化学絮凝过程中活性染料混合物的残余色度分布

Residual Color Profiles of Reactive Dyes Mixture during a Chemical Flocculation Process

以聚环氧氯丙烷二甲胺（PEPIDA）为絮凝剂，测量了化学絮凝过程中由活性黑（KN—B）和活性艳红（K-2BP）构成的二元混合染料模拟有色废水脱色过程中的残留色度分布．溶液残留色度与游离染料、结合态染料、粒子散射5个组分的浓度有关．在PEPIDA投加量不足的区间，KN-3R优先去除．在投加量过量的区间，样品中的残余色度主要来自重新稳定的染料＋PEPIDA配合物，粒子光散射也是降低脱色率的另一个原因，它引起1—4％的脱色率下降．根据残留色度分布曲线，得到KN—B和K-2BP与PEPIDA的结合常数分别为1．86×10^6．72×10^5L／mol．

Residual color profiles of a model color wastewater samples, prepared by the mixtures of Reactive Red K-2BP （K-2BP） and Reactive Black KN-B （KN-B）, during a chemical flocculation process by using poly（epicholorohydrin-diamine） （PEPIDA） were investigated. In the region of insufficient dosage of PEPIDA, K-3R was preferentially removed. The residual color is related to the concentration of two free dyes, two complexes of dye ＋ PEPIDA and fine flocs dispersed in solutions. In the over-dosed region, the residual color in the samples is mainly from the re-stabilized complexes of dye ＋ PEPIDA. The light scattered by the particles is another reason for the decrease ca. 1 - 4% in color removal efficiency. According to the residual color profiles, the binding constants for K-2BP and KN-B onto PEPIDA were estimated to be 1.86 × 10^6 L/mol and 6. 72 ×10^5 L/mol, respectively.