The separation between methane and nitrogen is an inevitable and important task in the C1 chemicaltechnology and the utilization of methane from coalbed, yet it is considered to be one of the tough tasks in thefield o...The separation between methane and nitrogen is an inevitable and important task in the C1 chemicaltechnology and the utilization of methane from coalbed, yet it is considered to be one of the tough tasks in thefield of separation. Pressure swing adsorption is a preferable technology if an adsorbent that allowing a largecoefficient of separation for the CH4/N2 system is available. The separation coefficients between CH4 and N2were obtained on analyzing the breakthrough curves measured experimentally with nine adsorbents. A technique ofmeasuring the temperature-pulse was incorporated in the experiments, and the reliability of the result was improved.Superactivated carbon with large surface area and plenty of micropores was shown to have the largest separationcoefficient and to be promising for the commercial utilization.展开更多
Recently, the electrochemical N2 reduction reaction （NRR） in aqueous electrolytes at ambient temperature and pressure has demonstrated its unique advantages and potentials. The reactants are directly derived from ga...Recently, the electrochemical N2 reduction reaction （NRR） in aqueous electrolytes at ambient temperature and pressure has demonstrated its unique advantages and potentials. The reactants are directly derived from gaseous N2 and water, which are naturally abundant, and NH3 production is important for fertilizers and other industrial applications. To improve the conversion yield and selectivity （mainly competing with water reduction）, electrocatalysts must be rationally designed to optimize the mass transport, chemisorption, and transduction pathways of protons and electrons. In this review, we summarize recent progress in the electrochemical NRR. Studies of electrocatalyst designs are summarized for different categories, including metal-based catalysts, metal oxide-derived catalysts, and hybrid catalysts. Strategies for enhancing the NRR performance based on the facet orientation, metal oxide interface, crystallinity, and nitrogen vacancies are presented. Additional system designs, such as lithium-nitrogen batteries, and the solvent effect are introduced. Finally, existing challenges and prospects are discussed.展开更多
文摘The separation between methane and nitrogen is an inevitable and important task in the C1 chemicaltechnology and the utilization of methane from coalbed, yet it is considered to be one of the tough tasks in thefield of separation. Pressure swing adsorption is a preferable technology if an adsorbent that allowing a largecoefficient of separation for the CH4/N2 system is available. The separation coefficients between CH4 and N2were obtained on analyzing the breakthrough curves measured experimentally with nine adsorbents. A technique ofmeasuring the temperature-pulse was incorporated in the experiments, and the reliability of the result was improved.Superactivated carbon with large surface area and plenty of micropores was shown to have the largest separationcoefficient and to be promising for the commercial utilization.
文摘Recently, the electrochemical N2 reduction reaction （NRR） in aqueous electrolytes at ambient temperature and pressure has demonstrated its unique advantages and potentials. The reactants are directly derived from gaseous N2 and water, which are naturally abundant, and NH3 production is important for fertilizers and other industrial applications. To improve the conversion yield and selectivity （mainly competing with water reduction）, electrocatalysts must be rationally designed to optimize the mass transport, chemisorption, and transduction pathways of protons and electrons. In this review, we summarize recent progress in the electrochemical NRR. Studies of electrocatalyst designs are summarized for different categories, including metal-based catalysts, metal oxide-derived catalysts, and hybrid catalysts. Strategies for enhancing the NRR performance based on the facet orientation, metal oxide interface, crystallinity, and nitrogen vacancies are presented. Additional system designs, such as lithium-nitrogen batteries, and the solvent effect are introduced. Finally, existing challenges and prospects are discussed.
