Abstract

The world’s second largest water consumer is the textile industry. Up to 20 % of global industrial water pollution is produced from textile industry [1]. Water is a common liquid medium in textile production, it is used for removing impurities, dyeing, applying finishing agents or for steam production. Only a small amount of used water is vaporized during individual technological operations. The most of applied water in colorization technology is discharged as wastewater. This wastewater typically contains high COD (Chemical Oxygen Demand) and BOD (Biochemical Oxygen Demand) contamination, high amount of total dissolved salts, exhibits high pH and elevated temperature. Wastewater from textile processes is usually highly colored. Effective wastewater treatment with subsequent recycling reduces the amount of consumed water and quantities of discharged pollutants.

This article deals with wastewater recycling based on removal of dissolved organics after reactive dyeing of cotton fabrics. Typically, it is necessary to use the sodium chloride solution to ensure good dye migration into the fiber. Almost all used sodium chloride remains in the wastewater. This article presents research focused on decolorization of wastewater by precipitation of dissolved anionic dyes applying ionic liquid and final treatment by active carbon. This combined decontamination method produces decolorized brine applicable for subsequent dye bath preparation [2].

Keywords:Textile wastewater; Ionic liquid; Reactive dyeing; Cotton