Hydration Of Carbon Dioxide Research Articles

Effect of different salts on the kinetic parameters of the carbon dioxide hydrate formation

In this study, the effects of sodium chloride (NaCl), potassium chloride (KCl), magnesium chloride (MgCl2), and calcium chloride (CaCl2) on the kinetic parameters of carbon dioxide (CO2) hydrate formation including induction time, amount of gas consumption, rate of gas consumption and storage capacity were experimentally studied. Aqueous solutions with the ion concentration same as the Persian Gulf Seawater were prepared and all the experiments were conducted at a temperature of 274.15 K and pressure of 3.5 MPa. The results showed that salts have an inhibitory effect on the kinetic parameters of CO2 hydrate formation by reducing CO2 solubility in water and electrostatic interaction between water molecules and ions. The intensity of ion inhibition depends on the ion size, ion charge, ion concentration, and the kosmotropic and chaotropic properties of ions. Examination of the kinetic parameters of CO2 hydrate formation in saline solutions with a constant concentration of 1000 mg/L of each ion showed that the Mg2+ has the greatest inhibitory effect on the kinetic parameters by increasing the induction time by 110.71% and reducing gas consumption, rate of gas consumption, and storage capacity by 48.21%, 82.14%, and 68.75%, respectively compared to pure water. The results showed that the inhibition effect of salt ions on the CO2 hydrate formation is in the following order: Mg2+> Ca2+>Na+>K+.

Amino Acid-Mediated Synthesis of the ZIF-8 Nanozyme That Reproduces Both the Zinc-Coordinated Active Center and Hydrophobic Pocket of Natural Carbonic Anhydrase.

The zeolitic imidazolate framework-8 (ZIF-8) nanozyme has been synthesized using hydrophobic amino acid (AA) to regulate crystal growth. The as-synthesized ZIF-8 reproduces both the structural and functional properties of natural carbonic anhydrase (CA). Structurally, Zn2+/2-methylimidazole coordinated units mimic very well the active center of CA while the hydrophobic microdomains of the adsorbed AA simulate the CA hydrophobic pocket. Functionally, the nanozymes show excellent CA-like esterase activity by giving specific enzyme activity of 0.22 U mg-1 at 25 °C in the case of Val-ZIF-8. More strikingly, such nanozymes are superior to natural CA by having excellent hydrothermal stability, which can give highly enhanced esterase activity with increasing temperature. The specific enzyme activity of Val-ZIF-8 at 80 °C is about 25 times higher than that at 25 °C. In addition, AA-ZIF-8 also shows an excellent catalytic efficiency toward carbon dioxide (CO2) hydration. This study puts forward the important role of hydrophobic microdomains in biomimetic nanozymes for the first time and develops a facile and mild method for the synthesis of nanozymes with controlled morphology and size to achieve excellent catalytic efficiency.

Instrumental Methods for Cage Occupancy Estimation of Gas Hydrate

Studies revealed that gas hydrate cages, especially small cages, are incompletely filled with guest gas molecules, primarily associated with pressure and gas composition. The ratio of hydrate cages occupied by guest molecules, defined as cage occupancy, is a critical parameter to estimate the resource amount of a natural gas hydrate reservoir and evaluate the storage capacity of methane or hydrogen hydrate as an energy storage medium and carbon dioxide hydrate as a carbon sequestration matrix. As the result, methods have been developed to investigate the cage occupancy of gas hydrate. In this review, several instrument methods widely applied for gas hydrate analysis are introduced, including Raman, NMR, XRD, neutron diffraction, and the approaches to estimate cage occupancy are summarized.

