Extraction of natural dye from black tea waste for cotton dyeing application

Abstract

An investigation has been made to predict the efficiency of ultrasound-assisted extraction methods in natural dye recovery from black tea waste for cotton dying applications. The black tea waste was obtained from Universiti Malaysia Kelantan (UMK) cafeteria. The ultrasonic-assisted extraction was done for different volume of solvents (100 ml, 200 ml, 300 ml, and 400 ml). The solvent used in this research work is petroleum ether. Result shows that 300 ml of solvent volume gives highest yield of extract. Then, the extraction is further proceeding with different extraction time (2 hours, 4 hours, 6 hours and 8 hours) before followed to extraction without ultrasonic. The result shows that 8 hours of extraction time is more effective in extracting black tea waste. For cotton dyeing application, it has demonstrated an excellent dyeing result at 40 C°-50 C° with a minimal amount of metal mordant (0.5 %). The experimental data were analysed using the colorimeter to determine the specification of colours, and Fourier transform infrared spectroscopy (FT-IR) to confirm the components in black tea waste. Results from this work mainly can be applied in the textile industry.