摘要
将粉煤灰(FA)与Na2CO3混合焙烧后浸渍负载Fe2+,制备了复合改性粉煤灰(CMFA)。通过多种手段对CMFA进行了表征,并将其用于含磷废水的吸附处理。表征结果显示:改性后的粉煤灰表面疏松多孔,比表面积增大了21倍,产生了金属盐类熔出物及羟基氧化铁和羟基官能团。实验结果表明:当初始磷质量浓度为50 mg/L、吸附温度为20℃、溶液pH为4.3、CMFA投加量为5 g/L、吸附时间为30 min时,磷去除率可达98.01%,较FA的50.10%大幅提升;20℃时,CMFA对磷的饱和吸附量可达22.15 mg/g;用拟二级动力学模型可较准确地描述CMFA对磷的吸附过程,该过程为自发的吸热过程,符合Langmuir等温吸附模型,为以离子交换为主的化学吸附。
Composite modified fly ash(CMFA)was prepared by impregnating Fe2+on calcination product of fly ash(FA)with Na2CO3.CMFA was characterized by a variety of means and used in the adsorption treatment of phosphorouscontaining wastewater.The characterization results show that the modified fly ash is porous on the surface with 21 times larger of the specific surface area,and molten metal salts,hydroxyl iron oxide and hydroxyl functional groups are produced.The experimental results show that:When the initial phosphorus mass concentration is 50 mg/L,the adsorption temperature is 20℃,the solution pH is 4.3,the CMFA dosage is 5 g/L and the adsorption time is 30 min,the phosphorus removal rate is 98.01%,significantly higher than 50.10%of that on FA;At 20℃,the saturation adsorption capacity of CMFA to phosphorus reached 22.15 mg/g;The adsorption process of phosphorus on CMFA can be accurately described by quasi-secondary kinetic model,which is a spontaneous endothermic process in accordance with the Langmuir isothermal adsorption model and a chemical adsorption process based on ion exchange.
作者
石家豪
韩非
邱磊
丁珣
SHI Jiahao;HAN Fei;QIU Lei;DING Xun(School of Civil and Transportation Engineering,Hebei University of Technology,Tianjin 300401,China)
出处
《化工环保》
CAS
CSCD
北大核心
2020年第2期180-185,共6页
Environmental Protection of Chemical Industry
基金
国家自然科学基金项目(51608165)。
关键词
复合改性粉煤灰
磷
吸附
废水处理
compound modified fly ash
phosphorus
adsorption
wastewater treatment
