This perspective highlights the catalytic characteristics and future prospects of nano-/hierarchical zeolites in gaseous phase and liquid phase reactions.

No abstract

Carbohydrates are expected to replacep etroleum and to become the base of industrial chemistry.C hirality is one particular area in which carbohydrates have as pecial potentiala dvantage over petroleum resources. Herein, we report ac atalytic approachf or thed irect production of d-tetroses [i.e., d-(À)erythrose and d-(+ +)-erythrulose] from d-hexoses through af ast retro-aldol process at 190 8Ct hat achieves ay ield of 46 %a nd completely retains the chiral centers in the final chiral synthon. The d-tetrose products were further converted into their derivatives, thereby accomplishing transfer of chirality from natural chiral hexoses to high-value-added chiral chemicals. Our results also suggest that the product distribution for the conversion of d-hexoses was determined by their isomerization and epimerization trends that competed with their corresponding retro-aldol condensation processes.

A clear and deep understanding of zeolite crystallization with the addition of organosilane is desirable for the reasonable design and preparation of hierarchical zeolites. Herein, the effects of different organosilanes on zeolite crystallization were systematically studied. It was found that organosilane plays the role of an inhibitor in the silanization-based zeolite preparation, and this inhibition effect was determined by its participation degree. An organosilane with a high participation degree can result in the prolongation of nucleation and growth periods of zeolite as well as the variation of product properties. More importantly, a dynamic participation pathway of organosilane is proposed, that is, the growth of zeolite is accompanied by the continuous removal of organosilane, leading to an increase of product crystallinity as well as the decrease of mesoporosity. This study gives a new insight into the role that organosilane plays in zeolite crystallization, which will help to direct the rational selection of organosilane and design of crystallization condition for the optimal synthesis of hierarchical zeolites.

No abstract

The aldose transformation process in borate-containing acidic phosphate buffer system is systematically studied under microwave irradiation.

A systematic hydrothermal pretreatment of corncob has been conducted with an aim to trace the content and property of lignin during the pretreatment process. The result showed that the lowest content of lignin was obtained under the following condition: water-solid ratio is 3:1,180 °C for 90min with 0.4g auxiliary medium. TG and FTIR analysis has been conducted to investigate the thermal stability and structure of lignin, and the result indicated that hydrothermal pretreatment influenced the thermal stability and structure of lignin extracted from corncob.

Waste water from enzymatic biodiesel technology (contained glycerol 5%) is treated as following: Firstly, waste water is filtered with a gauze, add KOH to PH=7~8, and filter to remove salt soap. Secondly, the processed liquid distil at 50°C in Rotary Evaporator vacuum to remove most of water and methanol, then concentrated solution use plinthic flocculants (mass ratio of 100:1), stirring at 70°C to eliminate colloid. Finally, at 180°C, 0.8 kPa to vacuum distil to collect glycerol of purity up to 90.43％.The glycerol react with acetic acid to get glycerol triacetate with phosphotungstic acid catalyst, toluene as water-carrying agent. Thus comes out the yield of more than 90％ glycerol triacetate in 6 hours.