Using biodegradable organic salt for cotton garment dyeing to reduce effluent pollution

The replacement of inorganic salt and alkali in the reactive dyeing of cotton textiles with organic biodegradable compound has been explored in recent years. We report the use of organic salt, tetra sodium salt of glutamic acid diacetic acid (GLDA-Na-4) in the batchwise dyeing of cotton garment as an exhausting and fixing agent. The reactive dye, CI Reactive Black 5 was selected for the present study. The results revealed that the maximum K/S value of 25.5 and fixation of 90.74% was obtained using GLDA-Na-4 at laboratory scale experiments. Furthermore, the effluent samples test results demonstrated considerably reduced total dissolved solids (TDS) and chemical oxygen demand (COD) contents with GLDA-Na-4 in comparison to the inorganic chemicals. The colourfastness to light, rubbing and washing have demonstrated similar ratings with GLDA-Na-4 and inorganic chemicals. The tensile strength of samples was enhanced by using GLDA-Na-4.

Automated summary

The replacement of inorganic salt and alkali in reactive dyeing of cotton textiles with organic biodegradable compounds has been studied. This study investigated the use of tetra sodium salt of glutamic acid diacetic acid (GLDA-Na-4) as an exhausting and fixing agent in the batchwise dyeing of cotton garments. The results showed that GLDA-Na-4 achieved a maximum K/S value of 25.5 and fixation rate of 90.74% in laboratory scale experiments. Additionally, the use of GLDA-Na-4 led to significantly reduced total dissolved solids (TDS) and chemical oxygen demand (COD) in the effluent samples compared to inorganic chemicals. The colorfastness and tensile strength of the dyed samples were similar to those achieved with inorganic chemicals.