Mn-Al双金属氢氧化物的制备及其除氟性能

Preparation of Mn-Al Double Hydroxide Adsorbent and Its Application to Fluoride Adsorption

采用共沉淀法制备Mn-Al双金属氢氧化物吸附剂,优化了合成条件,并利用扫描电子显微镜(Scanning electron microscope,SEM)及能谱分析仪(Energy dispersive spectrometer,EDS)、X射线衍射仪(X-ray diffraction,XRD)、热重分析仪(Thermogravimetric analyzer,TGA)、比表面积分析仪(Brunauer-Emmett-Teller surface area,BET)等对吸附材料进行表征探讨。研究结果表明pH值和共存离子等因素对Mn-Al双金属氢氧化物吸附剂除氟效能有一定的影响,在pH为6时,达到最大吸附容量,为44.15mg·g-1,氯离子和硝酸根离子能够提高吸附剂除氟效率,磷酸根离子与氟离子有一定的竞争吸附。

A novel adsorbent of Mn-Al double hydroxide for removing fluoride was prepared using coprecipitation method according to the optimal preparation conducted by this experiment.The prepared adsorbent was characterized by scanning electron microscope（SEM）,energy dispersive spectrometer（EDS）,X-ray diffraction（XRD）,thermogravimetric analyzer（TGA）,Brunauer-Emmett-Teller surface area（BET）.Based on current results,it reveals that the adsorbent belongs to amorphous structure with part of aggregated nanoparticles.According to the effect of pH value and competitive anions on defluoridation by Mn-Al adsorbent,the maximum fluoride adsorption capacity of Mn-Al adsorbent is 44.15mg·g^-1 while pH value is controlled at 6.The presence of chloride and nitrate ions could enhance the removal of fluoride by Mn-Al adsorbent while phosphate ion acts oppositely.