关键词: 偏摩尔体积, 氮气, 氢气, 氨气, 超临界, 介质, 氨合成

Abstract: The partial molar volumes of components in a supercritical ammonia synthesis system were calculated under different conditions with the calculation formula of partial molar volume derived from R-K equation of state.The objectives were to comprehend phase behavior of components and to provide the theoretical explanation and guidance for developing novel processes of ammonia synthesis under supercritical conditions. The conditions of calculation were H₂/N₂=3, concentration of NH₃ in synthesis gas ranging from 2% to 15%, concentration of medium in supercritical ammonia synthesis system ranging from 20% to 50%,temperature ranging from 243 K to 699 K and pressure ranging from 0.1 MPa to 187 MPa.The results showed that the ammonia synthesis system could reach supercritical state by adding a suitable supercritical medium and then controlling the reaction conditions.It was good for supercritical ammonia synthesis that medium reached supercritical state under the corresponding total pressure and composition,and at a temperature near the normal temperature or near the critical temperature of medium or in the range of temperature of commercial ammonia synthesis.

Key words: 偏摩尔体积, 氮气, 氢气, 氨气, 超临界, 介质, 氨合成