Structural evolution of maize stalk/char particles during pyrolysis.
The structural evolution characteristics of maize stalk/char particles during pyrolysis were investigated. The char was prepared by pyrolyzing at temperatures ranging from 200 to 900 degrees C. Maize stalk and chars were characterized by thermogravimetric analysis, ultimate analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), helium density measurement and N(2) adsorption/desorption method. The char yield decreased rapidly with increasing temperature until 400 degrees C. As temperature increased, the char became progressively more aromatic and carbonaceous. The hydroxyl, aliphatic C-H, carbonyl and olefinic C=C groups were lost at high temperatures. Below 500 degrees C, the removal of volatile matter made pore opening. High temperatures led to the occurrence of softening, melting, fusing and carbon structural ordering. The aromatization process started at approximately 350 degrees C and continued to higher temperatures. The shrinkage of carbon structure occurred above 500 degrees C, which was concurrent with the aromatization process.
Fu
Peng
P
State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, PR China. fupengsklcc@gmail.com
Hu
Song
S
Sun
Lushi
L
Xiang
Jun
J
Yang
Tao
T
Zhang
Anchao
A
Zhang
Junying
J
D018533:Biomass; D004055:Differential Thermal Analysis; D006371:Helium / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D052638:Particulate Matter / Q000737:chemistry*; D016062:Porosity; D013499:Surface Properties; D013696:Temperature; D013818:Thermogravimetry; D003313:Zea mays / Q000737:chemistry*
D052638:Particulate Matter; D006371:Helium