Trace metals partition between aqueous and solid phase in a river water

• Main Authors: Lai, Yu-sheng, 賴佑昇
• Other Authors: Chen, Ting-Chien
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/14323715469066877269

碩士 === 國立屏東科技大學 === 環境工程與科學系所 === 102 === Heavy metal pollution is a common environmental pollution around the world. The concentration and distribution of heavy metals affect their fate, toxicity and transport in the environment. This study collected water samples and suspended particulate matters (SPM) from river water. The water dissolved organic matter (WEOM) and humic substances (HS) solutions were extracted from the SPM samples. The filtrate, WEOM, and HS solutions were separated into different molecular weight solution with tangential flow ultrafiltration. All the samples measured concentrations of heavy metal and dissolved organic carbon. Samples of filtered water and SPM showed that highest concentration was Cu, followed by Mn, and the lowest concentration was Ni. In the water samples, low molecular weight dissolved organic matter (DOM) had the highest Cu, Mn, and Ni fractions. However, Cu, Mn, and Ni concentrations with organic carbon were influenced by the source of organic carbon and metal having the greatest variations. Heavy metal concentrations in HS were about 2 to 10 fold the concentrations in WEOM. However, metal concentrations with organic carbon in WEOM were greater than the concentrations in HS. Average heavy metal partition coefficients, log Kp, ranged from 3.6 to 4.5 (L/kg) between water and SPM samples and the order of log Kp was Ni > Cu > Mn. The Cu and Ni masses in HS were greater than the mass in WEOM, but the Mn mass in WEOM was greater than in the HS. The heavy metal distribution coefficients, Koc, between the high and low molecular weight DOM of the water samples ranged from 0.39 to 1.09, while the majority of Koc was less than 1.0. Moreover, Koc values had a positive correlation with corresponding metal concentration ratios. Keyword:Trace metals、Suspended particulate matter、Tangential flow ultrafiltration、Partition coefficient