Separation of products from ionic liquid(IL) solvents is one of the main challenges that hinder their utilizations. In this study, the production of γ-valerolactone(GVL) by selective hydrogenation of α-angelica lact...Separation of products from ionic liquid(IL) solvents is one of the main challenges that hinder their utilizations. In this study, the production of γ-valerolactone(GVL) by selective hydrogenation of α-angelica lactone(AL) and separation of the products from the IL solvent were carried out by using subcritical CO_2 as a "switch" at room temperature. After the mixture was separated into two phases by subcritical CO_2, AL and nano Pd/C catalyst were only found in the lower IL-rich phase, GVL was produced with quantitative yield and enriched in the upper methanolrich phase. Pure GVL can be obtained by depressurizing to release CO_2 and evaporation to remove methanol of the upper phase, the lower phase containing IL, catalyst and methanol can be recycled for the next reaction. The strategy may provide a new approach to produce and separate products from IL solvents at mild conditions.展开更多
为深入研究柔性导爆索在爆炸分离装置中的作用过程和机理,提出一种改进的光滑粒子流体动力学方法(smoothed particle hydrodynamics,SPH)与有限单元法(finite element method,FEM)耦合算法。新方法中不仅包含导爆索模拟的SPH方法与分离...为深入研究柔性导爆索在爆炸分离装置中的作用过程和机理,提出一种改进的光滑粒子流体动力学方法(smoothed particle hydrodynamics,SPH)与有限单元法(finite element method,FEM)耦合算法。新方法中不仅包含导爆索模拟的SPH方法与分离装置模拟的FEM方法之间的接触算法,同时将完全损伤失效后的单元采用转化算法动态转化成SPH粒子继续参与计算,转化后的粒子与未转化的有限单元之间采用接触算法计算。采用该方法对环型和平板型两种爆炸分离结构的分离过程进行了数值模拟,验证了新方法的准确性与问题适用性;分析了分离板的变形断裂及损伤碎片的飞溅过程,得到了分离装置表面不同时刻的应力分布、损伤因子的变化趋势、von Mises应力的变化趋势;探讨了炸药在不同比内能情况下单元的屈服损伤速度、碎片的飞溅位移速度。展开更多
基金supported by International S&T Cooperation Program of China(2014DFA61670)External Cooperation Program of BIC,Chinese Academy of Sciences(GJHZ201306)National Natural Science Foundation of China(No.21276260,21576269,21476245,21406230)
文摘Separation of products from ionic liquid(IL) solvents is one of the main challenges that hinder their utilizations. In this study, the production of γ-valerolactone(GVL) by selective hydrogenation of α-angelica lactone(AL) and separation of the products from the IL solvent were carried out by using subcritical CO_2 as a "switch" at room temperature. After the mixture was separated into two phases by subcritical CO_2, AL and nano Pd/C catalyst were only found in the lower IL-rich phase, GVL was produced with quantitative yield and enriched in the upper methanolrich phase. Pure GVL can be obtained by depressurizing to release CO_2 and evaporation to remove methanol of the upper phase, the lower phase containing IL, catalyst and methanol can be recycled for the next reaction. The strategy may provide a new approach to produce and separate products from IL solvents at mild conditions.