【摘要】 本文采用上升液滴法,研究了氯化铀酰在盐酸介质和磷酸三丁酯（TBP）之间的传质过程.在一定浓度的盐酸溶液中,TBP 萃取铀的速率与[U]和[TBP]₀²成正比;反萃速率与[U]₀成正比,而与[TBP]₀成反比.在温度为20～40℃范围内分别测定了萃取和反萃反应的活化能,它们的差值与由萃取平衡分配比与温度关系测得的焓变相符.可以认为,萃合物 UO₂Cl₂·2TBP 的生成和离解都是分步进行的,中间产物是 UO₂Cl₂·TBP;萃取速率的控制步骤是 UO₂Cl₂·2TBP 的生成反应,而反萃速率的控制步骤是 UO₂Cl₂·TBP 的离解反应.更多还原

【Abstract】 The rate of forward and backward extraction of uranium（VI）between aqueoushydrochloric acid solution and tri-n-butyl phosphate（TBP）in cyclohexane has beenmeasured using the single drop technique.It have been found that the rate of forwardextraction is proportional to[U]and[TBP]_（0）² while that of backward extraction to[U]_（0）and[TBP]_（0）^-1.The apparent activation energies were found to be 7.8 kcal/molfor forward extraction and 13.8 kcal/mol for backward extraction over the temperaturerange of 20 to 40℃.The enthalpy was calculated to be -6.0 kcal/mol by the differenceof these activation energy values.It is suggested that the rate-controlling step may bethe formation of complex UO₂Cl₂·2TBP for forward extraction and the dissociation ofUO₂Cl₂·TBP for backward extraction.更多还原