摘要
土壤与水体中的锰氧化物对某些重金属离子有强烈的富集作用 ,本研究表明我国几种土壤铁锰结核中锰氧化物的重金属离子 (Pb、Cu、Zn、Co、Ni和Cd)吸附量占结核吸附这些离子总量的 60 %～ 1 0 0 %。结核中所含锰矿物类型不同 ,对重金属离子吸附的能力不一样。山东砂姜黑土中含钙锰矿和锂硬锰矿 ,其锰氧化物的重金属离子吸附量最高 ;其次是湖北黄棕壤和黄褐土中铁锰结核的锰氧化物 ,它们为锂硬锰矿与水钠锰矿组合 ;吸附量最低的是湖南红壤中铁锰结核的锰氧化物 ,它们仅为锂硬锰矿。上述几种锰矿物构造上的差异和结晶程度不同是导致不同土壤铁锰结核中锰氧化物吸附重金属离子量不一样的重要原因。Co2 +在吸附过程中被氧化及试样中氧化锰含量和Mn(Ⅳ )百分率不同也是影响其铁锰结核中Co吸附量变化的原因。
Some heavy metal ions were s tr ongly adsorbed by Mn oxide minerals in soils and aquatic environment.The results showed that the amount of heavy metals(Pb,Cd,Co,Cu,Ni,Zn)adsorbed by Mn oxide m inerals in Fe Mn nodules in soils from China accounted for 60～100 percentage o f the total amount of the heavy metals absorbed by the Fe Mn nodules.The heavy metals adsorption capacity varied with types of Mn oxide minerals in the Fe Mn nodules.The amount of heavy metals adsorbed by Mn oxide minerals which contained todorokite and lithiophorite in Fe Mn nodules of Shajiang black soils in Shand ong province was the highest,that of yellow brown soil and yellow cinnamon soi l in Hubei province with birnessite and lithiophorite next,and that of red soil in Hunan Province which contained only lithiophorite the lowest.Difference in s tructure and crystallinity of the Mn oxide minerals led to different amounts of heavy metals adsorbed by Mn oxide minerals in the Fe Mn nodules.The contents of Mn oxide minerals and percentage of Mn(Ⅳ)in nodules affected the amounts of Co 2+ adsorbed by Fe Mn nodules because Co 2+ was oxidized to Co 3+ in the process of Co 2+ adsorption.
出处
《土壤学报》
CAS
CSCD
北大核心
2002年第5期699-706,共8页
Acta Pedologica Sinica
基金
国家自然科学基金项目资助 (批准号 :49771 0 49)
