在1-丁基-3-甲基咪唑硫酸氢盐([BMIM]HSO4)电镀液中,探究了18-冠醚-6添加剂对电沉积铬的影响.紫外-可见光谱结果表明,18-冠醚-6与Cr^(3+)形成配合物,使最大吸收波长发生红移.循环伏安研究表明,Cr^(3+)的还原经历了两步.18-冠醚-6的添加...在1-丁基-3-甲基咪唑硫酸氢盐([BMIM]HSO4)电镀液中,探究了18-冠醚-6添加剂对电沉积铬的影响.紫外-可见光谱结果表明,18-冠醚-6与Cr^(3+)形成配合物,使最大吸收波长发生红移.循环伏安研究表明,Cr^(3+)的还原经历了两步.18-冠醚-6的添加使Cr^(3+)的峰电位和起始还原电位均正移了220 m V.能谱仪(EDS)结果显示,在18-冠醚-6的作用下镀层中铬含量有所提高.铬镀层的扫描电子显微镜(SEM)表征结果表明,加入18-冠醚-6后,所得镀层的颗粒变大.18-Crown-6/CrCl3/[BMIM]HSO4/H2O电镀液中工艺优化的结果为:在温度为50℃、pH值为3.5、电流密度为1200 A·m^(-2)、电镀时间为1.5 h的最佳工艺条件下,铬镀层的厚度达到72.5μm,电流效率为42.3%.展开更多
The effects of N-methylimidazole cation [Cnmim] with different alkyl chain lengths, the types of cations and anions of ionic liquids and the reaction parameters on the catalytic activity and the selectivity for 4,4′-...The effects of N-methylimidazole cation [Cnmim] with different alkyl chain lengths, the types of cations and anions of ionic liquids and the reaction parameters on the catalytic activity and the selectivity for 4,4′-bisphenol F were investigated. The hydrogen bonding between the hydroxyl of phenol and the C2-position hydrogen of imidazole moiety in hydrophilic imidazole-based ionic liquid has important influence on the selectivity for 4,4′-bisphenol F, and under the conditions of the molar ratio of phenol/[C4mim][HSO4] 1:1, reaction temperature65 °C and the theoretical molar ratio of phenol/formaldehyde 2:1, the selectivity for 4,4′-bisphenol F reached69.1%. Compared with the high phenol/formaldehyde ratio reported in literatures, the low molar ratio of phenol/formaldehyde and the low reaction temperature can greatly reduce energy consumption, and has important significance for industrial application.展开更多
文摘在1-丁基-3-甲基咪唑硫酸氢盐([BMIM]HSO4)电镀液中,探究了18-冠醚-6添加剂对电沉积铬的影响.紫外-可见光谱结果表明,18-冠醚-6与Cr^(3+)形成配合物,使最大吸收波长发生红移.循环伏安研究表明,Cr^(3+)的还原经历了两步.18-冠醚-6的添加使Cr^(3+)的峰电位和起始还原电位均正移了220 m V.能谱仪(EDS)结果显示,在18-冠醚-6的作用下镀层中铬含量有所提高.铬镀层的扫描电子显微镜(SEM)表征结果表明,加入18-冠醚-6后,所得镀层的颗粒变大.18-Crown-6/CrCl3/[BMIM]HSO4/H2O电镀液中工艺优化的结果为:在温度为50℃、pH值为3.5、电流密度为1200 A·m^(-2)、电镀时间为1.5 h的最佳工艺条件下,铬镀层的厚度达到72.5μm,电流效率为42.3%.
基金Supported by the National Natural Science Foundation of China(21276217)
文摘The effects of N-methylimidazole cation [Cnmim] with different alkyl chain lengths, the types of cations and anions of ionic liquids and the reaction parameters on the catalytic activity and the selectivity for 4,4′-bisphenol F were investigated. The hydrogen bonding between the hydroxyl of phenol and the C2-position hydrogen of imidazole moiety in hydrophilic imidazole-based ionic liquid has important influence on the selectivity for 4,4′-bisphenol F, and under the conditions of the molar ratio of phenol/[C4mim][HSO4] 1:1, reaction temperature65 °C and the theoretical molar ratio of phenol/formaldehyde 2:1, the selectivity for 4,4′-bisphenol F reached69.1%. Compared with the high phenol/formaldehyde ratio reported in literatures, the low molar ratio of phenol/formaldehyde and the low reaction temperature can greatly reduce energy consumption, and has important significance for industrial application.
