Direct Contact Membrane Distillation Applied to Colored Reactive or Disperse Dye Solutions

Abstract

The influence of dye class and chromogen groups of dyeing wastewaters composed by reactive or disperse dyes with different colors on direct contact membrane distillation (DCMD) was investigated. The state-of-the-art shows that disperse dyes and different dye colors are not studied in DCMD and the application of DCMD for dyeing wastewater treatment is limited to a few publications. High color rejection was obtained and water was recovered at the permeate side for feed solutions containing reactive or disperse dye. Influence of chromogen groups (colors) was not observed, whereas the class dye was decisive for the process performance. Reactive dyes showed higher mean permeate flux due to the repulsion between their anionic groups and the negative surface of the membrane. Partial wetting of larger pores allowed the passage of small disperse dye molecules, reducing color rejection.

Novel Triple-Layer HIPS/SBR/PP Nanofibrous Membranes for Robust DCMD Desalination

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PFOM fillers embedded PVDF/cellulose dual-layered membranes with hydrophobic–hydrophilic channels for desalination via direct contact membrane distillation process

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