【作者】 李莉丽；

【导师】 刘全生；

【作者基本信息】 内蒙古工业大学 ， 应用化学， 2009， 硕士

【摘要】 本文主要进行OL和OMS结构多孔锰氧化物合成过程的优化,运用了XRD、BET和微反色谱等测试与表征技术,探讨了各种因素对OL和OMS结构多孔锰氧化物合成过程的影响。OL结构锰氧化物合成的研究结果表明,氧化还原法没有合成单一晶相的OL-1,所合成的样品中均有六方水锰矿晶相。当反应温度达到45℃时,继续提高温度对OL-1结构的影响很小;随着Mn²⁺/MnO₄^-的增加,六方水锰矿的晶相越来越好;当OH-/Me²⁺≥8时,碱量的继续增加对样品结晶度的影响不大,样品的化合价也趋于稳定;以KOH作为沉淀剂得到的样品结晶度不好,且比表面积较低;采用醋酸锰作为锰源要优于硫酸锰;Cu掺杂的锰氧化物没有六方水锰矿的晶相,并且Cu的分散度也较好;氧化法能够制得单一晶相的水钠锰矿。氧气法合成OL-1的关键因素是氧气通量,只有溶液中具有足够的的氧含量,即具有足够大氧气扩散推动力的情况下才能生成晶型完整的OL-1;当反应时间小于3h时,主要得到是黑锰矿,当反应时间达到5h时,才能够得到单一晶相OL-1;采用硝酸锰作为锰源要优于硫酸锰;是否加入H₂O₂对水钠锰矿的形成影响不大。OMS结构锰氧化物的研究结果表明,氧气法合成的布塞尔矿在酸性介质中、H₂O中、碱性介质中,均不能合成具有孔道结构的锰氧化物,但在碱性介质中晶化进一步优化了OL-1;离子交换中,只有Cu离子交换后的样品能够生成OMS-1结构锰氧化物,而Ca离子、Mg离子交换后的样品不能得到OMS-1,但得到了1nm矿相;在不同反应时间中,只有Mg的加入时间为0h时能够生成OMS-1结构锰氧化物。更多还原

【Abstract】 This paper focused on the optimization of OL and porous structure OMS synthesis processes and XRD, BET and Micro-Reactor-Chromatography were used to study effect of preparation factors on OL and OMS manganese oxides.For the manganese oxides of OL structure, the OL-1 phase was not the only phase detected in the samples and the Feitknechtite phase was also contained. when the synthesis temperature is higher than 45℃the temperature is not the main influence factor to prepare OL-1. The crystalline of Feitknechtite improve with Mn²⁺/MnO4- increasing and the best value in preparing the OL-1 manganese oxide is Mn²⁺/MnO4-=70.8/29.2. It is showed that KOH as the precipitator is not suitable to the formation of OL-1 structure and the specific surface area of samples. It is proved that manganese acetate as the source of Mn is better than manganese sulfate. The Feitknechtite phase disappeared when the Cu²⁺ was added in the solution. Purely OL-1 manganese oxide can be synthesized through oxidation style. The results showed that the flux of O2 is the pivotal factor for the synthesis of OL-1 manganese oxide. Only the solution with high oxygen content has enough oxygen diffusion force for formation of purely OL-1. Hausmanite is the main phase when the oxidation time is lesser than 3h, and pure OL-1 structure can be detected when it is more than 5h. Manganese nitrate as the starting material of Mn is better than manganese sulfate. The effect of H2O2 treatment after the layer manganese oxide is formatted is very small.Buserite synthesized by oxygen can not transformed into porous manganese oxide structure under the acidic reaction condition, H2O and alkaline, but under alkaline medium the crystallization of OL-1 is further optimized. Buserite transformed into OMS-1 structure after ion-exchanged with Cu ion, but buserite maintained after ion-exchanged with Mg and Ca ions. OMS-1 can be synthesized by oxygen when the Mg ion was added in the original solution.更多还原