玉米芯磁性碳基固体酸的制备及其催化木糖制备糠醛OA北大核心

To improve the utilization value of corn cob and realize the recycling of catalysts,magnetic carbon-based solid acid catalyst(Ni-SO3C)were successfully prepared by impregnation,carbonation,and sulfonation method using hydrolyzed corn cob residue as the raw material of carbon precursor.The physicochemical properties and structure of the catalyst were characterized using scanning electron microscopy(SEM),Fourier-transform infrared spectroscopy(FT-IR),X-ray diffraction(XRD),N2 adsorption-desorption,elemental analysis,Boehm's assay,X-ray photoelectron spectroscopy(XPS),and pyridine infrared.The catalyst's performance for converting xylose to furfural was also investigated.The results showed that the specific surface area and pore volume of the catalyst were 235.1 m2/g and 0.3 cm3/g,respectively,with a total acid density of 8.9 mmol/g as well as the presence of Bronsted and Lewis acid sites in the catalyst;the analysis by FT-IR showed that the Ni-SO3 C catalyst at 1 205 and 1 032 cm-1 O=S=O and—SO3 characteristic absorption peaks appeared in the Ni-SO3C catalyst,confirming the successful introduction of sulfonic acid groups;XRD showed the presence of characteristic diffraction peaks of nickel in the catalyst(44.3°,52.0°,and 76.2°),indicating that the nickel crystalline phase remained stable after sulfonation;XPS further verified that elemental sulfur existed in the form of sulfonate and sulfhydryl groups,and C1s and O1s spectra showed a significant increase in the content of oxygen-containing functional groups,enhancing the sulfur content of the catalyst.Under the conditions of water/dichloromethane(DCM)volume ratio of 6∶4,xylose mass concentration of 20 g/L,and xylose-to-catalyst mass ratio of 1∶1,the reaction was carried out for 60 min at 200 ℃,the furfural yield could reach up to 67.2％,and the furfural yield remained at 52.0％after 5 cycles.The Ni-SO3C-catalyzed preparation of furfural from Ni-SO3C-catalyzed corn kernel hydrolysis liquid had a better effect,and the furfural yield reached up to 66.4％.