摘要
研究了铜在碱渣表面的吸附特征.结果表明,碱渣总吸附量随体系温度的升高而降低;随体系pH值的升高而增加;随吸附质初始浓度的增加而增大.在pH<5.01时其等温吸附能较好地符合Freud lich等温吸附规律,而在pH>5.01时,能较好地符合Langmu ir等温吸附规律,吸附热随pH值的增大而升高.当pH≤4.54时,碱渣的吸附力以偶极间力和氢键力的作用为主,而当pH>4.54时,以化学键力为主.碱渣的动力学方程亦随pH值的改变而改变,在pH=4.54时,碱渣对Cu2+的吸附动力学方程以一级动力学方程拟合效果最优;当pH为4.91和6.01时,以Langmu ir方程的拟合效果最优.
Adsorption characteristics of copper ions on the surface of alkaline sludge were studied in this paper. Resuits showed that the total adsorption amount was increasing with the system temperature and pH decrease. The adsorption isotherm, adsorption heat and adsorption bond force were all related to the pH. The adsorption data were best describe by Freundlich equation when pH 〈 5.01 and by Langmuir when pH 〉 5.01. The increase of pH resulted in an increase of the adsorption heat on alkaline sludge. The adsorption forces of copper ions on alkaline sludge varied substantially with the changes of pH, while dipole bond force and hydrogen bond force dominated when the pH ≤4. 54 and chemical bond force became the main force when the pH 〉 4. 54. The adsorption kinetics of alkaline sludge was also correlated with medium pH value. When pH = 4. 54, the adsorption kinetics can be best described by first-order equation; while the Langmuir equation did when pH = 4. 91 and pH = 6. 01.
出处
《环境化学》
CAS
CSCD
北大核心
2006年第4期414-419,共6页
Environmental Chemistry
基金
国家自然科学基金资助项目(20307009).
关键词
碱渣
铜
吸附
吸附动力学
热力学.
alkaline sludge, copper, adsorption, adsorption kinetics, thermodynamics.
