道路雨水径流溶解性有机物与重金属结合作用分析

Complexation between heavy metals and dissolved organic matters in road stormwater runoffs

为了解道路雨水径流溶解性有机物(DOM)与重金属的相互作用,采用荧光激发-发射矩阵光谱、超滤、离子选择电极法及红外光谱等技术对道路雨水径流溶解性有机物及其组分同Cu^(2+)、Pb^(2+)和Cd^(2+)的络合作用进行了研究.结果表明,道路雨水径流DOM与3种重金属离子的络合作用由强到弱依次是:Cu^(2+)>Pb^(2+)>Cd^(2+),4种分子量DOM组分与重金属之间均发生了络合反应,且DOM组分分子量越小,与重金属之间的络合作用越强.4个不同分子量区间的DOM组分与Cu^(2+)、Pb^(2+)和Cd^(2+)之间的络合作用由强到弱的顺序为:<1 kDa组分、1~10 kDa组分、10~30kDa组分、30 kDa^0.45μm组分.

Dissolved organic matters（ DOM） and DOM fractions in road stormwater runoffs complexation with Cu2＋,Pb2＋and Cd2＋were investigated by three-dimensional fluorescence spectroscopy,ultrafiltration membrane separation,ion-selective electrodes and infrared spectroscopy. The results showed that the complexation ability between heavy metals and DOM was following in the order of Cu2＋ Pb2＋ Cd2＋. DOM fractions with different molecular weight could combine with heavy metals. The molecular weight of DOM fractions was lower,the complexation ability was stronger. The complexation ability between heavy metals and DOM fractions with different molecular weight was following in the order of 1 kDa,1 - 10 kDa,10 - 30 kDa,30 kDa -0.45 μm.