Chemistry Department, Faculty of Science, Sohag University, Sohag, Egypt.
J Phys Chem A. 2012 Nov 15;116(45):10889-96. doi: 10.1021/jp3078826. Epub 2012 Nov 5.
Kinetics of humic acid (HA) adsorption onto soil minerals (kaolinite and hematite) has been investigated under various conditions. The influence of ionic strength, pH, and solution cations on the rate of adsorption has been studied. The rate and the amount of adsorbed humic acid onto soil minerals increased with increasing ionic strength, decreasing pH, and in the presence of Ca(2+) as background electrolyte. The adsorption equilibrium data showed that adsorption behavior of humic acid could be described more reasonably by Freundlich adsorption isotherm than Langmiur adsorption isotherm. Pseudo first order and pseudo second order kinetic models were used to evaluate the kinetic data and the rate constants. The results explained that humic acid adsorption on hematite and kaolinite was more conforming with pseudo second order kinetics.
已经在各种条件下研究了腐殖酸（HA）在土壤矿物质（高岭土和赤铁矿）上的吸附动力学。研究了离子强度、pH 值和溶液阳离子对吸附速率的影响。随着离子强度的增加、pH 值的降低以及以 Ca(2+) 作为背景电解质的存在，土壤矿物质上吸附的腐殖酸的速率和量增加。吸附平衡数据表明，腐殖酸的吸附行为可以用 Freundlich 吸附等温线比 Langmiur 吸附等温线更合理地描述。采用拟一级和拟二级动力学模型来评估动力学数据和速率常数。结果表明，腐殖酸在赤铁矿和高岭土上的吸附更符合拟二级动力学。