Insights into carbon dioxide hydrate formation, fluid type, and agglomeration in the system with or without tween-80

In this work, the flow of carbon dioxide (CO2) hydrate slurry is systematically investigated by analyzing its rheological behavior, apparent viscosity, and crystal shape. The results show that blocking is easy to occur in the pure water system, while no blockage is observed from the system containing Tween-80. Besides, we confirm that the hydrate slurry formed in the pure water system is a dilatant fluid with shear-thickening behavior. However, that obtained from the system containing Tween-80 are pseudoplastic fluids with shear-thinning behavior. The time development of hydrate slurry flow in the system with or without Tween-80 showed that the shear-thinning behavior is a key factor in preventing the hydrate slurry from blockage. In addition, in the presence of Tween-80, hydrates will form on the surface of the bubble. These hydrates are easily dispersed on top of the liquid phase and will not adhere to the top wall of the pipeline. However, in pure water, a dense adhesive layer is observed on the top of the pipeline, which will reduce the flow area in the pipeline, increasing the flow resistance. Overall, the main role of Tween-80 in preventing hydrates from aggregation includes two aspects, (1) changing the type of fluid from dilatant to pseudoplastic; (2) providing bubbles for hydrate formation. The addition of defoamer(BK601) will reduce the Tween-80′s effects in preventing hydrates by reducing shear-thinning behavior and the amount of bubbles.

Sequestration and Storage of Carbon Dioxide Using Hydrate Formation Method in the Presence of Copper Oxide Nanoparticles

The nanofluid-based gas hydrate formation process employing copper oxide (CuO) nanoparticles have been experimentally investigated in this work. Different concentrations of nanofluids are injected into the reactor at the operating condition of 29 bar, 274.15 K, and impeller speed of 100 rpm. It was observed that the kinetics of the carbon dioxide hydrate formation process was greatly affected by the nanoparticles. The remarkable point was that at a very low concentration of 20 ppm, a considerable improvement on the carbon dioxide hydrate formation kinetic without using any surfactant was obtained. At the concentration of 20 ppm, the values of the initial rate of hydrate formation, growth time, and induction time were 0.0495, 194.5, and 4.4 min, respectively, which these results can be of great importance for the use of carbon dioxide hydrate in various industries. The results indicated that the kinetics of gas hydrate formation was also severely influenced by the impeller speed and initial gas pressure. The rate of CO2 captured in the hydrate crystalline lattice is also modeled by the first-order kinetic model. It was seen that this model can be used to predict the rate of hydrate formation with considerable accuracy.

Effect of sodium tripolyphosphate (STPP) and tetrasodium pyrophosphate (TSPP) on the formation kinetics of CO2 hydrate in bulk and porous media in the presence of pure water and seawater relevant for CO2 sequestration

Enhanced kinetics of carbon dioxide (CO2) hydrate formation will assist in developing technologies for CO2 gas storage, carbon capture and sequestration (CCS), and potentially for methane production from natural gas hydrates. The present work is focused on understanding the kinetics of CO2 hydrate formation in both bulk and porous media with pure water and seawater under the influence of non-toxic and low-cost inorganic emulsifiers or builders. Sodium tripolyphosphate (STPP) and tetrasodium pyrophosphate (TSPP) was used in a very low concentration of 0.2 wt.% to promote its economic viability. The experiments were carried out in a 300 mL stirred tank reactor and 100 mL porous bed reactor with an initial pressure of 3.5 MPa and 274.65 K with pure water and seawater, respectively. The porous bed was made with 0.15 mm silica sand with 70% water saturation. Both STPP and TSPP showed significant improvement in induction time for CO2 hydrate formation. Moreover, STPP showed reasonable enhancement in CO2 gas uptake compared to TSPP in both bulk and porous bed with both pure water and seawater. The average rate of hydrate formation was also better for STPP with multiple growth peaks. The results obtained will enhance hydrate-based technologies for efficient CO2 sequestration in shallow subsea sediments.

