Preparation and Evaluation of Sodium Carboxymethylcellulose from Sugarcane Bagasse for Applications in Coal-Water Slurry

A study on the feasibility of preparing cellulose from sugarcane bagasse, by means of chemical procedures including acid hydrolysis and alkaline treatment was conducted. The extracted purified cellulose was further used to prepare a cost-effective additive via alkalization and etherification for Coal-water slurry (CWS). The degree of substitute (DS) and intrinsic viscosity of the prepared sodium carboxymethyl cellulose (SCMC1) were determined and its structure was also characterized by means of FT-IR and TGA, with another sample of SCMC2 produced from microcrystalline cellulose and a commercial SCMC3 as references. Results showed SCMC1 had a DS of 0.857 which was 32.7% and 44.7% higher than SCMC2 and SCMC3, respectively. The higher intrinsic viscosity of SCMC1 indicated it had a higher molecular mass. The SCMC samples were used as additives to prepare CWS of which the rheological behavior and static stability were measured to evaluate their applied performances. The data showed that CWS with SCMC1 had a lower apparent viscosity and higher static stability than others, which was due to the higher DS and higher molecular mass of SCMC1. For SCMC1 could provide stronger electrostatic repulsive forces and steric repulsive forces between the coal particles via adsorption.