Construction of Functional Phenolic Resin and Carbon Hollow Spheres by Manipulating Structural Inhomogeneity.

Hollow carbonaceous spheres are extraordinarily attractive for their unique structural features and wide applications in various fields. Herein, a facile and effective synthesis methodology based on the extended Stöber process for construction of phenolic resin hollow spheres has been presented. Combined with a series of characterization techniques, the synthesis process was systematically investigated, and a possible synthesis mechanism was proposed. It is revealed that the structural inhomogeneity of the polymer product achieved by using dodecylamine and alkane is responsible for the formation of hollow architecture, which depends on spontaneous selective dissolution during the synthesis process. Different metal-doped carbonaceous hollow spheres can be obtained by introducing corresponding precursors into the synthetic system and meeting requirements of different application fields. This work presented a novel synthesis strategy of hollow carbonaceous spheres, which is significant for building a new platform of advanced functional carbon-based composites.

Optimization of furfural production from D-xylose with formic acid as catalyst in a reactive extraction system.

Furfural is one of the most promising platform chemicals derived from biomass. In this study, response surface methodology (RSM) was utilized to determine four important parameters including reaction temperature (170-210°C), formic acid concentration (5-25 g/L), o-nitrotoluene volume percentage (20-80 vt.%), and residence time (40-200 min). The maximum furfural yield of 74% and selectivity of 86% were achieved at 190°C for 20 g/L formic acid concentration and 75 vt.% o-nitrotoluene by 75 min. The high boiling solvent, o-nitrotoluene, was recommended as extraction solvent in a reactive extraction system to obtain high furfural yield and reduce furfural-solvent separation costs. Although the addition of halides to the xylose solutions enhanced the furfural yield and selectivity, the concentration of halides was not an important factor on the furfural yield and selectivity.

The optimization of formic acid hydrolysis of xylose in furfural production.

Formic acid, a byproduct of furfural process, can be an effective catalyst for dehydration of xylose into furfural. Due to the low corrosion resistance, easy to be separated and reused, there is a growing interest in the use of formic acid as catalyst. In this study, response surface methodology (RSM) was used to optimize the hydrolysis process in order to obtain high furfural yield and selectivity. Three important parameters, initial xylose concentration (40-120 g/L), temperature (170-190 °C), formic acid concentration (5-15 g/L) were optimized. The optimum initial xylose concentration, formic concentration, reaction temperature were 40 g/L, 10 g/L, and 180 °C, respectively. Under these conditions, the maximum furfural yield of 74% and selectivity of 78% were achieved.