Experimental determination of dissociation temperatures and enthalpies of methane, ethane and carbon dioxide hydrates up to 90 MPa by using a multicycle calorimetric procedure

This work presents the application of a multicycle procedure to determine the dissociation temperature and enthalpy of gas hydrates using high-pressure microcalorimetry (HP-µDSC). In the multicycle procedure, a sample of water in contact with the gas undergoes successive cooling and warming cycles below hydrate dissociation temperature, increasing the conversion of water into hydrate. This technique has been previously used in literature to increase water conversion during carbon dioxide hydrate formation up to 2.0 MPa, but its applicability has not been assessed for higher pressures and with different guest molecules. New experimental equilibrium data for methane, ethane, and carbon dioxide hydrates were obtained through HP-µDSC up to 90 MPa using the multicycle procedure. The advantages and limitations of the method are discussed. Dissociation temperatures are in good agreement with data previously obtained from a HP-µDSC standard method, which confirms the reliability to determine this property by both methods. Nevertheless, the enthalpy of hydrate dissociation obtained by the direct integration of thermograms provided by the HP-µDSC standard method is not accurate. Thus, it is usually calculated by using the Clapeyron equation from equilibrium temperature and pressure data obtained by the HP-µDSC standard method, as presented in previous work. The new dissociation enthalpies presented in this work were obtained experimentally by direct integration of thermograms using the multicycle procedure, which provides accurate data as the conversion is very high (above 97% of water converts into hydrate), the baselines are clearly established, and no exothermic peak related to metastable phases is observed.

A thermodynamic framework for determination of gas hydrate stability conditions and water activity in ionic liquid aqueous solution

The formation of gas hydrates in pipelines and plugging of the gas flow path are a major cause of operating expenses, safety issues, pressure drop, and fatal accidents. Therefore, the inhibition of gas hydrate formation is of paramount importance. The utilization of a new class of inhibitors such as ionic liquids (ILs) is currently of great interest. In this regard, adjusting water activity in the inhibitor blend (water + IL) is a vital factor. Several models have been developed to calculate the activity of water in the presence of IL(s). The major disadvantage of these models is their correlative basis. This study aimed to propose a rigorous predictive model for the calculation of water activity in the presence of IL(s), which would then be applied in the prediction of the gas hydrate stability conditions. The model is made up of a molecular term (the short-range interactions from Free-Volume-Flory-Huggins (FVFH) activity model) as well as a contribution from ionic interactions as a result of IL(s) dissociation in water (the long-range electrostatic interactions from the extended Debye–Hückel (EDH) model). The overall absolute temperature deviation and the average absolute relative deviation percent in the calculated gas (methane and carbon dioxide) hydrate dissociation temperatures for the whole databank (500 data points including 37 ILs) were found to be 0.61 K and 0.22%, respectively. This proves the superiority of the model over the previous correlative-basis ones. Finally, it is concluded that the higher temperature, the higher the IL(s) concentration, and the lower IL(s) molecular weight(s) result in larger model deviations.

Thermodynamic and Kinetic Description of the Main Effects Related to the Memory Effect during Carbon Dioxide Hydrates Formation in a Confined Environment

This article consists of an experimental description about how the memory effect intervenes on hydrates formation. In particular, carbon dioxide hydrates were formed in a lab–scale apparatus and in presence of demineralized water and a pure quartz porous medium. The same gas-water mixture was used. Half of experiments was carried out in order to ensure that the system retained memory of previous processes, while in the other half, such effect was completely avoided. Experiments were characterized thermodynamically and kinetically. The local conditions, required for hydrates formation, were compared with those of equilibrium. Moreover, the time needed for the process completion and the rate constant trend over time, were defined. The study of these parameters, together with the observation that hydrates formation was quantitatively similar in both types of experiments, allowed to conclude that the memory effect mainly acted as kinetic promoter for carbon dioxide hydrates formation.

Texture, composition and properties of plugs formed by carbon dioxide hydrate and wax

