摘要
研究了水溶液中二价阳离子(Cu、Ni、Co和Zn)与商业化腐植酸(HAAl)和泥炭腐植酸(HAPs)的相互作用。研究采用修正的兰缪尔方程拟合了一系列吸附等温曲线。实验发现,HAAl对前述金属离子的最大吸附摩尔数分别为0.55±0.02 mmol/g,0.66±0.02 mmol/g,0.54±0.02 mmol/g,0.40±0.02 mmol/g,HAPs对它们的最大吸附摩尔数分别为:0.63±0.03 mmol/g,0.61±0.06 mmol/g,0.55±0.02 mmol/g,0.54±0.03 mmol/g。对于相同的序列,HAAl和HAPS之间的相互作用所吸收的热量值分别为2.4±1.0 mmol/g,8.4±0.9 mmol/g,18.3±0.9 mmol/g,10.6±0.9 kJ/mol,和18.4±1.2 mmol/g,15.9±1.4 kJ/mol,15.4±1.2 kJ/mol,15.0±1.2 kJ/mol。由于吉布斯自由能为负,离子络合作用过程必然伴随着熵的增加。
The adsorption behavior of divalent cations M2＋（Cu, Ni, Co and Zn） with commercial humic acid （HAAl） and also withan extracted fraction of peat soil （HAPs） was followed in aqueous solution. The series of adsorption iso-therms were ifttedto a modiifed Langmuir equation. The maximum number of moles adsorbed gave：0.55 ± 0.02 mmol/g, 0.66 ± 0.02 mmol/g, 0.54 ± 0.02 mmol/g, 0.40 ± 0.02 mmol/g for HAAl and 0.63 ± 0.03 mmol/g, 0.61 ± 0.06 mmol/g, 0.55 ± 0.02 mmol/g, 0.54 ± 0.03 mmol/g for solid HAPs, for copper, nickel, zinc and cobalt, respectively. The same in-teraction followed calorimetrically gave endothermic values：2.4 ± 1.0 kJ/mol, 8.4 ± 0.9 kJ/mol, 18.3 ± 0.9 kJ/mol, 10.6 ± 0.9 kJ/mol and 18.4 ± 1.2 kJ/mol, 15.9 ± 1.4 kJ/mol, 15.4 ± 1.2 kJ/mol, 15.0 ± 1.2 kJ/mol for HAAl and HAPs, respec-tively, for the same sequence. Because all Gibbs free energies were negative. Complexation must beaccompanied by an increase in entropy.
出处
《腐植酸》
2013年第5期33-36,共4页
Humic Acid
关键词
腐植酸
热力学数据
二价阳离子
吸附
humic acid
thermodynamic data
divalent cations
adsorption
