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• The dodecahedral-cage deformation effect on hydrate formation was first modeled. • The effects of multiple solutes on hydrate formation were first modeled. • The gas dissolution effect on hydrate formation was discussed. • The saturation effect of TBAB concentration on hydrate formation was found. • The hydrate formation pressure is accurately predicted by this model. The accurate prediction of thermodynamic equilibrium hydrate formation pressure (P eq) is crucial to the industrial application of hydrate-based gas separation. This study evaluated P eq of CH 4 -CO 2 gas mixtures with different TBAB solutions at different temperatures. Unlike previously reported models, the proposed model accounted for the effects of interaction of multiple solutes and the deformation of dodecahedral (D)-cages on P eq , thereby minimizing deviations in predictions. The effects of the interaction of multiple solutes on P eq can be attributed to gas dissolution and the presence of electrolytes. For accurate prediction, the proposed model incorporated the aforementioned effects based on the electrolyte-cubic plus association equation of state and the parameters for interaction among guest molecules in cages Furthermore, the proposed model can quantitatively describe the effects of gas dissolution, the presence of electrolytes and deformation of D-cages on the P eq values for corresponding systems. [ABSTRACT FROM AUTHOR]

Hydrate-based gas separation (HBGS) needs a kinetic promoter to increase its economic value. The kinetic promoters for HBGS should have low foaming ability, high performance on increasing the conversion rate of the water into hydrate (R WH) and little thermodynamic inhibition on hydrate formation. However, no reported kinetic promoter meets all above requirements at same time. According to the experimental results in this work, n-octyl-β- d -glucopyranoside (OGP) met all those requirements of HBGS. For that reason, OGP was proposed as a new kinetic promoter for HBGS, and its effects on HBGS were revealed by investigating the HBGS of hydrogen and ethylene from fluid catalytic cracking dry gas in presence of OGP in this work. OGP enhanced the HBGS performance by increasing R WH from less than 64% to higher than 84%. By one-step separation, the hydrogen concentration was increased from 26.0 mol% to about 46.8 mol% while the ethylene concentration was increased from 52.0 mol% to about 74.4 mol%. The effect of the initial OGP concentration in liquid phase (w p,0) on HBGS increased with the increase in R WH , and the optimum w p,0 was 0.20 mass%. The processing capacity of the OGP solution in the HBGS was about 350 NL feed gas/L. OGP enhanced the promotion of increasing pressure on the HBGS performance. A new model was proposed to predict the thermodynamic equilibrium hydrate formation pressures of the experimental systems: the maximum relative deviation is 5.08% and the average relative deviation is 2.61%. [Display omitted] • OGP increased R WH from less than 64% to higher than 84%. • The hydrogen concentration was increased from 26.0 mol% to about 46.8 mol%. • The ethylene concentration was increased from 52.0 mol% to about 74.4 mol%. • The processing capacity of the OGP solution in the HBGS was 350 NL feed gas/L. • A new model was proposed to quantitatively analyze the effect of OGP on HBGS. [ABSTRACT FROM AUTHOR]

A pressure swing hydrate-membrane coupled separation (PSHMS) process was designed, and process simulation was conducted using a combination of Aspen Plus and Excel. PSHMS achieves continuous, highly efficient, and stable production of qualified gaseous products without thermodynamic promoters of hydrate or circulating working fluids. In hydrogen separation from diesel hydrogenation tail gas, PSHMS exhibits lower energy consumption and higher efficiency compared to hydrate-based separation technologies. Sensitivity analyses of various design parameters within PSHMS were performed through simulation, the results indicate that low temperature, high initial pressure, and high water content are all advantageous for improving separation efficiency. The selection of feed rates needs to be determined comprehensively based on the design parameters. The optimized unit energy consumption of PSHMS is merely 46.41 kJ/mol, significantly lower than the 117.94 kJ/mol of hydrate-based separation technology. • Study of self-designed pressure swing hydrate-membrane coupled method (PSHMS). • The energy consumption of PSHMS is only 40% of that in hydrate-based separation method. • The operational approach of pressure swing separation mitigates hydrate blockage issues in pipelines. • Sensitivity analysis of design parameters in PSHMS was conducted. • Lower temperatures, higher pressures, and increased water content are conducive to effective performance. [ABSTRACT FROM AUTHOR]