Gas hydrates and wax are the major flow assurance problems for the transportation of produced hydrocarbons through pipelines. However, in most research works both these two problems are studied separately. Although simultaneous precipitation or deposition of these compounds in pipelines can lead to different mitigation/prevention strategies, the investigations in which both these problems are considered simultaneously appeared only recently. There is no information in the literature on the texture/composition and features of decomposition process of mixed wax/hydrate plugs. At the same time, this information could be useful to understand how to treat the problem of formation of these plugs. In this work, three wax/gas hydrate plugs were collected at quasi-static conditions from a water-in-oil emulsion to study their texture, composition and the features of decomposition process. Powder X-ray diffraction and IR (infrared spectroscopy) analyses showed that the plugs consisted of wax and gas hydrate. Thermovolumetric and DSC (Differential Scanning Calorimetry) experiments showed that the main part of gas hydrate in the plugs at the ambient pressure started to decompose at about 268 K. This temperature was higher than the equilibrium temperature of carbon dioxide hydrate at this pressure, indicating that the gas hydrate in the plugs could be effectively preserved at temperatures below the ice melting point (273.2 K). It was found through observation of the hydrate decomposition process in the plugs under the microscope that the gas in the samples released in small bubbles, while the hydrate particles were not visible at this magnification, indicating that the hydrate was indeed highly dispersed in the samples. A residual wax was jelly-like after decomposition of hydrate in all the cases. Rheological experiments showed that the plugs residues after decomposition of the hydrates had higher yield points and viscosities than the initial waxy crude oil originally used for the experiments.

Pharmacological inhibition of carbonic anhydrases ameliorates cognitive dysfunction, rescuing Aβ‐induced neurovascular pathology in vivo

Cerebrovascular dysfunction (CVD) is an early feature of Alzheimer's disease (AD), contributing to the pathology progression, and suggesting a strict association between CVD and neurodegeneration. The majority of AD cases present cerebral amyloid angiopathy (CAA), neuropathological feature characterized by abnormal vasculotropic deposition of amyloid beta, mainly Aβ40. Severe CAA is also induced by familial Aβ variants, such as the Dutch-Q22. Our previous in vitro studies demonstrated that brain vascular amyloidosis elicits mitochondrial dysregulation and caspase-mediated apoptosis, in cells composing the neurovascular unit, including neurons, endothelial, glial and smooth muscle cells. Additionally, we showed that acetazolamide (ATZ) and methazolamide (MTZ), FDA-approved carbonic anhydrase inhibitors (CAIs) which cross the blood-brain barrier (BBB), hamper these detrimental processes. Carbonic anhydrases (CAs) represent a family of metalloenzymes catalyzing the reversible hydration of carbon dioxide, and their inhibition improves cerebral blood flow, vasoreactivity and neuronal excitability, pointing to CAs as CVD targets in AD.We employed Tg-SwDI mice (expressing human amyloid precursor protein, APP, carrying the Swedish, Dutch and Iowa mutations), which develop fibrillar amyloid burden, primarily in the cerebral microvasculature, starting at 6 months. We fed the animals (from 8 to 16 months of age) a CAI-diet, following which we performed behavioral analysis, and harvested the brains for both biochemical and immunohistochemical examination.Compared to untreated Tg mice, ATZ- and MTZ-fed animals showed reduced cognitive impairment, along with decreased vascular Aβ overload and astrogliosis, main pathological hallmarks of the disease. Tg animals exhibited Aβ deposition in endothelial and glial cells, leading to cell-specific caspase-3 activation. Interestingly, CAI-diet reduced endothelial and astrocytic Aβ deposits, and Aβ-induced caspase activation. Interestingly, the augmented expression of cerebral TREM2 and CD68 in CAI-treated mice suggests an attenuated inflammatory response, concomitantly with a boost of the cerebral clearance and active Aβ removal from brain microglia/macrophages, respectively, which may underlie the observed Aβ reduction. Furthermore, preliminary data suggest that both ATZ and MTZ promote microglial endocytosis, possibly facilitating Aβ degradation.CAIs provide neuroprotection, fostering neurovascular and glial physiological functions and clearance mechanisms, and attenuating CVD.

