改性介孔分子筛Zr-MCM-41对纤维素热裂解的影响  

Effect of Modified Mesoporous Molecular Sieve Zr-MCM-41 on Pyrolysis of Cellulose

作　　者：罗海彬 宋志杰 吴锦胜 张波 杨昌炎[1,2,3] 丁一刚[1,2] LUO Haibin;SONG Zhijie;WU Jinsheng;ZHANG BO;YANG Changyan;DING Yigang(School of Chemical Engineering and Pharmacy,Wuhan Institute of TechnoIogy,Wuhan 430205,China;Key Laboratory of Green Chemical Process(Wuhan Institute of Technology),Ministry of Education,Wuhan 430205,China;Key Laboratory of Preparation and Application of Catalytic Materials in Hubei Province(Huanggang Normal College),Huanggang 438000,China)

机构地区：[1]武汉工程大学化工与制药学院,湖北武汉430205 [2]绿色化工过程教育部重点实验室(武汉工程大学),湖北武汉430205 [3]催化材料制备及应用湖北省重点实验室(黄冈师范学院),湖北黄冈438000

出　　处：《武汉工程大学学报》2019年第1期40-45,共6页Journal of Wuhan Institute of Technology

基　　金：武汉工程大学校长基金(20170602)

摘　　要：采用溶胶凝胶法制备并筛选出对纤维素裂解催化效果最佳的改性介孔分子筛Zr-MCM-41。通过比表面积测定(BET)可知,Zr-MCM-41(nSi:nZr为100∶1、75∶1、50∶1)具有886～1157 m2/g的比表面积、3.21～4.04 nm的平均孔径、0.58～0.94 m L/g孔容。通过扫描电子显微镜-能谱(SEM-EDX)表征证实掺杂金属Zr质量分数在0.79～1.75%之间,可知其已成功负载到分子筛孔道和骨架上。将制备的介孔分子筛应用于纤维素的催化热裂解。裂解气相色谱质谱联用(Py-GC-MS)的结果表明:分子筛Zr-MCM-41在纤维素的热裂解过程中促进大分子化合物(如脱水糖)的降解,使其二次裂解反应和开环反应加剧,反应主要促进呋喃类化合物的生成,如糠醛和5-羟甲基糠醛。以糠醛作为目标产物时,nSi:nZr为50的Zr-MCM-41催化效果最佳,裂解产物中糠醛含量是无催化剂条件下的12.7倍。Modified mesoporous molecular sieves of Zr-MCM-41 were prepared by sol-gel method and screenedin the catalytic pyrolysis of cellulose.Brunauer-Emmett-Teller(BET)characterization showed that Zr-MCM-41(Si/Zi mole ratio of 100∶1,75∶1,50∶1)had a specific surface area of 886-1157 m2/g,an average porediameter of 3.21-4.04 nm,and a pore volume of 0.58-0.94 mL/g.It was confirmed by scanning electronmicroscopy and energy-dispersive X-ray(SEM-EDX)characterization that Zr was successfully loaded onto themolecular sieve pores and the skeleton,and the mass fraction of the doped metal Zr was between 0.79%and1.75%.The Zr-MCM-41 was used as the catalyst for pyrolysis of cellulose.The results of pyrolysis-gaschromatography-mass spectrometry(Py-GC-MS)show that molecular sieves of Zr-MCM-41 promote thedegradation of macromolecular compounds(such as anhydrosugars),and the secondary cracking reaction andring-opening reaction of anhydrosugars were intensified.The reactions mainly promote the formation of furancompounds such as furfural and 5-hydroxymethylfurfural.When furfural is the target product,Zr-MCM-41 withthe Si/Zr mole ratio of 50 shows the best catalytic activity,and the furfural content in pyrolytic products is 12.7times that of the catalyst-free condition.

关 键 词：纤维素 Zr-MCM-41 催化热裂解 裂解气相色谱质谱联用 糠醛 

分 类 号：TQ352.2[化学工程]