钼酸铵晶体生长动力学研究

研究了四钼酸铵(AQM)晶体生长速率、反应历程和控制性步骤。结果表明：AQM晶体线生长速率(L)在0.3～1.75um/min范围内。过饱和生成速度大于消除速度的结晶初期，结晶过程处于相变反应控制的动力学区域，该区域L和溶液过饱和度(△C)由上升到下降。当过饱和消除速度增大到与生成速度相等时，过程转变为由Mo8 O26^4-聚合反应控制的化学反应区域，此区域L和△C处于稳定不变的状态。结晶后期L(即△C)不变时，成核速率N却依然快速升高的特征表明，AQM成核大部分是在首先接触到无机酸的局部溶液中完成的。

SYUDY ON CRYSTAL GROWINGKINETICS OF AMMONIUM MOLYBDATE

The rate of crystal growth,reaction mechanism and control step of AQM were studied.Results showed that the linear rate() of crystal growth of AQM was at the range of 0.3～1.75 μm/min.In the initial crystallization stage which the growing speed of supersaturation was more than the relaxing speed,the crystallization was situated in kinetic region of phase transformation reaction control.In this region, and the oversaturation of solution was going from up to down.When the relaxing speed of oversaturation increased to be equal to the growing speed,crystal process changed to the chemical reaction region controlled by Mo8O4-26 polymerization.In this region,the linear rate of growing speed and oversaturation were stable.In the end of crystallization when the linear rate of growing speed was stable,the rate of nucleation speed rised rapidly.It showed that the nucleation of AQM was mostly finished in the local solution which met inorganic acid first.