摘要
生物成因施氏矿物虽然在吸附As(Ⅲ)能力上表现出较其它吸附剂更为优越的吸附性能,但其制备过程中细菌分泌的多糖类物质使得矿物颗粒间存在明显的团聚现象.本研究通过比较不同预处理方法对施氏矿物矿物学特征及吸附性能的影响,寻求一种最佳的矿物预处理方法,以期进一步改善矿物颗粒团聚现象和提高对As(Ⅲ)吸附能力.采用NaOH、NaCl、200℃灼烧及乙醇-超声方法对施氏矿物进行预处理,结果表明,处理后矿物的矿相均未发生变化,但其理化性质随处理方式的不同差异较大,矿物比表面积、Fe/S摩尔比、SEM图谱、As(Ⅲ)吸附性能与原始矿物相比均发生了明显的变化.经pH 12NaOH处理后矿物的吸附性能最佳,在室温下最大吸附量从原来的101.9 mg.g-1增加到143.3 mg.g-1,比表面积从原来的45.63 m2.g-1增加到325.18 m2.g-1,矿物干燥时团聚现象明显减弱.
Biogenic schwertmannite has better absorption performance for As（Ⅲ） than other adsorbents,but there is obvious agglomeration of mineral particles due to the polysaccharides secreted by the bacteria during the synthesis of schwertmannite.The aim of this study was to find out a best pretreatment method to further reduce the agglomeration of mineral particles and enhance the As（Ⅲ） absorption capacity by comparing the effects of different pretreatment methods on the mineralogical characteristics and adsorption performance of schwertmannite.The pretreatment methods of the biogenic schwertmannite induding the treatments with NaOH,NaCl,thermal activation at 200℃ and ethanol-ultrasound.The results showed that the mineral phases were not altered after pretreatment,however,different physical and chemical properties of schwertmannite were found after different pretreatment methods were used.Compared with the original mineral,the mineral surface area,Fe/S molar ratio,SEM image and As（Ⅲ） adsorption were significantly changed.The highest As（Ⅲ） sorption capacity was obtained for the pH 12 NaOH treated schwertmannite with the maximum absorbance at room temperature increased from 101.9 mg·g-1 to 143.3 mg·g-1,and the surface area enhanced from 45.63 m2·g-1 to 325.18 m2·g-1.Besides,aggregation of mineral particles was remarkably decreased.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2012年第10期3606-3612,共7页
Environmental Science
基金
国家自然科学基金项目(21077053
40930738)
