Utilization of Ash from Thermal Decomposition of Rice Straw as a Natural Dye

Abstract

Indonesia is among the largest countries in global rice production. Annual generation of rice straw of about 20 million tons were reported. It is therefore, utilization of rice straw as natural dye is considered to minimize pollutant problem. Rice straw composed of 48.7% carbon that generate black color. In this research, natural dyes of rice straw ash were applied in cotton and rayon fabrics, followed by mordanting using lime, alum, and ferrous sulphate. The color intensity and color fastness of cotton and rayon fabrics dyed using rice straw ash extract was investigated. It was found that the system using ferrous sulphate mordant produced the lightest color; alum mordant treatment produced a darker color while the darkest color was provided by system using lime as mordant.