粉煤灰对酸性染料的吸附脱色研究

Study on adsorption decoloration of acid dyes by fly ash

以燃煤废弃物粉煤灰作为吸附剂,对酸性蓝193与酸性黑1进行吸附脱色,研究了影响脱色的因素.结果表明:粉煤灰10g/L时,2只酸性染料的吸附在初始30min内基本达到平衡,高温改性粉煤灰的吸附脱色性能明显提高.2只染料在酸性条件下的脱色率高于碱性条件,脱色效率最佳.随染液初始质量浓度增大,染液的脱色率不断降低,但粉煤灰吸附量却不断增大.粉煤灰及改性粉煤灰对2只染料的恒温吸附脱色数据符合Langmuir和Freundlich恒温吸附方程,吸附参数表明:粉煤灰对水溶性酸性染料的吸附过程容易进行,粉煤灰及改性粉煤灰对2只染料的吸附动力学过程为准二级吸附。

The fly ash from coal combustion waste was used as adsorbent to discolor Acid Blue 193 and Acid Black 1 from aqueous solution. The factors affected the decoloration were studied. The results showed that when the concentration of fly ash was 10 g/L, the adsorption of the two dyes could reach balance in the first 30 min, and the adsorption ability of fly ash modified in high temperature was improved obviously. In acid condition, the color removal of both dyes were higher than in base, the decoloration efficiency was the best. The color removal decreased with increasing of initial concentration of dye solution, however, the adsorption capacity of fly ash increased with increasing of initial concentration of dye solution. The thermostatic adsorption decoloration data of fly ash and modified fly ash on both dyes accorded with Langmuir and Freundlich thermostatic adsorption equation. The sorption parameters showed that the adsorption of fly ash on water soluble acid dyes easy, and the adsorption kinetic of fly ash and modified fly ash on the two dyes accorded with the pseudo-second-order model.