The catalytic transformation of furfuryl alcohol and hexose into value-added chemicals have been investigated with a series of polymer-based catalysts including poly(styrenesulfonic acid) (PSS), graphite oxide-doped poly(styrenesulfonic acid) (PSS-GO), and graphite-doped poly(styrenesulfonic acid) (PSS-C). It is found that the selective conversion of furfuryl alcohol to methyl levulinate (MLE) was successfully performed with PSS as the catalyst, in which a 96.4% yield is attained in methanol solvent. Moreover, the efficient dehydration of d -fructose to produce 5-hydroxymethylfurfural (HMF) has also been achieved using PSS-GO as the catalyst, where a 76.5% yield of HMF was obtained in N -methylpyrrodinone solvent. The effects of reaction temperature, time and solvent were investigated. Furthermore, the used catalysts have been respectively characterized by XRD, TG, FTIR, SEM and TEM techniques to reveal the physical properties and structures of these polymeric catalytic materials.
Haonan Qu,Bingyi Liu,Guohua Gao,Yiming Ma,Yanmei Zhou,Hua Zhou,Li Li,Yonghong Li,Shengjian Liu
Levulinic acid (LA) is a versatile key building block in the conversion of carbohydrates and it is an important basic chemical with various potential uses. MIL-100(Fe) loading with insoluble lysine functionalized phosphotungstic acid (Lys-PM 2 ) as heterogeneous catalysts have been synthesized for the conversion of glucose to LA in water. The optimized yield of LA is obtained by using Lys-PM 2 to catalyze glucose conversion is comparable to the majority of effective catalysts. The highest yield of LA (57.9%) is obtained at 150 °C for 9 h with 100 mg glucose and 25 mg Lys-PM 2 , since the Brønsted acidity and Lewis acidity of Lys-PM 2 . And the catalyst is able to recycle at least four times. It demonstrates the potential of Lys-PM 2 for the conversion of biomass.
The precise synthesis of multifunctional poly(ionic liquid)s (MFPILs) featuring basic sites, mesoporous channels, and hydrophobicity continues to be a substantial challenge. Moreover, the directional conversion of lignite to monocyclic arenes (MCAs) is highly attractive but particularly challenging on account of its geometrical complexity and chemical inertness. The efficiency of lignite directional conversion to MCAs over solid bases is substantially decreased by the presence of water molecules leading to the deactivation and leaching of basic sites. Herein, the novel solid bases, i.e. , MFPILs with dibasic sites, unique hydrophobicity , and abundant mesoporous channels, were successfully fabricated by a radical multicomponent cross-linked copolymerization for the first time. Even more excitedly, the resulting MFPILs were demonstrated to be very efficient for directional catalytic hydroconversion of extraction residue from Dahuangshan lignite (DL ER ) into MCAs with 32.3 wt% yield, which is by far the highest value reported for lignite-derived MCAs by solid bases under similar conditions. The synergistic catalysis, i.e. , hydrophobic microenvironment, mesoporous confinement, and synergistic effect of dibasic sites, for active hydrogen transfer of DL ER conversion into MCAs over MFPILs is confirmed by characterization methods. The work not merely sheds substantial light on developing the novel solid bases, but also exhibits a potentially powerful catalyzing strategy to synthesize MCAs.