Development of Solid Superbase by Controlled Oxygen Anion Generation

1.以10~(-15)×10~(-5)×10~(-2)~(-2)K~(++)离子的表面密度将金属盐分散在载体上，在惰性气氛中于适当温度下活化，制得了高碱性固体催化剂。金属盐可以是第1族元素的硝酸盐或碳酸盐。有效的载体是氧化铝和氧化锆，二氧化硅和二氧化钛无效。该催化剂对顺丁烯、3甲基L烯、1，2-丙二烯和α-蒎烯异构化反应以及环己二烯异构化/脱氢制苯、环己烯和氢气以及柠檬烯异构化/脱氢制对伞花烃3均表现出较高的活性。从TPD和红外/拉曼光谱可以看出，在高表面密度时，金属盐既以凝聚相存在，在低表面密度时又以离子分离相存在。前者在接近其自身分解温度的温度下分解，而后者在远低于其分解温度的温度下分解，并归因于可能脱离其反阳离子的阴离子分解。基本性质的产生与阴离子的分解密切相关。NO_3^-分解为NO_2+O^-，CO_2分解为CO_2+O^&lt；推测是释放出的氧负离子(S)构成基本中心。推测在氧化铝和氧化锆的情况下，可以将释放的氧离子与金属氧化物载体的阴离子区分开来，而在二氧化钛载体上则不能。X射线衍射仪证实，金属盐在二氧化硅载体上只能以团聚相的形式存在。载体的有效性可能是释放出的氧离子与载体的识别能力的差异。在高温下碱度的丧失可以归因于两个氧阴离子的平整。

1. A highly basic solid catalyst was obtained by dispersing metal salts over supports at the surface density of 10 - 15 x 10^<18> K^+ ions m^<-2> and activating them at proper temperature in an inert atmosphere. Metal salts can be the nitrate or carbonate of group 1 elements. Effective supports were alumina and zirconia; silica and titania are ineffective.2. The catalyst exhibited high activity in the isomerizations of cis-but-2-ene, 3-methyl-but-l-ene, propa-1,2-diene and α-pinene, and the isomerization/dehydrogenation of cyclohexadiene to benzene, cyclohexene and hydrogen, and of limonene to p-cymene3. From TPD and IR/Raman spectroscopy, it was found that mounted metal salts exist as both an agglomerated phase when the surface density is high and an ion-separated phase when the surface density is low. The former decomposes at the temperature close to its own decomposition temperature, while the latter decomposes far below the decomposition temperature and was attributed to the anion decomposition that may be free from its counter cation.4. The generation of basic property closely relates to the anion decomposition. NO_3^- decomposes to NO_2 + O^- and CO_2 decomposes to CO_2 + O^<2->. It is suspected that the liberated oxygen anion(s) constitutes basic centers.5. It is speculated that liberated oxygen anions can be discriminated from the anions of metal oxide supports in case of alumina and zirconia, while can not on titania support. Metal salts can only exist as agglomerated phase on silica support that was confirmed by XRD. Effectiveness of support could be the difference of the discrimination ability of liberated oxygen anions from those of supports. The loss of basicity at elevated temperatures could be attributed to the leveling of both oxygen anions.