Evolution of Waster Cotton Fiber Hydro-Char Physicochemical Structure during Hydrothermal Carbonation

Abstract

Abstract：In order to study the hydrothermal behavior of cotton fiber, the carbonization process and structural evolution of discarded cotton fiber (WCF) under hydrothermal conditions were discussed use microcrystalline cellulose (MCC) and glucose as model compounds. The results showed that high temperature was beneficial to the hydrolysis of discarded cotton fiber, and the yield of the sugar was 4.5% which was lower than that of MCC 6.51%.WFC and MCC are carbonized in 240~260 ℃ and 220~240 ℃ respectively, while the carbonation temperature of glucose is lower than 220 ℃. The quality ratio of C/O in WCF and glucose hydrothermal products is 5.79 and 5.85 respectively; three kinds of hydrothermal carbonization products have similar crystal structure and oxygen-containing functional groups, and the WCF carbonization products contain a lot of irregular particles while the main products of glucose carbonization are 0.5 μm carbon microspheres (CMCC). The results show that glucose is an important intermediate product of WCF hydrolysis carbonation, and there are two main paths of cotton fiber hydrothermal carbonization: some cotton fibers are completely hydrolyzed into glucose and the nucleation is formed, and then the carbon microspheres are grown; for the other part, the glucose ring of the polysaccharide oligosaccharide formed by the incomplete hydrolysis of cotton fiber in the hydrothermal environment of high temperature and pressure breaks, then forms the particulate matters.

A Review on Micro- to Nanocellulose Biopolymer Scaffold Forming for Tissue Engineering Applications

“…Table 2 shows the comparison between the obtained particle size and preparation technique. [49], (c,d) the surface of micro-microcrystalline cellulose from the cotton stalk [50], (e,f) microcellulose particles of cotton, adapted [51]. Modification of hydrolysis conditions such as temperature, time, and acid concentration has been reported to have a significant impact on the degree of polymerisation of MCC.…”

“… Scanning electron microscope (SEM) images of different forms of microcellulose materials. ( a , b ) Surface of micro-fibrillated cellulose from the bleached cotton stalk [ 49 ], ( c , d ) the surface of micro-microcrystalline cellulose from the cotton stalk [ 50 ], ( e , f ) microcellulose particles of cotton, adapted [ 51 ]. …”