CAJ | 학술논문

采用浸渍法制备了不同粒径的活性炭负载的Pt催化剂,并运用扫描电镜、N2吸附-脱附、透射电镜和X射线衍射对催化剂进行了表征.结果表明,当活性炭载体的粒径从253.2μm下降至9.3μm时,其表面积或孔体积变化不大,Pt颗粒高度分散于载体表面,平均粒径为2.8～5.5 nm.这些高度分散的Pt催化剂在非碱性条件下的甘油氧化反应中表现出较高的活性,且随着载体粒径的减小而明显提升.其中粒径为9.3 μm的活性碳负载的Pt催化剂上,游离的甘油酸收率达到47.6％,且催化剂可以重复使用.
채용침지법제비료불동립경적활성탄부재적Pt최화제,병운용소묘전경、N2흡부-탈부、투사전경화X사선연사대최화제진행료표정.결과표명,당활성탄재체적립경종253.2μm하강지9.3μm시,기표면적혹공체적변화불대,Pt과립고도분산우재체표면,평균립경위2.8～5.5 nm.저사고도분산적Pt최화제재비감성조건하적감유양화반응중표현출교고적활성,차수착재체립경적감소이명현제승.기중립경위9.3 μm적활성탄부재적Pt최화제상,유리적감유산수솔체도47.6％,차최화제가이중복사용.
Recent progress in the selective oxidation of biodiesel glycerol in aqueous solution by Au,Pt and alloy catalysts was reviewed.A series of Pt catalysts on different sized carbon supports were prepared and characterized by scanning electron microscopy,N2 adsorption,transmission electron microscopy,and X-ray powder diffraction.The average particle size of the carbon supports was decreased from 253.2 to 9.3 μm by ball milling,but their surface area and pore volume were only slightly changed.Pt was highly dispersed on these different sized carbon supports with an average particle size between 2.8-5.0 nm.Glycerol oxidation was catalyzed by these highly dispersed Pt catalysts in a base-free aqueous solution.The activity of the Pt catalysts increased with decreasing particle size of the carbon support,which was attributed to the higher accessibility of reactants to the Pt nanoparticles.The best yield of glyceric acid reached 46.7％ and the catalyst was stable during six recycles.