Dyeing with Hydrotalcite Hybrid Nanoclays and Disperse, Basic and Direct Dyes

Textile effluents are among the most polluting industrial effluents in the world. Textile finishing processes, especially dyeing, discharge large quantities of waste that is difficult to treat, such as dyes. By recovering this material from the water, in addition to cleaning and the possibility of reusing the water, there is the opportunity to reuse this waste as a raw material for dyeing different textile substrates. One of the lines of reuse is the use of hybrid nanoclays obtained from the adsorption of dyes, which allow dye baths to be made for textile substrates. This study analyses how, through the use of the nanoadsorbent hydrotalcite, dyes classified by their charge as anionic, cationic and non-ionic can be adsorbed and recovered for successful reuse in new dye baths. The obtained hybrids were characterised by X-ray diffraction and infrared spectroscopy. In addition, the colour was analysed by spectrophotometer in the UV-VIS range. The dyes made on cotton, polyester and acrylic fabrics are subjected to different colour degradation tests to assess their viability as final products, using reflection spectroscopy to measure the colour attribute before and after the tests, showing results consistent with those of a conventional dye.

Automated summary

Textile effluents, especially from dyeing processes, are highly polluting and difficult to treat. This study explores the possibility of reusing the waste, such as dyes, by recovering them from water and using them as raw materials for new dye baths. Hybrid nanoclays obtained from dye adsorption were used in the study, and their effectiveness in adsorbing anionic, cationic, and non-ionic dyes was analyzed. The results showed that the adsorbed dyes can be successfully reused in new dyeing processes, and the color degradation tests on different textile substrates yielded consistent results with conventional dyes.