Nucleation and dissociation of carbon dioxide hydrate in the inter- and intra-particle pores of dioctahedral smectite: Mechanistic insights from molecular dynamics simulations

The storage of CO2 in the form of gas hydrate is becoming common place in the field of carbon capture and storage. Natural gas hydrate deposits are typically rich in clay minerals, yet their potential effect on CO2 hydrate nucleation and dissociation is rarely elucidated. In the present work, the nucleation and dissociation of CO2 hydrate in the inter- and intra-particle pores of dioctahedral smectite particles were investigated using molecular dynamics simulations. The results show that the hydrate nucleation clearly occurred in the inter-particle pores, whereas clathrate-like structures were formed in the intra-particle pores or on the edge surface of smectite. The properties of smectite, specifically the layer charge distribution and the type of exchangeable cations, are the main factors affecting the nucleation and dissociation of CO2 hydrate by changing the structural ordering of water molecules. The diffusion of CO2 molecules into the intra-particle pores enhances the formation of clathrate-like structures with increasing water content, but it does not increase the structural ordering of water molecules. Increasing the temperature or adding electrolytes in the smectite particles have accelerated the CO2 hydrate dissociation. Overall, the nucleation and dissociation mechanisms of CO2 hydrate in the linked inter- and intra-particle pores of dioctahedral smectite particles not only substantially affects the carbon storage and methane extraction in hydrate reservoirs, but also have potentially important impacts on pore fluids transportation in marine sediments.

Mechanisms, Growth Rates, and Morphologies of Gas Hydrates of Carbon Dioxide, Methane, and Their Mixtures

Mechanisms of growth and dissociation, growth rates, and morphology of gas hydrates of methane, carbon dioxide, and two CH4:CO2 mixtures (80:20 and 30:70 nominal concentration) were studied using using high resolution images and very precise temperature control. Subcooling and a recently proposed mass transfer-based driving force were used to analyze the results. When crystal growth rates did not exceed 0.01 mm/s, all systems showed faceted, euhedral crystal habits at low driving forces. At higher driving forces and growth rates, morphologies were different for all systems. These results solve apparent contradictions in literature about the morphology of hydrates of methane, carbon dioxide, and their mixtures. Differences in the growth mechanism of methane-rich and carbon dioxide-rich hydrates were elucidated. It was also shown that hydrate growth of methane, carbon dioxide, and their mixtures proceed via partial dissociation of the growing crystal. Temperature gradients were used to dissociate hydrates at specific locations, which revealed a most interesting phenomenon: On dissociation, carbon dioxide-rich hydrates propagated onto the bare substrate while drawing water from the opposite side of the sample. Furthermore, it was shown that an abrupt change in morphology common to all systems could be correlated to a change in the slope of growth rate data. This change in morphology was explained by a shift in the crystal growth mechanism.

Dynamic viscosity of methane and carbon dioxide hydrate systems from pure water at high-pressure driving forces

The viscosity of methane and carbon dioxide hydrate systems were measured using a high-pressure rheometer up to 30 MPag. Where hydrate formation was not detected, the effect of temperature on the viscosity was one order of magnitude higher than the pressure effect on viscosity in most of the experimental pressure range (-0.048 mPa∙s/℃ at 1 MPag and 0.009 mPa∙s/MPag at 2℃). The pressure effect on the viscosity of carbon dioxide systems where no hydrate formation was observed was up to one order of magnitude higher than that of the methane systems, due to carbon dioxide’s higher solubility in water. Novel rheological phases diagrams were developed to further characterize the gas hydrate systems. Several systems with high driving forces for hydrate formation (2.07 MPag to 4.1 MPag) did not form gas hydrates. System limitations to the formation of hydrates were categorized as kinetic, mass diffusion, and/or heat of crystallization effects.

Thermodynamic analysis and economic assessment of a carbon dioxide hydrate-based vapor compression refrigeration system using load shifting controls in summer

The present work proposed a novel two-stage carbon dioxide hydrate-based vapor-compression refrigeration system. The proposed system applied pure carbon dioxide hydrate as the primary refrigerant and arranged both of hydrate formation and dissociation at the low-pressure stage. The thermodynamic and economic models were developed and then performances of the proposed system using load-levelling storage and full storage operations were evaluated and compared with those of a conventional carbon dioxide single-stage vapor-compression refrigeration system, which is treated as the baseline and with no energy storage. The simulation results indicate that the design capacity of the proposed system using full storage is the largest among the three systems, but with lowest operation cost, and with the incentivization of electricity prices ratio of on and off-peak this cost savings would raise significantly. Noted that the bill structure reveals the load-levelling storage system saves most on the water consumption. Due to the dominant expenditure on the two compressors, compare with the baseline system, the initial capital cost of the full storage system was 75.5% higher, whereas that of the levelling-load storage system was only 21.5% higher. Finally, this paper discussed the economic feasibility on the initial capital cost for the proposed system and developed an indication map to predict the profit years in case of that the new system using load-levelling storage operation replaces the baseline system assuming a system lifetime of 15 years under different electricity prices ratios.