• A novel hydrate-based gas separation model, namely the gas–water-hydrate three-phase flash model, was proposed. • The proposed model further considers the structural transitions of hydrates. • Four typical hydrate structure transformations are discussed through experiments. • The key parameters for calculating the degree of hydrate structural transitions were optimized. • The calculation results of the proposed model have an absolute average relative deviation of 8.00%. The study introduces a pioneering model for hydrate-based gas separation technology, which enhances the prediction method for the coexistence of multiple structure hydrates. The calculated results demonstrate strong agreement with 96 sets of experimental data, exhibiting a lower average relative deviation of 8.00 % compared to the traditional model's average relative deviation of 60.00 %. Furthermore, it offers a comprehensive discussion on the composition of hydrate structures in (H 2 + CH 4 + C 2 H 6 + C 3 H 8) during gas–water-hydrate equilibrium, providing a more precise depiction of hydrate structure evolution. Additional gas-hydrate equilibrium experiments were conducted for the (H 2 + CH 4 + C 2 H 6 + C 3 H 8) system to optimize the model parameters. The fitting goodness of the hydrate structure transformation formula (n i I - S i formula) is enhanced from 0.9162 to 0.9816. [ABSTRACT FROM AUTHOR]

• The increase in R WH affects the effects of w p,0 , IFL and temperature on separation. • PSS enhances the performance of the separation with high R WH. • The maximum processing capacity of the separation is 300 NL feed gas/L solution. • The effect of decreasing temperature on separation decreases as R WH increases. • A model was proposed to predict the equilibrium hydrate formation pressure. The effects of the influential factors (initial promoter concentration in liquid phase, initial ratio of the volumes of gas to liquid (IFL) and temperature) on the hydrate-based gas separation (HBGS) and their relationships with the conversion rate of the water into hydrate (R HW) were experimentally investigated. Poly (sodium 4-styrenesulfonate) (PSS) was first-time used in HBGS. After one-stage HBGS, hydrogen can be concentrated from 26.0 mol% to more than 45.9 mol% in the residual gas and ethylene can be concentrated from 52.0 mol% to more than 72.6 mol% in the dissociated gas. PSS had low foaming ability, it effectively decreased the gas–liquid interfacial tension and had little effect on the thermodynamic equilibrium hydrate formation condition. PSS had little effect on the separation performance when R HW was about 13% whereas it significantly improved the separation performance when R HW was higher than 59%, the optimum PSS concentration was 0.2 mass%. In the separation in presence of PSS, the increase in IFL did not cause a decrease in the separation performance until IFL increased to more than 300 NL/L. The positive effect of decreasing temperature on HBGS decreased with the increase in R HW , and it disappeared in the HBGS using pure water when R HW was higher than 57.0% whereas it still existed in the HBGS using PSS solution when R HW was 67.8%. An innovative model was established to predict the equilibrium hydrate formation pressure, and the average relative deviation was 2.6%, with the maximum relative deviation being 5.5%. [ABSTRACT FROM AUTHOR]

• Enterococcus faecium C171 strain modulates acute immune response against lethal viral challenge. • E. faecium C171 has anti-inflammatory and anti-infective effects. • Bacterial extracellular vesicles (Efm-C171-BEVs) isolated from E. faecium C171. • Anti-inflammatory properties of E. faecium C171 not due to Efm-C171-BEVs. • E. faecium C171 and Efm-C171-BEVs potential therapeutic agents for acute inflammatory diseases. Commensal bacteria modulate acute immune responses to infection in hosts. In this study, Enterococcus faecium C171 was screened and isolated. This strain has similar basic characteristics to the reference probiotic, including strong anti-inflammatory and anti-infective effects. E. faecium C171 inhibits the production of pro-Caspase-1 and significantly reduces the production of interleukin-1β (IL-1β) in vitro. These reactions were confirmed using the Transwell system. Live E. faecium C171 mainly exerted an inhibitory effect on acute inflammation, whereas the anti-infective and immune-activating effects were primarily mediated by the E. faecium C171-produced bacterial extracellular vesicles (Efm-C171-BEVs). Furthermore, in the specific pathogen-free (SPF) chicken model, oral administration of E. faecium C171 increased the relative abundance of beneficial microbiota (Enterococcus and Lactobacillus), particularly Enterococcus , the most important functional bacteria of the gut microbiota. E. faecium C171 significantly inhibited the acute inflammatory response induced by a highly virulent infectious disease, and reduced mortality in SPF chickens by 75%. In addition, E. faecium C171 induced high levels of CD3+ , CD4-, and CD8- immunoregulatory cells and CD8+ killer T cells, and significantly improved the proliferative activity of T cells in peripheral blood mononuclear cells, and the secretion of interferon-γ. These findings indicate that E. faecium C171 and Efm-C171-BEVs are promising candidates for adjuvant treatment of acute inflammatory diseases and acute viral infections. [ABSTRACT FROM AUTHOR]