Preparation Of Defluoridators And Study On Their Defluoridation Properties From Containing Fluorine In Drinking Water

At present,the distribution of high fluoride water is very wide,about 26 provinces, autonomous regions 5000 towns and villages,water up to 77 million population, mainly concentrated in the northeast,north and north-west,from north-east of the western in Jilin Province,Inner Mongolia,the northern part of the Loess Plateau in Shanxi,Ningxia and Jilantai Yanchi,Gansu,Qinghai,Xinjiang until the Lop Nor and Hami in eastern cities have fluoride,such as the distribution of disease,patients with dental fluorosis of 37.4 million,2.76 million fluoride in patients with bone disease. High fluoride drinking water of endemic fluorosis caused by disease,the incidence of region is quite wide,the number of patients is great,and illness of the people is serious,and has far-reaching effects on people's health and economic development,so it has become a society question that can not be neglected.In view of this topic widespread problem of high fluoride water,based on a new type of adsorbent which could apply to a vast number of drinking water in rural areas to deal with low-cost, efficient,safe,simple;through a series of experimental studying the situation of adsorbent adsorption;And then running to determine the dynamic parameters;Finally, the cold field of scanning electron microscope to observe the micro-structure and evolution of elements,as a means of analysis of new adsorbents and regeneration of the principle of adsorption.In this experiment the basis of preliminary experiments use a new type of modified method,through a chemical reaction of aluminum ion adsorption loading of fluoride to the soil surface for the adsorption,it's absorbent soil that contains aluminum.Then preparing a new type of adsorbent properties and effects of fluoride removal, regeneration methods and conditions,elements of the micro-scanning and a more detailed analysis of the experimental determination,including the adsorption kinetics, the initial fluoride ion concentration,different size,different solid-liquid ratio, different pH value,different temperature,different hardness and metal cation On the effect of adsorbent adsorption experiments.Through the adsorbent under a long-term experimental study of the dynamic properties of adsorbent to determine the parameters of the practical application,comparing the advantages and disadvantages of two methods to determine regeneration conditions for renewable,finally,use electronic scanning microscope to analyze adsorbent microstructure and changes in ion content,from the macro-and micro-full understanding of the situation of adsorbent, to give the theoretical basis after their promotion. The main conclusions as follows:(1) Vector of different soil types of sorbents prepared by the adsorption effect of a certain degree of difference,but on the whole adsorption modified clay better.Used in this experiment is contained in the principle of aluminum chloride and ammonium bicarbonate in the case of the release of hydrolysis of carbon dioxide,and then roasted at high temperature under the load of aluminum in the soil in order to achieve the purpose of preparation.(2) In static experiments,with the increase in reaction time,the concentration of fluoride ion is decreasing;adsorbent adsorption capacity is increasing,and finally reaches saturation.With the increasing ratio of water and soil,amount of adsorbent adsorption is also increasing until saturation.Greater than the 1:150 ratio of solid to liquid the adsorbent is saturated.On low concentration of fluoride in solution,the new soil containing aluminum fluoride ion adsorbent has the adsorption of advantage.(3) With preparation of the adsorbent in this study increasing the size,the adsorption capacity is decreasing,compositing adsorption effects,operation and conservation, the choice of adsorbent particle size is between 0.6-3mm.Fluoride in the water,iron ions,the fluoride ion concentration with the increase of adsorbent adsorption capacity of iron is also a slight increase.(4) The results of column adsorption experimental show that the new adsorbent for fluoride ion in soil with good adsorption capacity of water in multiples of 100.A new type of regenerated adsorbent soil shows a downward trend in adsorption,but after repeating regeneration,the adsorption capacity remains basically unchanged,and stability in the 0.1 mg/g or more renewable capacity to maintain about 90%.Under long-term operation of the dissolution of aluminum is less than the national standard, in line with the drinking water use.(5) Through the experimental comparison,alum solution method has good effect of regeneration,compared with 5%of experiments to determine the alum solution to the ratio of 1:1 for 24 hours of immersion as a new set of aluminum sorbent regeneration method.The new type of soil in water stable adsorbent,adsorbent basic long-running will not be affected by the pressure of crushing,washing in the regeneration process after only a small amount of soil by the hydraulic shock into powder has good application prospects.(6) Finally,use the more advanced world of the cold field electron to scan microscope modified for the new modified adsorbent before and after,before and after regeneration and long-term operating conditions,respectively,the structural analysis of scanning and ion content.First of all,this article can be seen by scanning the modified process is more successful;have a uniform distribution of ions carried in the soil surface,especially aluminum ion load.Followed by the regeneration method is properly before and after the adoption of renewable element analysis can be seen soaking solution with alum aluminum ions again after the load to the soil to restore the adsorption capacity.Finally,the ultimate test sample,that is,in the long-term pressure of the adsorbent under the micro-scanning,found that because the pressure of the outside world faces adsorbent sheet-like structure is increased,but there is no structural damage to adsorbent,adsorbent stability is better..This study is to determine the soil as the carrier of the preparation of a new type of adsorbents,process simple,low-cost option for reducing the burden on farmers to reduce the fluoride removal costs,remote rural areas to solve the high fluoride drinking water is of great significance.