Kinetic Inhibition of CO2 Hydrate by Carboxymethylcellulose Sodium through Retarded Mass Transfer

The influence of carboxymethylcellulose sodium (CMC-Na) on the formation kinetics of carbon dioxide (CO2) hydrate was investigated by adopting an isothermal and isochoric method. The mass transfer ...

Application of Gaussian Process Regression (GPR) in Gas Hydrate Mitigation

The production of oil and natural gas contributes to a significant amount of revenue generation in Malaysia thereby strengthening the country’s economy. The flow assurance industry is faced with impediments during smooth operation of the transmission pipeline in which gas hydrate formation is the most important. It affects the normal operation of the pipeline by plugging it. Under high pressure and low temperature conditions, gas hydrate is a crystalline structure consisting of a network of hydrogen bonds between host molecules of water and guest molecules of the incoming gases. Industry uses different types of chemical inhibitors in pipeline to suppress hydrate formation. To overcome this problem, machine learning algorithm has been introduced as part of risk management strategies. The objective of this paper is to utilize Machine Learning (ML) model which is Gaussian Process Regression (GPR). GPR is a new approach being applied to mitigate the growth of gas hydrate. The input parameters used are concentration and pressure of Carbon Dioxide (CO2) and Methane (CH4) gas hydrates whereas the output parameter is the Average Depression Temperature (ADT). The values for the parameter are taken from available data sets that enable GPR to predict the results accurately in terms of Coefficient of Determination, R2 and Mean Squared Error, MSE. The outcome from the research showed that GPR model provided with highest R2 value for training and testing data of 97.25% and 96.71%, respectively. MSE value for GPR was also found to be lowest for training and testing data of 0.019 and 0.023, respectively.

Application of Bacillus mucilaginosus in the carbonation of steel slag.

The stacking of steel slag has detrimental effects mainly for the waste of resources and the pollution of environment. In this study, a novel method based on microbially induced calcium precipitation (MICP) was proposed by utilizing a type of microorganism named Bacillus mucilaginosus, which could secrete carbonic anhydrase (CA) through the metabolism process, accelerating the hydration of carbon dioxide (CO2) and thus facilitating the formation of carbonate ions (CO32-). First, comparing the biologically deposited calcium carbonate with the chemically deposited one, it was found that the crystallinity and crystal size of the biological deposition was lower, leading to its cementitious properties. Under the condition of 1 wt. (weight) % dosage, the carbonation degree increased from 66.34 to 86.25% and the compressive strength improved greatly from 7.4 to 11.2MPa as well. The weight gain rate of biologically carbonated specimens was also twice as much as the directly carbonated ones. This work strongly demonstrated that biological carbonation technology could not only improve the CO2 sequestration potential of steel slag but also enhance the mechanical properties and durability of steel slag products. KEY POINTS: • Bacillus mucilaginosus could resuscitate and proliferate in the steel slag environment. • B. mucilaginosus secreted carbon anhydrase, which could accelerate the hydration of CO2 and facilitate the precipitation of calcium carbonate. • Biologically carbonated steel slag had greater mechanical performance than directly carbonated one.

