The stability of ionic liquid additive 1-butyl-3-methylimidazolium hydrogen sulfate （[BMIM]HSO4） during zinc electrowinning from acidic sulfate solution was investigated by cyclic voltammetry, electrochemical impeda...The stability of ionic liquid additive 1-butyl-3-methylimidazolium hydrogen sulfate （[BMIM]HSO4） during zinc electrowinning from acidic sulfate solution was investigated by cyclic voltammetry, electrochemical impedance spectroscopy and scanning electron microscopy. Compared with the traditional industrial additives, gelatine and gum arabic, [BMIM]HSO4 has more excellent chemical and thermal stabilities. The inhibition effects of gelatine and gum arabic on the zinc electrocrystallization are observed to markedly weaken due to their part degradation after 12 h longtime successive electrolysis and high temperature （90 ℃） treatments. In contrast, the activity of [BMIM]HSO4 is practically unaffected after 24 h longtime successive electrolysis and high temperature treatments. These results are corroborated with the corresponding morphological analysis of the cathodic deposits.展开更多
A dabco-based basic ionic liquid,1-butyl-4-aza-1-azaniabicyclo[2.2.2]octane hydroxide,has been developed as a catalyst for a convenient and rapid method for the Michael addition of active methylene compounds to a b-un...A dabco-based basic ionic liquid,1-butyl-4-aza-1-azaniabicyclo[2.2.2]octane hydroxide,has been developed as a catalyst for a convenient and rapid method for the Michael addition of active methylene compounds to a b-unsaturated carboxylic esters and nitriles.The method is very simple,and the yields are very high.The catalyst can be recycled several times without much loss of activity.展开更多
基金Project(2011FA009) supported by the Natural Science Foundation of Yunnan Province,ChinaProject(2011FZ020) supported by the Application Foundation Research of Yunnan Province,China
文摘The stability of ionic liquid additive 1-butyl-3-methylimidazolium hydrogen sulfate （[BMIM]HSO4） during zinc electrowinning from acidic sulfate solution was investigated by cyclic voltammetry, electrochemical impedance spectroscopy and scanning electron microscopy. Compared with the traditional industrial additives, gelatine and gum arabic, [BMIM]HSO4 has more excellent chemical and thermal stabilities. The inhibition effects of gelatine and gum arabic on the zinc electrocrystallization are observed to markedly weaken due to their part degradation after 12 h longtime successive electrolysis and high temperature （90 ℃） treatments. In contrast, the activity of [BMIM]HSO4 is practically unaffected after 24 h longtime successive electrolysis and high temperature treatments. These results are corroborated with the corresponding morphological analysis of the cathodic deposits.
文摘A dabco-based basic ionic liquid,1-butyl-4-aza-1-azaniabicyclo[2.2.2]octane hydroxide,has been developed as a catalyst for a convenient and rapid method for the Michael addition of active methylene compounds to a b-unsaturated carboxylic esters and nitriles.The method is very simple,and the yields are very high.The catalyst can be recycled several times without much loss of activity.
