Extraction and characterization of guinea corn plant extract for mordant assisted dyed cotton fabric

Synthetic dyes have been discovered to be harmful to the human body and also to the environment as they are non-biodegradable. Hence, recent researches and discoveries on the use of natural plants such as Guinea corn leaves (Sorghum bicolour) as colourants in the textile industry. Dye from Sorghum bicolour was extracted using both distilled water and ethanol (90:10 v/v) and (10:90 v/v) respectively. Dye standardization was done using UV-Visble spectrophotometer in the range between 375 nm to 800 nm. The wavelength of maximum absorbance was gotten to be 575 nm and used in determining the absorbance at various concentrations (100, 200, 300, 400, 500, 600, and 700 mg/L).

The physico-chemical properties such as pH level, dye colour, percentage yield and solubility of the aqueous extracted dye was found to be 6.86, reddish brown in colour, 15.66% and dissolves freely in warm water while that of the ethanolic extracted dye was found to be 6.68, wine in colour, 21.48% and partially soluble in warm water. Characterization of the dye was done using Fourier Transform Infrared Spectroscopy, Ultraviolet-Visible Spectroscopy, Scanning Electron Microscope, Brunauer-Emmett-Teller’s theory, Thermogravimetric Analysis and Differential Thermal Analysis. The extracted dye was then used in dyeing pre and post mordant white cotton fabric using both alum and magnesium sulphate as mordants fabrics which improve the colour shades and fastness properties of the dyes thereby enhancing their aesthetic value.