Sustainable approach for the treatment of dye-containing wastewater - a critical review

In the world's rapidly expanding economy, textile industries are recognized as a substantial contributor to economic growth, but they are one of the most significant polluting industrial sectors. Dye-contaminated water sources can pose serious public health concerns, including toxicity, mutagenicity, and carcinogenicity among other adverse health effects. Despite a limited understanding of efficacious decolorization methodologies, the pursuit of a sustainable strategy for the treatment of a wide spectrum of dyes remains a formidable challenge. This article conducted an exhaustive review of extant literature pertaining to diverse physical, chemical, biological, and hybrid processes with the aim of ascertaining their efficacy. It also elucidates the advantages and disadvantages, cost considerations, as well as scalability impediments of the treatment methodologies, thereby facilitating the identification of optimal strategies for establishing techno-economically efficient processes in the sustainable handling of these effluents. The hybrid configuration exhibited superior efficiency and was documented to surmount the limitations and constraints inherent to individual techniques. The study also revealed that most of the proven and established dye removal techniques share a common limitation viz., the generation of secondary pollution (i.e., sludge generation, toxic intermediates, etc.) to the ecosystem.