摘要
研究天然海泡石和2种不同方法改性的海泡石对Pb吸附的影响.结果表明,不同Pb初始浓度、海泡石使用量、pH值和温度均对天然海泡石和改性海泡石吸附Pb有不同的影响.天然海泡石和改性海泡石对Pb的吸附量均随着溶液pH的提高而增加.海泡石经过氧化氢改性后可极大地促进其对Pb的吸附.天然海泡石和改性海泡石对Pb的等温吸附可用Langmuir方程和Freundlich方程来拟合,Langmuir方程的拟合效果最好,相关系数在0.9153—0.9702之间.低浓度的Ca2+和Mg2+(2—5 mmol·L-1)均抑制天然海泡石和改性海泡石对Pb的吸附,而高浓度的Ca2+和Mg2+(10 mmol·L-1)却促进天然海泡石和改性海泡石对Pb的吸附.当Ca2+和Mg2+浓度都为10 mmol·L-1时,天然海泡石吸附Pb量分别比对照提高126.6%和137.8%,过氧化氢改性海泡石吸附Pb量分别提高32.1%和19.8%,硝酸钠改性海泡石吸附Pb量分别提高58.8%和57.9%.
Adsorption of Pb on the natural sepiolite and two modified sepiolites were studied. The results showed that the adsorption of Pb was influenced by the initial lead concentration, the dosage of sepiolite, solution pH value and temperature. The adsorption capacity of Pb on natural and modified sepiolite all increased with increasing solution pH. H202 treated sepiolite improved the adsorption of Pb. Adsorption of Pb on natural and modified sepiolite could be well fitted by Langmuir isotherm equation and Freundlich equation. The equilibrium process was better described by Langmuir equation, and the correlation coefficient was 0. 9153--0. 9702. Low concentration of Ca2＋ and Mg2＋ （2--5 mmol. L-l ） inhibited the adsorption of Pb by natural and modified sepiolite, while high concentration of Ca2＋ and Mg2＋ （ 10 mmol＇L--1 ） promoted the adsorption of Pb by natural and modified sepiolite. Compared to the control treatment, addition of 10 mmol.L-1 Ca2＋ and Mg2＋ increased Pb adsorption by 126.6% and 137.8% respectively on natural sepiolite, by 32.1% and 19.8% respectively on H2O2 modified sepiolite, and by 58.8% and 57.9% on KNO3 modified sepiolite.
出处
《环境化学》
CAS
CSCD
北大核心
2013年第11期2024-2029,共6页
Environmental Chemistry
基金
国家重金属污染治理专项"广西环江县大环江流域土壤重金属污染治理工程项目"
中国科学院院地合作项目"江西省典型矿区及周边土壤重金属污染特征及其联合修复技术研发"
国家水体污染控制与治理科技重大专项(2009ZX07212-001-05)资助
关键词
海泡石
改性
PB
吸附
影响因素
sepiolite, modify, Pb, adsorption, effective factor.
