Synthesis of carboxymethyl cellulose from waste of cotton ginning industry

The aim of present work was to isolate cellulose from cotton gin waste (CGW) and synthesis of carboxymethyl cellulose (CMC) from it. Scoured and bleached CGW was used to investigate the effects of temperature, reaction time, acid-base concentration on the physiology of the resultant cellulose polymer. The isolated cellulose from CGW was converted to CMC by etherification using sodium monochloroacetic acid and different sodium hydroxide (NaOH) concentrations (5-40 g/100 mL) were tested to get high quality product. The optimum condition for carboxymethylation was found to be 20 g/100 mL NaOH which provided the highest viscosity and degree of substitution (DS = 0.874). Isolated cellulose and CMC were characterized using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). FT-IR analysis revealed that the produced cellulose was of very good quality. Furthermore, X-ray diffraction (XRD) analysis spotlighted crystalline nature of cellulose. SEM images showed rough structure of cellulose while that of the CMC had a smooth surface. This optimized method will be tested at pilot scale in collaboration with local industry. (C) 2014 Elsevier Ltd. All rights reserved.