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Four-phase (liquid water + hydrate + liquid hydrocarbon + vapor) equilibrium data are reported for structure II hydrates of methane + cyclohexane or cyclopentane and a ternary mixture gas (methane ) 91.96 mol %, ethane ) 5.13 mol %, propane ) 2.91 mol %) + cyclohexane in the pressure range (0.165 to 9.486) MPa and the temperature range (273.83 to 301.90) K. The equilibrium pressures of the experimental systems of methane + cyclohexane or cyclopentane are concededly lower than that of the system of pure methane at a given temperature. The presence of cyclohexane inhibits hydrate formation, rather than promoting it, at higher temperatures in the test system of the ternary mixture gas + cyclohexane.

The present work investigates hydrate equilibrium conditions for tetra-n-butyl ammonium bromide (TBAB) + methane + water mixtures. The experiments are carried out in the TBAB mass fraction range of (0.05 to 0.45) and in the pressure range of (0.5 to 7.0) MPa. The experimental results show that the presence of TBAB decreases the formation pressure of methane hydrate. Moreover, pressure reduction is dependent on the TBAB concentration.

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The phase equilibrium data for semiclathrate hydrates of tetra-n-butylammonium chloride (TBAC) + methane with TBAC mass fractions (w) of 0.0500, 0.0997, 0.2000, and 0.3001 are measured in the temperature range of (281.65 to 292.85) K using a visual high-pressure phase equilibrium apparatus. The experimental data are generated using an isochoric stepheating method (T-cycle method). Methane partially occupied the small cages of TBAC semiclathrate hydrates, which increases the stability of the hydrates. The phase equilibrium pressure of TBAC + methane hydrates increases with the increase of temperature at a specified TBAC concentration. The experimental results present that the presence of TBAC decreases the formation pressure of methane hydrate greatly. Moreover, pressure reduction is dependent on the TBAC concentration. The experimental data also show that TBAC is a kind of promoter for methane hydrate formation.

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Extraction of S-compounds from diesel oil by task-specific ionic liquids has been investigated. The influences of different ionic liquids, extraction time, extraction temperature, different S-compounds, the amount, and the recycling of ionic liquid were studied. This process is capable of removing up to 56% of dibenzothiophene in model diesel oil under optimum extraction conditions. At the same time, this process was applied to the real predesulfurized diesel oils. The results indicate that such a process could be an alternative to common hydrodesulfurization for deep desulfurization.

In the face of the increasingly serious greenhouse effect and climate warming, carbon dioxide reduction (CO2RR) technology, which can produce valuable chemicals and fuels while consuming CO2, has become the focus of technology development. However, in the process of CO2 conversion into high-value products, it is still a challenge for electrocatalytic materials to achieve high efficiency and selectivity while inhibiting the byproducts of the hydrogen evolution reaction. These challenges can be solved by clarifying the factors regulating the catalytic performance of the CO2RR. With this background, we divided copper-bearing catalysts into bulk phase catalyst, copper-bearing compound catalyst, alloy catalyst, and single-atom catalyst and summarized the development status of each system in recent years. In addition, we further discussed the mechanisms affecting the performance of the CO2RR to help design catalysts with more effective selectivity. We hope this Review will inspire and encourage researchers to develop copper-bearing catalysts with better CO2RR performance.