摘要
高氟水在我国西北地区分布广泛,长期饮用高氟水易患全身性慢性疾病,甚至对人脑神经造成损害,使人丧失劳动能力。这不仅严重危害着当地人民的身体健康,也制约着当地的经济发展。层状双氢氧化物(LDH)具有优异的阴离子交换性能,在对高氟水的处理方面具有一定的优越性。通过以Al_(13)即时合成的镁铝型LDH与以AlCl_(3)即时合成的镁铝型LDH对高氟水进行处理进行对比,考察了各个影响因素以及反应条件对处理效率的影响。结果表明,该技术对含氟5 mg/L以下的高氟水地下水有良好的处理效率,在最佳反应条件下,出水可以达到世界卫生组织(WHO)所规定的饮用水卫生标准,降低高氟水给人体带来的危害。即时合成LDH较为适宜的反应条件为:溶液pH值为10.5,Mg^(2+)浓度为48 mg/L,Al_(13)浓度为0.06 mmol/L,Ca^(2+)浓度为20 mg/L,即Mg^(2+)/Ca^(2+)为2∶1,反应时间8 min,该条件下氟离子去除率可以达到70%左右。此时Mg^(2+)和Al_(13)水解较完全,综合去除效果最好,且生成固体中没有发现其他的物相。通过Mg/Al_(13)/MgAl_(13)-LDH的单独实验表明,相对于铝盐,即时合成LDH的去除效果更好。采用北大自来水为水样,在优化条件上,证明以Al_(13)即时合成的镁铝型LDH比以AlCl_(3)即时合成的镁铝型LDH对F^(-)的去除率更优。该方法可以在水处理过程中即时合成LDH,既能达到处理高氟水的目的,又省去了LDH在实验室合成过程中的复杂且严格的条件控制、固液分离、干燥以及粉碎等步骤。采用絮凝性能更好的Al_(13)为金属离子M^(3+)即时合成MgAl-LDH,用以处理高氟水效果更好,为将LDH应用于实际水处理方面提供了参考。
The high fluoride water are widely spread in the Northwest of China,drinking the high fluoride water will cause the loss of the work ability.This is not only severely impair the health of the local people,also restrict the local economic development.Therefore,high fluoride water purification,treatment has elicited great concern,adsorption method is an effective means of dealing with fluorinated water.Layered double hydroxides(LDH),its structure is similar to the layered structure of brucite interlayer anions and other anions can be exchanged with the outside world,which LDH has excellent performance anion exchange,in the high fluoride water treatment has some advantages.This paper will be studied the factors and optimum reaction conditions of MgAl_(13) LDH in dealing with high fluoride water.Then compared with the MgAlCl_(3)-LDH,treatment effect of MgAl_(13) LDH is better.The results show technology has good treatment efficiency for high fluorine groundwater containing fluorine below 5 mg/L.Under the best reaction conditions,effluent can reach the world health organization(WHO)drinking water hygiene standards by the rules,and reduce the harm of high fluorine water to human body.The suitable reaction conditions for the immediate synthesis of LDH are as follows:the pH value of the solution is 10.5,Mg^(2+)concentration of 48 mg/L,Al_(13) concentration of 0.06 mmol/L,Ca^(2+)concentration of 20 mg/L,that is,the ratio of Mg^(2+)/Ca^(2+)is 2∶1,and the reaction time is 8 min.The removal rate of fluoride ion can reach about 70%under these conditions.At this time,the comprehensive removal effect is the best,and no others phase is found in the generated solid.Experiment studied the pH value,Mg/Al/Ca concentration,F^(-)concentration on the initial,which impact with the removal of the law.And then use tap water as the water samples,make a further discussion about the actual treatment effect of LDH in the water.Finally,on the basis of previous experiments,determine the optimal reaction conditions and compared MgAl_(13) LDH w
作者
祁淑媛
张亚龙
郭飞刚
郝莹珂
马莹
何静
Qi Shuyuan;Zhang Yalong;Guo Feigang;Hao Yingke;Ma Ying;He Jing(Xi'an High-Tech Industries Development Zone Environmental Monitoring Centre,Xi'an 710077,China;High-Tech Zone Branch of Xi'an Ecological Environment Bureau,Xi'an 710055,China;PinBiao Environmental Technology Co.,Ltd.,Xi'an 710012,China)
出处
《能源与环保》
2022年第10期182-188,194,共8页
CHINA ENERGY AND ENVIRONMENTAL PROTECTION
基金
宁夏回族自治区重点研发基金项目(2019BFG02031)。
