pH值、离子强度和重金属离子对腐殖酸紫外谱图的影响

Effects of p H,ionic strength and heavy metal ions on UV spectras of humic acid

研究pH值、溶液离子强度和金属离子对腐殖酸紫外光谱的影响,分析腐殖酸的结构特征,探讨E3/E4与pH值和溶液离子强度的关系。结果表明,腐殖酸的紫外光谱吸收带,随pH值增大主要发生蓝移。但随溶液离子强度增大,pH值对腐殖酸紫外吸收带的影响逐渐降低直至不影响。随溶液离子强度增大,腐殖酸的紫外光谱吸收带都发生红移、吸收强度增大。且腐殖酸的E3/E4值与溶液离子强度具有显著的正相关性。腐殖酸的紫外光谱中的吸收带,随投加Cu2+或Cd2+浓度增大而发生红移。

The structure characteristics of humic acids（ HA） was analysed by studying the HA UV spectras affected by p H,ionic strength and the metal ions. And the relationships between E3 / E4 and the p H and ionic strength of the solution were discussed. The results showed that the absorption band of the HA ultraviolet spectrum occurred blue shift mainly with the increase of p H value. But this influence with the p H gradually reduced until the p H had no effect with the increase of solution ionic strength. The absorption band of the HA ultraviolet spectrum occurred red shift and the absorption intensity increased with the increase of solution ionic strength.And the HA E3 / E4 value and ionic strength had significant positive correlation. The absorption band of the HA ultraviolet spectrum happened with red shift with the increase of adding the concentrations of Cu2 ＋or Cd2 ＋.