HDS废催化剂碱浸取提钒的动力学研究

Kinetics of Extracting Vanadium from HDS Spent Catalyst By Alkali Leaching

用空气焙烧 碱浸取的方法从HDS废催化剂中提取钒 ,研究了分别用Na2 CO3 H2 O、NH4HCO3 H2 O及NH3 ·H2 O浸取焙烧产物中钒的动力学规律。用最小二乘法对实验数据进行非线性回归 ,得到了 3种碱液浸取提钒的动力学方程式。由动力学方程式计算的钒浸取转化率与实验值绝对偏差不超过 6% ,平均偏差小于 3 %。通过比较化学反应与内、外扩散过程阻力的大小 ,证实了在实验条件下 ,浸取过程的控制步骤为化学反应控制。 3种碱液浸取反应的活化能分别为 2 0 .5 0kJ/mol、45 .74kJ/mol和 42 .3

Vanadium was extracted from HDS spent catalyst by the air roasting-alkali leaching method. The kinetics of leaching vanadium from roasted products was investigated using Na 2CO 3-H 2O, NH 4HCO 3-H 2O and NH 3·H 2O, respectively. Nonlinear regression of the experimental data was made using least square method, obtaining kinetics equations for vanadium extraction by alkali leaching. The absolute error between the equationally-calculated vanadium recovery and the experiementally-measured vanadium recovery was less than 6%, averging below 3%. By comparing the chemical reactions and the resistantes during inner or outer diffusion, the control steps in leaching were confirmed to be chemical reaction. The 3 alkali solutions during leaching had activation energies of 20.50 kJ/mol, 45.74 kJ/mol and 42.31 kJ/mol, respectively.