摘要
施氏矿物作为一种具有良好应用前景的高砷吸附材料已倍受人们关注.采用静态吸附实验对生物、化学成因施氏矿物去除模拟地下水中As(Ⅲ)进行了研究.结果表明,在25℃,初始As(Ⅲ)浓度为0.2mg·L-1,施氏矿物投加量为0.25g·L-1时,生物成因施氏矿物吸附3h后溶液中As(Ⅲ)含量降低到10μg·L-1以下(地下水饮用标准),吸附最佳pH范围为6～10,化学成因施氏矿物在pH7～8,则需吸附平衡12h后溶液中As(Ⅲ)含量才能达到10μg·L-1以下.当介质中存在PO43-和SiO32-时,生物成因施氏矿物表现出对As(Ⅲ)专性吸附能力强于化学成因施氏矿物.等温吸附实验(25℃)表明,生物成因施氏矿物对As(Ⅲ)的最大吸附量为101.9mg·g-1,比化学成因施氏矿物(82.1mg·g-1)高出约24.1%,表现出更优异的吸附性能.
Schwertmannite has been focused on more and more on account of its extensive application prospect in removing arsenic in water and wastewater.Static adsorption experiments were carried out in this study to investigate the removal of As（Ⅲ） from simulated groundwater via adsorption of schwertmannite formed by biological or chemical procedures.The results showed that 0.2 mg · L-1 of initial As（Ⅲ） in simulated groundwater could be drastically reduced to lower than 10 μg · L-1 with 0.25 g · L-1 of biosynthesized schwertmannite at 25 ℃ after 3 h of adsorption.The optimum pH for As（Ⅲ） adsorption by biosynthesized schwertmannite was 6~10.However,chemosynthesized schwertmannite required at least 12 h to eliminate As（Ⅲ） of the same initial concentration to meet the discharge standard（10 μg · L-1）at pH 7~8.Moreover,biosynthesized schwertmannite exhibited stronger specific adsorption capacity of As（Ⅲ） than that of the chemosynthesized mineral in simulated groundwater with co-existing competing anions like PO3-4 or SiO2-3.In addition,the adsorption isotherm indicated that biosynthesized schwertmannite had a maximum sorption capacity of 101.9 mg · g-1 As（Ⅲ）,which was 24.1% higher than chemosynthesized schwertmannite（82.12 mg · g-1）.
出处
《环境科学学报》
CAS
CSCD
北大核心
2011年第5期912-918,共7页
Acta Scientiae Circumstantiae
基金
国家自然科学基金项目(No. 40930738
21077053)~~
