硼污染土壤中硼释放特征及无机离子对其释放的影响  

The Characteristics of Boron Release from Boron Contaminated Soil and the Inorganic Ion Effect on Boron Release

作　　者：刘莹[1] 梁成华[1] 杜立宇[1] 赵宇光[1] 

机构地区：[1]沈阳农业大学土地与环境学院,辽宁沈阳110161

出　　处：《农业环境科学学报》2009年第4期711-715,共5页Journal of Agro-Environment Science

基　　金：国家重点基础研究发展计划项目:典型城区与矿区水-土-气界面污染过程及生态风险(2004CB418504)

摘　　要：采用连续液流法研究了硼污染土壤中硼的释放动力学过程,并采用振荡平衡法就无机离子对硼释放的影响进行了研究。结果表明,(1)供试土壤硼的累计释放量随时间的延长而增大,累计释放量与全硼含量相关性不显著,而与土壤有效硼含量呈显著正相关。(2)准二级动力学方程是描述土壤硼释放动力学过程的最佳方程。(3)供试土壤各时段硼平均释放速率的自然对数与时间呈极显著的线性相关性,随时间延长反应速率不断下降。释放速率有阶段性特点,可分为快速反应阶段、中速反应和慢速反应三个阶段,释放的硼90%以上来自前两个阶段。(4)无机离子对供试土壤中硼表现出不同的释放能力,对释放量影响的大小顺序依次为:Cl->SO24->CO23-,Na+>Ca2+。Boron release as a function of time was measured for boron contaminated soils by liquid flow technique with 0.01 mol·L^-1 CaCl2 solution, and the inorganic ions genarally exsited in soil effects on boron release were studied by batch method. Four mathematical models（first order, pseudo-second order, Elovich and power function ） were used to describe Boron release. The relationship between release velocity and time was also disscussed by mathematical models .The results showed that, the cumulative amount of boron release increased with time and was independent of soil initial sample boron content. The release capacity was different in tested soils. Boron release equilibrated in the time of 240-255, 90-105, 135-150, 90-105, and 195-210 min, respectively. Comparison coefficients of determination（r^2） and standard errors of estimate （ se ）, pseudo-second order, Elovich and power function could describe Boron release, but Pseudo second-order equation was best fitted with experimental kinetic date. There was a linear relationship between the logarithm of the release velocity and time, and the velocity decreased with time fast. The kinetic reaction could be divided into three different phases, and the release percentage of boron from first two phases accounted more than 90% of the total release boron. The boron release reaction from tested soils was a rapid reaction, and the rest boron was difficult to be removed. The release capacity of different ions to boron release was different in tested soils, with significant differences among them（P〈0.001 ）, and the order was Cl^-〉SO4^2-〉CO3^2-,Na^＋〉Ca^2＋.

关 键 词：土壤污染 硼污染 释放动力学 

分 类 号：X53[环境科学与工程—环境工程]