherms contains information on the interactions between the adsorbate molecules and the adsorbent. This favors the understanding of their macroscopic behavior from simulations at the atomic level. The isosteric enthalpy of adsorption of ethane remained constant at approximately −10 kJ/mol. In contrast, the isosteric enthalpy of adsorption of ethylene decreased from −4 kJ/mol to values akin to those of ethane as temperature increased. ZIF-8 selectivity to ethane, estimated from ideal adsorbed solution theory, decreased from 2.8 to 2.0 with increasing pressure up to 0.19 bar. Quantum mechanical modelling suggested that ethylene had minimal interactions with ZIF-8, while ethane formed hydrogen bonds with nitrogen atoms within its structure. The findings of this research are a platform for designing new systems for the adsorptive separation of ethane and ethylene and thus, reducing the environmental impact of ethylene production.