Comparative study of lignin and sodium lignosulfonate extracted from irradiated and non-irradiated sawdust wastes

Abstract

Recent technologies in the production of chemicals and bio-material products are focusing on lignocellulosic biomass resources since it is the world's most abundant economical material, recyclable, sustainable, low cost, as well as highly renewable natural resources. This biomass refers to agricultural wastes such as woody plants (soft and hardwood). Lignin is extracted from these agro-wastes using chemical methods and ionizing radiation. The outcome of employing gamma radiation as a pretreatment step prior chemical treatment on the duration for alkaline, acid, and production of sodium lignosulfonate (NaLS) was examined. The structure of the produced NaLS was verified utilizing Nuclear magnetic resonance (1H-NMR, 13C-NMR) and Liquid chromatography–mass spectrometry (LC–MS). A comparison between the physicochemical properties of sodium lignosulfonate extracted from both non-irradiated and irradiated sawdust waste was studied using FTIR, XRD, EDX and TGA. The degree of sulfonation of the produced NaLS was determined utilizing the potentiometric titration method. The findings demonstrated that gamma exposure pretreatment step reduces the time of alkaline, acid, and sulfonation processes as well as a higher yield percentage and degree of sulfonation.