Preparation Of Modified Biological Activated Carbon And Its Treatment Of Poor Water Containing Fluorine

High-fluorine water is widely distributed in the world,and china is also one of the countries where high-fluorine water is more seriously damaged.It is harmful to human health if people drink high-fluorine water for long time.In today's increasingly scarce water resources,it is particularly important to treatment of high-fluorine water.In order to explore the treatment of fluoride ion in high-fluorine inferior water,the three biological activated carbons prepared were modified to obtain three modified biological fluoride removal materials,and their fluoride removal performance was studied.The specific research content is as follows:?1?Preparation of iron-modified pig manure and its fluoride removal performanceThe pig manure was used as raw material,biological activated carbon?ZC?was prepared by high-temperature calcination,and iron modified biological activated carbon?Fe-ZC?was prepared after ZC impregnated Fe³⁺.The SEM and FTIR were used to characterize the structure and morphology of Fe-ZC.The defluoridation performance of Fe-ZC was studied,and the kinetic characteristics of the isothermal adsorption were discussed theoretically.The results showed that when the adsorption time was 120min,the pH was 7 and the dosage was24g/L,the removal rate of fluoride ion in high-quality fluoride water was over 90%.Among them,CO₃^2-,HCO₃^-,PO₄^3-have a significant effect on the effect of fluoride removal,and the effect size is CO₃^2->HCO₃^->PO₄^3-.The adsorption process of Fe-ZC on fluoride ion is a quasi-second-order kinetic equation,which is in accordance with the Langmuir isothermal model.?2?Preparation of alumina modified kiwifruit carbon and its fluoride removal performanceUsing kiwifruit as raw material,high-temperature roasting to obtain biological activated carbon?MC?,MC was impregnated with aluminum chloride solution,and then heating at300°C for 2h to obtain aluminum-loaded biological activated carbon?Al-MC?.The structure and morphology of Al-MC were characterized by SEM and FTIR.The preparation conditions were discussed.The studies have shown that when the AlCl₃ concentration is 0.3mol/L and the heating temperature is 300°C,the obtained material has the best fluoride removal effect.At the same time,the effects of dosage,initial concentration,pH value,time and coexisting ions on fluoride ion removal performance were studied.Single factor tests showed that the initial concentration and pH value had a great influence on the removal rate of fluoride ions.The effects of HCO₃^-,CO₃^2-,and PO₄^3-on fluoride removal were CO₃^2->HCO₃^->PO₄^3-.The response surface test showed that the functional relationship between fluoride ion adsorption capacity and factors can be fitted by regression equation.The factors affecting size are:initial concentration>pH value>dosing amount;the optimal condition for obtaining fluoride ion adsorption is that when the amount of Al-MC added was 0.3 g,the initial concentration was15 mg/L,and the pH was 7,the amount of adsorption was 18.83 mg/g.?3?Preparation of cerium nitrate modified bamboo charcoal and its fluoride removal performanceBioactive activated carbon?ZuC?was prepared from bamboo shavings as a raw material by high-temperature calcination,and La-ZuC bioactive activated carbon?La-ZuC?was prepared by impregnating thorium nitrate with zirconium.The structure and morphology of La-ZuC were characterized by SEM and FTIR.At room temperature,the effects of adsorption time,pH value,dosage and initial concentration on the fluoride ion removal performance were studied.The single factor test showed that the adsorption equilibrium time was 120 minutes.When the concentration of fluorine-containing inferior water was 5 mg/L,the fluorine removal rate was 98.6%.At 25 mg/L,the fluorine removal rate decreased to 35.12%,while the adsorption capacity increased to 29.27 mg/g.The effects of HCO₃^-,CO₃^2-,and PO₄^3-on fluoride removal were CO₃^2->HCO₃^->PO₄^3-.The effects of four factors,such as dosage,initial concentration,pH,and time,on the adsorption capacity of fluoride ions in poor-quality water were orthogonally tested.The influence of the four factors on the amount of fluoride adsorption was the initial concentration,dosage,pH,and time.The optimum adsorption conditions was that:pH was 7,initial concentration was 15 mg/L,dosage was 0.3 g.Under this condition,the fluoride adsorption capacity of La-ZuC can reach 12.65mg/g.