The kinetic behaviours of the substitution reaction of rare earth-PHA with CyDTA were studied systemati- cally.The relationship between the rate constant and atomic number was discussed.The rate differentiation val- u...The kinetic behaviours of the substitution reaction of rare earth-PHA with CyDTA were studied systemati- cally.The relationship between the rate constant and atomic number was discussed.The rate differentiation val- ue R_d(R_d=lgk_(z+n)-lgk_z)was proposed to evaluate the possibility of differential kinetic analysis.The R_d value between the neighbouring lanthanide ions first increases and then decreases along with increasing atomic number, so that the middle and heavy rare earth mixture(such as Sm-Gd and Gd-Y)are ideal systems for the differential rate kinetic analysis.展开更多
文摘The kinetic behaviours of the substitution reaction of rare earth-PHA with CyDTA were studied systemati- cally.The relationship between the rate constant and atomic number was discussed.The rate differentiation val- ue R_d(R_d=lgk_(z+n)-lgk_z)was proposed to evaluate the possibility of differential kinetic analysis.The R_d value between the neighbouring lanthanide ions first increases and then decreases along with increasing atomic number, so that the middle and heavy rare earth mixture(such as Sm-Gd and Gd-Y)are ideal systems for the differential rate kinetic analysis.