摘要
以给水污泥为吸附材料,采用正交实验与单因素实验研究了多种因素对除磷效果的影响.正交实验结果表明最佳反应条件为:pH为3,粒径1.98 mm,投加量8.0 g/L,吸附时间24 h.结合SEM/XRD和EDS等表征方法,对给水污泥的表面形貌和结构特征进行表征和分析.Langmuir、Freun dlich和D-R等温吸附方程均能较好的拟合给水污泥对磷的吸附特征.在298、308和318 K温度下,Langmuir拟合得到的理论饱和吸附量分别为3.47、3.84和4.39 mg/g.由D-R方程计算的吸附自由能E为10.77 ~ 10.83 kJ/mol,表明吸附过程为离子交换吸附.
With alum sludge as the absorbent, the effects of various factors, including particle size, adsor- bent dosage, pH and contact time on adsorption, were studied by orthogonal experiment and single factor experi- ment. With the orthogonal experiment, optimal operating conditions and parameters were ascertained: the best pH of 3, the great particle size of 1.98 mm, the optimal adsorbent dosage of 8.0 g/L and contact time of 24 h. The surface's morphology and structure of the alum sludge were characterized and analyzed by the SEM, XRD and EDS. Langmuir, Freundlieh and Dubinin-Radushkevich(D-R) isotherms models were used to greatly de- scribe the kinetic data, and the Freundlieh equation was the best model. When the temperature was 298 K, 308 K and 318 K, respectively, the saturated extents of adsorption of phosphorous were 3.47 mg/g, 3.84 mg/g and 4.39 mg/g separately. The adsorption free energy value (E = 10.77 - 10.83 kJ/mol) calculated by the D-R e- quation indicated that the adsorption was controlled by the ion exchange adsorption.
出处
《环境工程学报》
CAS
CSCD
北大核心
2015年第8期3659-3666,共8页
Chinese Journal of Environmental Engineering
基金
国家"水体污染控制与治理"科技重大专项(2012ZX07206-004-002)
中央级公益性科研项目(PM-zx021-201211-128)
关键词
给水污泥
磷
吸附
正交实验
单因素实验
等温吸附模型
alum sludge
phosphorus
adsorption
orthogonal experiment
single factor experiment
isotherms