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Alpha-pinene is an important forest chemical resource, and the cis-pinane obtained by its hydrogenation reaction is used in spices, medicine, and other industries. A hollow nanospheric material with amphiphilic properties in a two-sided structure was prepared, with a nitrogen-doped carbon layer towards the inside and mesoporous silica in the outer layer of the nanospheres. The amphiphilic catalyst with non-precious nickel as the active component was synthesized by loading nickel onto the nanospheres using a simple impregnation method and applied to the aqueous phase hydrogenation reaction of α-pinene. The mesoporous structure of the catalyst shortened the mass transfer distance and thus reduced the mass transfer resistance. The nitrogen atoms doped in the carbon matrix provided anchor points for stabilizing the metal nanoparticles; the hydrophilic outer surface and hydrophobic hollow cavity enabled the catalyst to be well dispersed in water while still enriching the organic matter in aqueous solution. The effect of various reaction conditions on the catalytic reaction was investigated. The catalysts showed excellent activity and good stability, suggesting a new green and efficient method for more effective exploitation of biomass pine resin resources, and providing a reference for expanding the application of non-precious metal catalysts.

Several representative ionic liquids (ILs) were synthesized, and [Emim]OAc was chosen as environment-friendly solvent for enzymatic in situ saccharification in view of its biocompatibility with both natural and microcrystalline cellulose, as well as its enzymatic activity. With the microwave pretreatment of natural and microcrystalline cellulose, directly enhancing the in situ enzymatic saccharification, the rate was compared versus an untreated control by the detection of dinitrosalicylic acid (DNS). It is suggested that the molecular structure of cellulose in the process of pretreatment was changed, e.g. intramolecular hydrogen bonds were broken (detected by FT-IR), and the crystallinity (monitored by SEM and XRD) changed significantly from a crystalline to an amorphous pattern. These changes of cellulose led to an increase of reducing sugar conversion during cellulose enzymatic hydrolysis. [ABSTRACT FROM AUTHOR]