title: Measurement of Cu and Zn adsorption onto surficial sediment components: new evidence for less importance of clay minerals.
abstract: Clay minerals in surficial sediment samples, collected from the Songhua River in China, were separated via sedimentation after removal of Fe/Mn oxides and organic materials; Cu and Zn adsorption onto the sediment components was then evaluated. Clay minerals were examined via X-ray diffraction and scanning electron microscopy. Clay minerals were found to consist mainly of illite, kaolinite, chlorite and an illite/smectite mixed layer. Non-clay minerals were dominated by quartz and orthoclase. The retention of Cu and Zn by clay minerals was 1.6 and 2.5 times, respectively, greater than that of the whole, untreated surficial sediment. Compared to the other critical components in sediments related to metal sorption (Mn oxides, Fe oxides and organic materials), the adsorption capacity of clay minerals was found to be relatively lower on a unit mass basis. These data suggest that, although clay minerals may be important in the adsorption of heavy metals to aquatic sediments, their role is less significant than Fe/Mn oxides and organic materials.
authors.affiliation: College of Plant Science, Jilin University, 5333 Xi'an Road, Changchun 130062, China. wang xl@jlu.edu.cn
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Wang
authors.forename: Yu
authors.initials: Y
authors.lastname: Li
mesh_terms: D000327:Adsorption; D000538:Aluminum Silicates / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry; D002681:China; D000077215:Clay; D003300:Copper / Q000737:chemistry*; D004784:Environmental Monitoring; D005290:Ferric Compounds / Q000737:chemistry; D019015:Geologic Sediments / Q000737:chemistry; D008345:Manganese / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry; D010087:Oxides / Q000737:chemistry; D045483:Rivers; D012987:Soil / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis; D014961:X-Ray Diffraction; D015032:Zinc / Q000737:chemistry*
chemical_list: D000538:Aluminum Silicates; D005290:Ferric Compounds; D009930:Organic Chemicals; D010087:Oxides; D012987:Soil; D014874:Water Pollutants, Chemical; C000499:ferric oxide; D008345:Manganese; D002244:Carbon; D003300:Copper; D015032:Zinc; D000077215:Clay