Extraction of Lignin from Agro-Waste Coir Fiber by Mild Alkali Treatment: A Statistical Approach for Process Optimization through Response Surface Methodology

Abstract

Lignin, a biomass with a wide range of applications, can be produced from agro-industrial waste, which can contributes to a reduction in the costs of production as well as the pollution load from the environment. The lignin content in coconut coir fiber is fairly high (40-45%) compared to other biomass. In current study, lignin is extracted from coconut coir fiber using a mildly alkaline solution and moist heat under pressure in an autoclave. Three factors were taken into consideration while designing the experiments: the variation in NaOH concentration, the variation in time and the variation in temperature. The optimal lignin extraction of 305.9742 mg/100 mL was achieved at 107 ºC and a heating time of 130 min by using a central composite design (CCD) of the response surface methodology (RSM).