Investigating coagulation behavior of chitosan with different Al species dual-coagulants in dye wastewater treatment
Investigating coagulation behavior of chitosan with different Al species dual-coagulants in dye wastewater treatment
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DOI：
10.1016/j.jtice.2017.06.052
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发表时间：
2017-09
影响因子：
5.7
通讯作者：
Wenyu Wang;Q. Yue;Ruihua Li;Wen Song;B. Gao;Xue Shen
中科院分区：
文献类型：
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作者：
Wenyu Wang;Q. Yue;Ruihua Li;Wen Song;B. Gao;Xue Shen
以壳聚糖（CS）为助凝剂，采用不同铝形态（Ala/Alb/Alc）对分散黄（DY）废水进行处理。考察了混凝剂投加量和初始pH值对脱色、絮体结构和再生的影响。结果表明，壳聚糖的加入能显著提高絮凝效果，这是由于絮凝剂与铝种-染料聚集体之间存在较强的相互作用。氨基质子化后的CS可与DY废水中的偶氮键和甲基发生联合收割机结合。此外，随着CS的加入，特别是在较低的Al剂量下，会产生较大的絮体。实验结果表明，溶液初始pH值对水解产物中铝的形态和壳聚糖的电荷有影响，进而影响脱色效率和絮体性质。pH值在6.0 ~ 7.0时，脱色率较高。Ala及其复合混凝剂在碱性条件下形成较大的絮体，Alb/Alc及其复合混凝剂在酸性条件下形成较大的絮体。在凝结的水中，强度和再生的值也增加CS剂量，由于引入桥接和电荷中和。
In this study, chitosan (CS) was used as a coagulant aid with different Al species (Ala/Alb/Alc) to treat disperse yellow (DY) wastewater. The effects of coagulant dosages and initial pH on color removal, floc structure and regrowth were investigated. Results showed that the efficiency could be significantly improved with the addition of CS, due to the strong interaction between flocculants and Al species–dye aggregates. CS with the protonation of amino groups could combine with the azo bond and methyl of DY wastewater. Moreover, larger flocs would be generated as CS was added, especially at lower Al dosages. Based on the experimental results of this research, the initial solution pH had an impact on the hydrolysates of Al species and charge of CS, and further influence the color removal efficiency and floc properties. The color removal efficiency was relatively large at pH 6.0–7.0. The bigger flocs were formed under alkaline condition for Alaand its dual-coagulant, and under acidic condition for Alb/Alcand the corresponding dual-coagulants, respectively. In coagulated water, the values of strength and regrowth also increased as CS was dosed, due to the introduction of bridging and charge neutralization.