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Mechanistic pathways of catalytic hydrodeoxygenation determine the portfolios of biomass-derived platform chemicals. Bifunctional catalysts involving active metals on acidic supports are known to c...

Ionic liquids have been widely studied as effective reaction media for the conversion of glucose or cellulose to 5-hydroxymethhylfurfural (5-HMF). However, the recovery of 5-HMF from ionic liquids, typically carried out by extraction, has been encountered with very low extraction efficiency, which limited the reusability of the solvents. Through this work, based on the model biphasic system that consists of 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) as the ionic liquid phase and methyl isobutyl ketone (MIBK) as the extractant phase, the dominant force that suppresses the extraction efficiency of 5-HMF was identified as being the strong hydrogen bonding between 5-HMF and [BMIM]Cl. Solvent mediation with functional promoters have been established as a new strategy to shift this force, resulting in improved extraction efficiency of 5-HMF from the ionic liquid. For example, with ethanol as a promoter, the distribution coefficient of 5-HMF was about 10 times higher than that without a promoter.

The SO3H-functionalized ionic liquids were synthesized by using pyridine and 1,4-butane or 1,3-propane sulfone as the source and characterized by NMR and time-of-flight mass spectrometry. The acidity of the ionic liquids determined by the Hammett method is almost the same as that of a conventional acid, such as H2SO4. The catalytic performance of ionic liquids for the tert-butylation of p-cresol with tert-butanol was evaluated; by using the ionic liquids as catalysts at the optimum reaction conditions, 79% of the p-cresol conversion and 92% of the selectivity to 2-tert-butyl-p-cresol can be obtained. The spent ionic liquid can be recovered and recycled. The possible mechanism for this reaction system was discussed based on the reaction results and the ab initio calculation results.

Removal of C2H4 from a CO2 stream is very important in ultrapurification of CO2 for its application and utilization. However, it is difficult to remove C2H4 completely from a CO2 stream via conventional cryogenic distillation because the volatility of C2H4 is similar to that of CO2. Another choice is the catalytic combustion method, but it is an energy-inefficient process, especially when it is coupled with the cryogenic distillation. Selective adsorption for removing C2H4 might be a promising alternative. A great effort has been made in C2H4/C2H6 separation and recovery of C2H4. There were, however, few reports about the removal of a trace amount of C2H4 from a CO2 stream. In this study, the AgNO3-modified NaY and HY zeolites are prepared and their adsorption performances are evaluated via a series of experiments of fixed-bed adsorption, frontal chromatographic adsorption, and temperature-programmed desorption (TPD). The structure of the sliver salt after being impregnated onto the supports has been char...

Removal of C2H4 from a CO2 stream is very important in ultrapurification of CO2 for its application and utilization. However, it is difficult to remove C2H4 completely from a CO2 stream via conventional cryogenic distillation because the volatility of C2H4 is similar to that of CO2. Another choice is the catalytic combustion method, but it is an energy-inefficient process, especially when it is coupled with the cryogenic distillation. Selective adsorption for removing C2H4 might be a promising alternative one. A great effort has been made in olefin/paraffin separation and recovery of olefin. There are, however, few reports about the removal of a trace of C2H4 from a CO2 stream. In this study, ab initio calculations have been conducted to screen the potential adsorbents. We found that AgNO3 exhibits a much higher adsorption affinity for C2H4 through a π-complexation interaction, indicating that the AgNO3-modified zeolite might be a promising adsorbent. Furthermore, the AgNO3-modified NaY zeolite was prepar...