Regulation Of Acid-base Sites On CeO₂ Surface And Study On The Catalytic Hydrogen Transfer Of Furfural To Furfuryl Alcohol

Finding alternatives to fossil fuels and reducing our dependency on them are essential steps in finding solutions to the numerous environmental problems caused by global warming.Furfural is an important biomass derivative.Its major product,furfuryl alcohol,is a greener alternative to fossil resources because it can be used to make a variety of high-valued compounds and fuel additives.Currently,the catalyst in the technology system for converting furfural to furfuryl alcohol is poisonous,uses hydrogen as well as other high-risk,high-cost ingredients,and does not adhere to the low-carbon idea.Nowadays,it is challenging to identify a method to convert furfural into furfuryl alcohol that is both environmentally friendly and efficient.As a result of recent developments in liquid-phase catalytic hydrogen transfer（CTH）hydrogenation,it is now possible to directly transfer hydrogen from small liquid molecules（such as methanol,isopropanol,formic acid,etc.）to furfural molecules in order to make furfuryl alcohol.It is regarded as a very promising hydrogenation technique and has generated a lot of interest.In this article,we investigate the hydrogenation of furfural to furfuryl alcohol by CTH using a range of nano-ceria materials as catalysts.The following are the primary contents:（1）By using the soft template self-assembly approach,a novel nanofibrous ceria catalytic material（Ce O₂-F）was created.Furfural was directly converted into furfuryl alcohol by hydrogen transfer at 180°C and 1 MPa N₂pressure using isopropanol as the hydrogen source.The conversion of furfural reached 99%and the reaction’s selectivity reached 88%after 6 hours of reaction.In-depth analyses of the changes of acid-base sites on the surface of fibrous cerium oxide catalysts were conducted using XPS,CO₂-and NH₃-TPD characterization methods.（2）The sol-gel method was utilized to synthesize an inorganic-organic composite cerium oxide modified with carboxylate.Ce O₂-C nanoparticles with a diameter of around 2 nm and a specific surface area of up to 200 m²g^-1were produced after calcination at 300°C.The catalyst is a Ce O₂material containing C=O and C-O functional groups,according to evidence from XRD,FT-IR,and XPS.The CO₂-and NH₃-TPD tests revealed that the composite particles’number of basic sites rose by more than three times when compared to the fibrous ceria catalytic materials that had（3）previously been developed.It was discovered that employing Ce O₂-C nanoparticles as a hydrogen transfer hydrogenation catalyst,the conversion of furfural could reach 99%in under 1 hour at 180°C and 1 MPa N₂pressure.