摘要
分别采用NaC l、KC l和CaC l2对黑龙江省某市天然沸石进行改性,考察了pH值、氨氮初始浓度以及温度对改性沸石交换性能的影响,并对改性沸石的交换动力学进行了研究。结果表明,NaC l和KC l改性对沸石原矿交换容量有不同程度提高,而KC l改性后容量有所降低。pH、NH4+初始浓度以及温度对交换性能有明显影响,pH 6.0附近沸石交换容量最大;NH4+初始浓度越高,反应速度越快,相同初始浓度下,钾型沸石交换速度较快,而沸石原矿交换速度最慢。采用Lang-mu ir型离子交换等温线进行非线性回归的结果显示,低温有利于交换反应的进行。溶液中NH4+在改性沸石上的离子交换反应可采用Verm eu len模型描述,沸石原矿拟合相关系数较差。改性沸石多次再生后,其交换容量均有所降低。
Sodium chloride, potassium chloride and calcium chloride were adopted to modify the natural zeolite of Heilongjiang Province. The effects of pH,initial concentration of ammonia nitrogen and temperature on the ion exchange capability-of modified zeolites were studied.. Furthermore,kinetics of ion exchange was deduced. Results indicated that modification by sodium chloride and calcium chloride could improve the full exchange capabilities. But the full exchange capability was reduced when it was modified by potassium chloride. The pH of 6.0 seemed to be favorable to the exchange capabilities, and there was a positive correlation between the initial concentration of ammonia nitrogen and the velocity of ion exchange. Langmuir ion exchange isotherm indicated that low temperature was propitious to exchange reaction. Vermeulen model could be used to describe the ion exchange reactions of modification zeolites,but the zeolite ore showed a relatively bad correlation coefficient than others. The capabilities of modified zeolites were reduced by different degrees after many times of regeneration.
出处
《环境污染治理技术与设备》
CAS
CSCD
北大核心
2006年第3期75-79,共5页
Techniques and Equipment for Environmental Pollution Control
基金
国家"十五"科技攻关资助项目"城镇水环境关键技术"(2002BA806B04)
黑龙江省重点科技攻关资助项目(GB02C202-01)
关键词
天然沸石
改性
氨氮
离子交换
natural zeolite
modification
ammonia nitrogen
ion exchange
