Nano Crystalline Alumina：Characterization and Catalytic Reactions

• Main Authors: chih yü Lee, 李之瑜
• Other Authors: 柯安男
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/20338392509837593171

碩士 === 東海大學 === 化學系 === 94 === The Beckmann rearrangement of gaseous cyclohexanone -oxime(CHO) to produce ε-caprolactam(ε-C) and isopropylation of benzene with 2-propanol have been studied using a fixed bed, integral reactor. γ-Al2O3（nano）and γ-Al2O3 were utilized as catalysts. These materials were characterized with X-ray powder diffraction, scanning and transmission electron microscopy, physisorption, and temperature programmed desorption so as to obtain catalyst properties, i.e., structure, surface area, pore shape and size, as well as the amount and the strength of acid sites .The partical size of γ-Al2O3（nano）was much smaller than γ-Al2O3 as also evidenced by its X-ray line broadening. Forthermore , γ-Al2O3（nano）owns larger amount and higher strength of acid sites . In the reaction of CHO, γ-Al2O3（nano）catalyst exhibits better catalytic activity than γ-Al2O3 catalyst due to its stronger acidity and larger surface area. The CHO conversion increases with the reaction temperature and the contact time, where the ε-C selectivity exhibits the opposite trend. Both the catalyst stability and the ε-C selectivity greatly enhance by using ethanol and n-hexanol as solvents due to the production of water vapor via dehydration. In the reaction of benzene with propanol , both the catalytic activity and the isopropyl benzene selectivity enhance with a decrease of catalyst particle size and an increase of mole ratio （B/IPA）and reaction temperature.