In situ experimental study on the effect of mixed inhibitors on the phase equilibrium of carbon dioxide hydrate

Electrolytes and alcohols are two thermodynamic inhibitors commonly used to prevent hydrate growth in gas and oil pipelines in the gas industry. Although the phase behavior of CO2 hydrate in the presence of electrolyte and/or alcohol has been extensively studied, the knowledge of the combined effect of these two as mixed inhibitors on CO2 hydrate is still very limited. In this study, the influence of mixed inhibitors comprising an electrolyte (selected from sodium chloride and calcium chloride) mixed with an alcohol (selected from methanol, ethanol, ethylene glycol, n-propanol, and isopropanol) on the thermodynamic properties of carbon dioxide hydrate was investigated. Observations on CO2-H2O-NaCl-alcohol system were performed using high-pressure optical cell (HPOC) technology. The experiments were carried out at low temperatures of 263–283 K and high pressures up to 4 MPa, focusing on the phase equilibrium of liquid, hydrate, and carbon dioxide gas in HPOC. Experimental results reveal that the inhibition strength of the mixed inhibitor is clearly enhanced; in some cases, the inhibition intensity of the mixed inhibitor is greater than the sum of its components because of the synergistic effect. For example, under a pressure of ∼ 2 MPa, the temperature depressions of 10 wt% methanol and 10 wt% sodium chloride for CO2 hydrate are 4.53 K and 4.87 K, respectively; the mixture of these two can produce a temperature depression as high as 12.53 K. Our results also show that the inhibition strength of the inhibitor, single or mixed, increases with the pressure. Based on our results, an improved van der Waals Platteeuw (vdWP) model is proposed to predict the hydrate stability conditions in the CO2-H2O-inhibitor solution. Results from this study provide a ground for a better understanding of the thermodynamic properties of carbon dioxide hydrate under extreme conditions.

Electrocatalysis of CO2 and CH4 Hydrates at Subzero Temperatures

So far electrocatalytic process in aqueous solution have been extensively studied as a function of the temperature in the range 0 and 99 °C but very little is known about electrocatalytic processes at temperatures below the freezing point. In electrochemistry at low temperatures, the reactions associated with water splitting might be suppressed due to the formation of ice-like structure at the interface, while the stabilization of other reaction species can be stabilized resulting in changes to the kinetics of the reactions studied.1-3 In addition, decreasing the temperature of water to subfreezing temperatures would significantly increase the solubility of some gases in water thus affecting the reaction rate and reaction mechanism of the electrochemical reactions. By taking advantage of the high solubility of the carbon monoxide and methane at low temperature, achievable in brines, we report the electrochemical conversion of these gases in aqueous media down to −40 °C. We will report the electrochemical conversion of CO2 at low temperatures and demonstrate, unexpectedly, that its reduction in these conditions follows an anti-Arrhenius kinetics electrochemical environment. We will also show that electrochemical oxidation of CH4 is feasible at subzero temperatures due to the 5-fold increase in the concentration of CH4 and the formation of in gas hydrate slurries. These findings open windows of investigation into electrocatalysis in brines below the freezing point of water.Gas hydrates or clathrates are a crystalline solid formed of water and gas. Clathrates looks and acts much like ice, but it contains large amounts of gas trapped within a crystal structure of water. Gas hydrates such as hydrates of hydrocarbons, sulfur dioxide (SO2) and carbon dioxide (CO2) have been reported but they are only used for academic purposes with just a very few examples which have reached technical application. However, gas hydrates might have play an important role in the origin of life, and the chemistry on gas hydrates is relevant in energy applications in particular for space exploration.We will show the electrochemical behavior of hydrogen and oxygen adsorption and desorption processes on different metal electrodes in aqueous brines at subfreezing temperatures. Finally, we will report the first electrochemical results of the CO2RR and the oxidation of CH4 in aqueous brines at subfreezing temperatures down to -40°C.4 Our results will be explained on the basis of the presence of ice-structure clathrates,5,6 solubility of the gases as a function of temperature, kinematic viscosity, mass transport and the changes in the pH of the solution.7,8 The understanding of the electrochemistry of gas hydrates at low temperature is paramount for the development of sustainable energy cycle based on CH4 and CO2 reversible fuel cells under severe environmental conditions. This will be critical to ensure the availability of key in situ resources sustaining future human exploration and colonization of other planets.