Open AccessSuperposition of Acid Concentration and Temperature at Production of Nanocrystalline Cellulose Particles
Publication year - 2018
Publication title -
journal of chemistry: education research and practice
Language(s) - English
Resource type - Journals
ISSN - 2578-7365
DOI - 10.33140/jcerp/02/01/07
Subject(s) - hydrolysis , sulfuric acid , crystallinity , cellulose , degree of polymerization , chemical engineering , degree (music) , nanocrystalline material , materials science , yield (engineering) , carbonization , chemistry , polymerization , polymer , inorganic chemistry , organic chemistry , nanotechnology , composite material , adsorption , physics , acoustics , engineering
Relationship between concentration of sulfuric acid (C) and temperature (T) required for the cellulose hydrolysisto prepare nanocrystalline cellulose particles (NCP has been studied in this paper. The experiments showed thatthere is a linear C and T superposition exists, namely: C= Co – n T. The higher the acid concentration, the lower thehydrolysis temperature should be used, and vice versa. The minimum level of acid concentration that can be usedfor production of CNP is 40 wt. % at optimal temperature of 80oC. If temperature or acid concentration is lower,there is a tendency to form of microparticles. On the other hand, at higher hydrolysis temperatures, carbonized CNPwith decreased yield are obtained. The rod-like crystalline nanoparticles of cellulose produced at optimal hydrolysisconditions (C=40 wt. %, T=80oC) have average sizes of 150 x 15 nm, degree of crystallinity of 75-77% and degreeof polymerization of 130-150. The nanoparticles form stable colloidal dispersions in water due to Brownian motionand negativeZeta potential imparting to these particles the mutual electrostatic repulsion. Estimated calculationshave also shown that decrease in the concentration of sulfuric acid from 60 to 40 wt. % at production of CNP iseconomically advantageous despite increase in hydrolysis temperature from 45 to 80oC.