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Transparent bamboo (TB) is an attractive biomass‐derived material. However, the interrelation between process parameter and product performance is not clear yet. In this paper, the process parameter during preparation is optimized by orthogonal experiment and finally TB with excellent optical and mechanical properties is successfully prepared. Among the investigated runs, TB‐12 exhibited the best performance with high transmittance (89.2%), good color difference property (L: 76.8, A: 5.4, B: 5.9), and excellent tensile strength (119.3 MPa). As the final aim of this work, deeper insight into the interrelation between process parameters and product performance is also investigated by response surface methodology (RSM) and linear analysis method. Based on the analysis result, it can be concluded that i) X2‐ temperature is the most influential factor to the lignin content (p‐value = 0.0532) during delignification process; ii) during resin impregnation process, lignin content has strong correlation with optical property: for example, transmittance (R2 = 0.90423) and A value (R2 = 0.92073), but has no significant correlation with mechanical property (tensile strength: R2 = 0.04186). Moreover, it is found that the correlation between lignin content and transmittance can be preliminarily predicted before the experimental start. This hypothesis has been validated by importing experimental data of previous references into the model. This work demonstrates a deep analysis of TB preparation process and may provide the referenced gist for parameter selection. [ABSTRACT FROM AUTHOR]

Aldol condensation of cyclopentanone is an attractive reaction for bio‐jet fuel production. KOH is an efficient homogeneous catalyst for aldol condensation but suffering the problem of separation. In this paper, a heterogeneous catalyst, diatomite stabilized KOH (KOH/diatomite) was prepared in a simple way (dry‐mixed impregnation process), and exhibited good activity (overall yield: 85.0 %) and reusability. To clarify the support effect of diatomite, KOH/SiO2 catalyst was also prepared. According to characterizations of these two catalysts, we suggest that the excellent catalytic activity of KOH/diatomite can be attributed to the formation of K−O−Si bond. In addition, the impurity elements existed in diatomite (e. g. CaO, Na2O, Al2O3) and higher BET surface areas may also benefit to this reaction. This study provides a new possibility for converting homogeneous catalyst (KOH) to heterogeneous catalyst (KOH/diatomite). In this way, KOH/diatomite performed excellent catalytic activity and exhibited stable reusability, which can avoid the problem of separation and pollution. [ABSTRACT FROM AUTHOR]

For the first time, waste-seashell-derived CaO catalysts were used as high-performance solid base catalysts for cyclopentanone self-condensation, which is an important reaction in bio-jet fuel or perfume precursor synthesis. Among the investigated seashell-derived catalysts, Scapharca Broughtonii-derived CaO catalyst (S-shell-750) exhibited the highest dimer yield (92.1%), which was comparable with commercial CaO (88.2%). The activity sequence of different catalysts was consistent with the CaO purity sequence and contact angle sequence. X-ray diffraction (XRD) results showed that CaCO3 in waste shell were completely converted to CaO after calcination at 750 °C or above for 4 h. CO2 temperature-programmed desorption (CO2-TPD) results indicate that both the amount and strength of base sites increase significantly when the calcination temperature climbs to 750 °C. Therefore, we can attribute the excellent performance of S-shell-750/850/950 catalysts to the higher CaO content, relatively low hydrophilicity, and stronger acidity and basicity of this catalyst. This study developed a new route for waste shell utilization in bio-derived ketone aldol condensation. [ABSTRACT FROM AUTHOR]

When using a combination of pre‐extraction and chemical pulping, a high yield of sugar recovery and minimal negative effect on the subsequent pulping step are expected. In this work, the P factor was utilized to investigate the effect of auto‐hydrolysis severity on sugar recovery, removal of the main component, and impact on the kraft pulping of acacia wood chips. Using a P factor of 235, 84.34% of the polysaccharides in 14.05 g L−1 of dissolved sugars could be obtained. In addition, the soluble sugars were easily separated with a recovery yield of 3.54 g ·L−1 and Mw of 4,690 g mol−1 by direct precipitation using organic solvents. However, a maximum of 22.14 g L−1 of dissolved sugars was obtained with approximately 72.53% polysaccharides and Mw of 2,198 g mol−1 for a P factor of 601. Moreover, nearly 50% of the degraded carbohydrates remained in the auto‐hydrolyzed wood chips. The decrease in the mass of pentosan, holocellulose, and klason lignin was 62, 30, and 8.76%, respectively. With intensifying severity, the screened yield and viscosity of pulps decreased markedly, whileas the Kappa number increased. No significant differences were observed in the morphology of the resultant fibers. Moreover, there was a decrease in the physical strength of the pulps due to the loss of the intrinsic strength of the pulp fibers, which in turn resulted from the cellulose damage. The combustion performance of the resultant pulping black liquor is improved due to the higher lignin content. [ABSTRACT FROM AUTHOR]