期刊论文

Xia, Liang-Shu(2000000476@usc.edu.cn)

英文

化学物理学报(英文版)

1674-0068

2022

35

5

813-822

10.1063/1674-0068/cjcp2103053

supported by the National Natural Science Foundation of China （No.11575078）； Hunan Provincial Innovation Foundation for Postgraduates （CX20190713）；

本校为第一机构

The kinetics of U(IV) produced by hydrazine reduction of U(VI) with platinum as a catalyst in nitric acid media was studied to reveal the reaction mechanism and optimize the reaction process. Electron spin resonance (ESR) was used to determine the influence of nitric acid oxidation. The effects of nitric acid, hydrazine, U(VI) concentration, catalyst dosage and temperature on the reaction rate were also studied. In addition, the simulation of the reaction process was performed using density functional theory. The results show that the influence...

为明确反应机理和反应历程,优化反应工艺,本文研究了硝酸环境下Pt催化N2H4还原U（Ⅵ）制备U（Ⅳ）的反应动力学,通过电子自旋共振法确定了硝酸氧化性影响范围,研究了硝酸、肼、U（Ⅵ）浓度以及催化剂用量对反应的影响,同时利用密度泛函理论对反应过程进行了模拟.结果表明,硝酸浓度在0.5 mol/L以下氧化性对实验主反应影响有限,在0.5 mol/L浓度范围内反应动力学方程为:-dc(UO22+)/dt)=kc0.5323(UO22+)c0.2074（N2H5+）c-0.2009（H+）;当温度为50℃,催化剂固液比为r=0.0667 g/mL时,反应的动力学速率常数k为k=0.00199（mol/L）0.4712/min;在20～80℃之间,反应速率随温度的升高而逐渐增大,并由化学控...