Evaluation of sulfuric acid-pretreated biomass-derived biochar characteristics and its diazinon adsorption mechanism.

In this study, hemicellulose was mostly removed from biomass (larch and oak) using a sulfuric acid pretreatment. Biochar was then prepared from raw and pretreated biomass using a carbonization process. Biochar derived from pretreated biomass had an aromatic and graphitized structure, and functional groups were observed on the surface. The specific surface area was higher for biochar obtained from pretreated biomass than biochar derived from raw biomass. The biochar obtained from pretreated biomass contained a greater number of micropores than biochar derived from raw biomass. The diazinon removal rate was the highest for biochar that was obtained from pretreated biomass when 10% of the biochar was added to the soil. As a result of the adsorption of diazinon onto the biochar obtained from pretreated biomass, the R2 value of the Langmuir isotherm was higher than that of the Freundlich's R2.

Effect of torrefied biomass on hydrophobicity and mechanical properties of polylactic acid composite.

In this study, the physicochemical properties of torrefied biomass (larch and yellow poplar) were investigated based on torrefaction temperature. The effect of torrefied biomass on the hydrophobicity and mechanical properties of a polylactic acid (PLA) composites was evaluated. Hemicellulose was removed from the biomass during torrefaction, whereas the cellulose and lignin contents increased slightly. The color of the biomass changed from brown to black. The grindability of the torrefied biomass improved as the torrefaction temperature increased, which contributed to the production of fine particles (>100 mesh). A PLA composite was prepared using torrefied biomass (10 %) and polylactic acid. At 280 °C, water contact angle was the highest, regardless of the particle size and biomass species. Tensile strength of the PLA composite was slightly lower than that of PLA alone, regardless of the particle size of torrefied biomass. Nevertheless, the strength increased with the torrefaction temperature, except for larch with a relatively large particle size (<100 mesh). The tensile strength of the control was 68.0 MPa, whereas that of the torrefied biomass ranged from 61.1 to 65.8 MPa.

Structural characterization of the lignin-carbohydrate complex in biomass pretreated with Fenton oxidation and hydrothermal treatment and consequences on enzymatic hydrolysis efficiency.

In this study, lignin-carbohydrate complexes (LCCs) were isolated from biomass (raw and pretreated) to investigate the structural changes in biomass pretreated by Fenton oxidation and hydrothermal treatment, and their effect on enzymatic hydrolysis. The composition and structure of the LCCs fractions were investigated via carbohydrate analysis, XRD, FT-IR, and 2D HSQC NMR. The biomass degradation rate of yellow poplar and larch during Fenton oxidation and hydrothermal treatment was approximately 30%. Most of the hemicellulose was degraded during pretreatment, while xylan remained in the yellow poplar, and galactan, mannan, and xylan remained in the larch. The fractional yield of glucan-rich LCC (LCC1) in the yellow poplar (raw and pretreated biomass) was high, while that of glucomannan-rich LCC (LCC3) in larch was higher than the yield yellow poplar. Phenyl glycoside, γ-ester, and benzyl ether linkages were observed in the LCCs of yellow poplar, while phenyl glycoside and γ-ester were detected in those of larch. Following pretreatment, the frequencies of ß-ß', ß-5, and γ-ester in the LCCs of larch were found to be higher than in those of yellow poplar. The efficiencies of enzymatic hydrolysis for the pretreated yellow poplar and larch were 93.53% and 26.23%, respectively. These finding indicated that the ß-ß', ß-5, and γ-ester linkages included in the pretreated biomass affected the efficiency of enzymatic hydrolysis.