摘要
以火电厂固废粉煤灰为主要原料,采用改良水热法研制合成了低成本的P型沸石,对其进行了稀土镧改性处理,以强化其脱氮除磷能力.实验研究了改性镧离子浓度、投加量、pH值对同步去除氨氮和磷的影响;运用XRD和SEM分析技术对合成沸石进行了表征.结果表明,在改性镧离子浓度0.5%、pH值为4～8、投加量为10g/L时,改性后的合成沸石对氨氮和磷的去除率分别达到90%,95%以上.改性后的合成沸石对氨氮及磷的吸附动力学数据符合伪二级方程.Langmuir方程能更好地描述氨氮及磷在改性合成沸石上的等温吸附行为,氨氮和磷的Langmuir最大吸附量分别为3.94,1.65mg/g.
The low-cost P zeolite was synthesized from coal fly ash of power plants through the modified hydrothermal process,and further treated through the tombarthite La modification to improve its ammonium and phosphate removal efficiency.The experiments focused on testing the impact of modified lanthanum concentration,dosage,pH on ammonium and phosphate removal.X-ray diffraction（XRD） and scanning electronic microscope（SEM） were applied to observe the physical-chemical characteristics.Removal rate of ammonium and phosphate were 90%,95% respectively under the conditions of lanthanum concentration at 0.5%,pH 4～8,and the dosage of 10g / L.The adsorption process of ammonium and phosphate was in accord with pseudo-second-order kinetic model.The equilibrium adsorption data were fitted to Langmuir isotherms and the maximum adsorption capacity of ammonium and phosphate were 3.94,1.65 mg/g respectively.
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2011年第7期1152-1158,共7页
China Environmental Science
基金
国际合作项目(2009DFA91780)
东江高速都市化支流区水污染系统控制技术集成研究与工程示范(2008ZX07211-004)
关键词
粉煤灰
P型沸石
氮磷
镧离子改性
coal fly ash
P zeolite
ammonium and phosphate
La-modification
