磁性氧化铁/SO2-4生物质基固体酸催化剂合成及特性

利用聚乙二醇法和亚硫酸钠法制备磁性氧化铁颗粒,通过负载法合成磁性氧化铁/SO2-4生物质基固体酸催化剂,从磁性氧化铁颗粒的不同制备方法入手分析催化剂的合成及特性.以表面酸量、磁响应性能及催化水解微晶纤维素所得还原糖得率(DNS法)为指标考察催化剂的活性;利用X射线衍射仪(XRD)、傅里叶红外光谱仪(FT-IR)、拉曼光谱仪(Raman)、扫描电子显微镜(SEM)、振动样品磁强计(VSM)表征催化剂结构.结果表明:磁性氧化铁颗粒的合成方法对制备催化剂活性和结构有较大影响.其中,用亚硫酸钠法制备磁性颗粒合成的催化剂表面酸量大(1.13mmol/g),还原糖得率高达30%,且制备工艺周期适中(2970min),催化剂的碳含量较高,负载的磁性氧化铁颗粒较多且与碳材料结合程度高,比表面积较大,孔道结构丰富;通过VSM分析可知:聚乙二醇法合成的催化剂为铁磁性材料,亚硫酸钠法合成的催化剂为亚铁磁性材料.

Synthesis and Properties of Magnetic Ferric Oxide/SO2-4 Biomass-based Solid Acid Catalyst

Two kinds of magnetic ferric oxide particles were prepared through glycol and sodium sulfite methods.Magnetic ferric oxide/SO2-4 biomass-base solid acid catalysts were synthesized via loading the magnetic ferric oxide particles into the sulfuric acid treated biomass-base precursor.The catalyst activities,such as surface acid amount,magnetic response properties and reducing sugar yield (DNS method) from catalytic hydrolyzed micro-crystalline cellulose were evaluated.The structures of the catalyst were characterized by XRD,FT-IR,Raman,SEM and VSM.The results showed that the catalyst activity and structure are quite different from different synthesis methods.Compared with the catalyst prepared from PEG method,the acid density for 1.13mmol/g,reducing sugar yield for 30%,carbon content of the catalyst by the sodium sulfite method are much higher,and the cycle of preparation process is moderate(2970min).At the same time,the magnetic Ferric Oxide load particles amount is also higher,the specific surface area is larger,channel structure is richer.VSM analysis showed that the catalyst prepared by polyethylene glycol method was ferromagnetic material,and the catalyst prepared by sodium sulfite was ferrous magnetic materials.