紫色水稻土有机无机复合体对磷的吸附动力学特性

Kinetic characteristics of p adsorption in purple paddy organo mineral complex

选择了四川典型的３种紫色水稻土有机无机复合体，并用液流法研究其对磷酸盐的吸附动力学特性．结果表明，在反应的２ｈ内，灰棕紫泥低肥力水稻土和红紫泥低肥力水稻土的有机无机复合体磷吸附过程以复一级反应为特征．反应开始２０ｍｉｎ内存在理想的线性关系（ｒ＝－０．９９９，ｎ＝１０；ｒ＝－０．９９９，ｎ＝９），２０ｍｉｎ至２ｈ间存在另一线性关系（ｒ＝－０．９９７，ｎ＝１１；ｒ＝－０．９９６，ｎ＝１２）．红棕紫泥高肥力水稻土复合体的磷吸附过程以单一级反应动力学为特征（ｒ＝－０．９９８，ｎ＝２１），并在４０ｍｉｎ左右内抛物扩散律拟合较好（ｒ＝－０．９９７，ｎ＝１５）．它们的表观活化能分别为３３．０４，９．３６和６．４１ｋＪ／ｍｏｌ．

Liquid flow method was used to investigate the kinetic characteristics of P adsorption in purple paddy organo mineral complex for the first time.The P adsorption of organo mineral complex in neutral and acid paddy soils developed from purple soils had two different kinds of mechanism by simulating the first order kinetic equation,these two simultaneous different mechanisms determined by simulating parabolic diffusion equation were attributed to the diffusion controlled process of P adsorption.The P adsorption process of organo mineral complex in calcareous paddy soils developed from purple soil comformed to the single first order kinetic equation ( r=0 998,n=21 ) and parabolic diffusion equation ( r=0 997,n=15 ) within forty minutes.Their Arrhenius activation energies were 33 04kJ·mol -1 ,9 36 kJ·mol -1 and 6 41 kJ·mol -1 respectively as the result of diffusion controlled processer.The P adsorption process in organo mineral complex was endothermic.