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This work aims at reporting the dissociationpressures of carbondioxide simple hydrates in the aqueous solution of N-butyl-N-methylpyrrolidinium bromide at four differentmass fractions (0.01, 0.05, 0.10, and 0.20) in the pressure rangeof (2.34 to 3.13) MPa and in the temperature range of (276.63 to 280.63)K, respectively. The experiment was carried out by employing an isochoricpressure-search method. The obtained CO2hydrate equilibriumdata in pure water were compared with those from literatures, andthe good agreement demonstrated the good reliability and accuracyof our experimental apparatus and method. The equilibrium data measuredwith the addition of N-butyl-N-methylpyrrolidiniumbromide showed that it acted as a thermodynamic inhibitor to changethe hydrate stable region to lower temperature or higher pressures.Also, with the mass fraction increasing, the inhibition effect becamestronger. However, it was a weak thermodynamic inhibitor comparedwith some conventional ones. [ABSTRACT FROM AUTHOR]

This work aims to report the cyclopentane(CP)-carbon dioxide binary sII hydrate phase equilibrium data in the presence of aqueous sodium chloride solutions at five different mass fractions (0.00, 0.035, 0.07, 0.10, 0.15 and 0.25) in the range of temperature from (269.8 to 292.4) K and pressure from (1.18 to 3.33) MPa. An isochoric pressure-search method is applied for the experimental measurements. The obtained equilibrium data of CO2 hydrate in pure water are compared with those from the literature. The good agreement validates that our experimental apparatus and approach are well-established and reliable. It is indicated that the inhibiting effect of NaCl yields to the promotion effect of cyclopentane except for the case of 0.25 mass fraction of aqueous NaCl solution. [ABSTRACT FROM AUTHOR]

In this work, the phase equilibrium data of methane hydrate in tetrahydrofuran (THF) and tetra-n-butylammonium chloride (TBAC) mixed aqueous solutions were investigated in the temperature range of (279.6 to 301.5) K and pressure range of (3.74 to 11.62) MPa. The measurements were carried out at mass fraction of 0.019 THF with the mass fraction of 0.020, 0.050, 0.101, 0.201, and 0.340 TBAC, and 0.058 THF with 0.102, 0.202, and 0.340 TBAC. The phase equilibrium data were obtained by the isochoric pressure-search method. The results showed that the addition of THF + TBAC could remarkably increase the phase equilibrium temperatures compared to the equilibrium temperature of pure CH4 hydrate. However, the addition of THF + TBAC mixtures did not push the CH4 hydrates equilibrium temperature to a higher degree compared to the addition of single THF. In stabilizing hydrate crystals, the TBAC played a positive role when the concentration of THF was low, but a negative role when the concentration of THF became high. [ABSTRACT FROM AUTHOR]

A feasible and scalable two-step method is developed to synthesize LiFeSO4Fy(OH)1-y which could deliver 92 and 80 mA h g-1 when cycled at 1 C and 15 C, respectively. Moreover, with 80% of capacity retention after 2800 cycles at 1 C, this material should be of great interest as a contender to LiFePO4 for use in high power Li-ion batteries. [ABSTRACT FROM AUTHOR]