复合萃取剂脱除废水中的活性红K-7B染料

Removal of C.I. reactive red 4 from wastewater by composite extractant

为了实现印染废水部分脱色,为后续生化处理提供有利条件,研究构建了三辛胺(TOA)-二(2-乙基己基)磷酸酯(P204)-磺化煤油(SK)复合萃取剂萃取废水中活性红K-7B染料,考察了萃取时间、水油比、p H和洗脱剂等对脱色效果的影响.结果表明:在TOA、P204和SK的体积比为18∶12∶70、水油比为5∶1、活性红K-7B染料初始质量浓度为1 g/L、p H值为3,萃取时间10 min和室温等条件下,该复合萃取剂对活性红K-7B染料的萃取率(脱色率)达到87.6%的同时,获得了较高的染料溶质分配比32.5;以15%Na OH作为洗脱剂,可实现复合萃取剂的洗脱,其回收率为94.3%.

In order to achieve partial decolorization of dyeing wastewater and provide beneficial conditions to subsequent biochemial process, a novel composite extractant consisting of trioctylamine（TOA） and di-（2-ethylhexyl）phosphoric acid（P204） with sulfonated kerosene（SK） as diluent, was adopted for the removal of reactive red 4 from dyeing wastewater. The influence of contact time, phase ratio, p H and stripping agent on the decoloration effects was systematically investigated. The results showed the dye removal and its distribution ratio（D） within the composite extractant successively reached 87.6% and 32.5 under optimal conditions those which were the extractant concentration 18%（v/v） TOA, 12%（v/v） P204 and 70%（v/v） SK at a phase ratio（A/O） of 5 ∶ 1, initial dye concentration of 1 g/L, p H of 3, extraction time of 10 min and room temperature. Furthermore, the reused organic phase could be obtained after the stripping of dye with 15% Na OH solution and its recovery efficiency was 94.3%.