【作者】 赵小玲；

【导师】 郭人民；

【作者基本信息】 西北大学 ， 化学工艺， 2003， 硕士

【摘要】 本文介绍了纳米氧化铝的性质、用途、国内外研究现状及制备方法。讨论了液相法制备纳米粉体的理论基础，着重对前驱体制备全过程的防团聚机理进行了深入的理论分析。运用微波干燥的原理分析了对纳米氧化物进行微波干燥的可行性和优越性。论述了对纳米氧化铝进行表面改性的必要性和可行性。 本文对以氧化铝和碳酸钠为原料，采用直接沉淀法制备纳米氧化铝以及对纳米氧化铝进行表面改性工艺进行了较为系统的深入研究。在纳米氧化铝制备实验部分，首先设计了单因素试验对纳米氧化铝制备工艺进行了研究，探索了各个因素对纳米氧化铝制备的影响，然后以正交试验法筛选出制备过程的优化工艺条件。在改性试验部分，用单因素试验和正交试验筛选出了月桂酸钠改性的优化工艺条件；且以不同的工艺路线用三乙醇胺进行了改性研究，优选出了较佳的改性工艺路线。 试验结果表明： (1)采用两段微波干燥的方式对反应沉淀物进行干燥，可极大地提高干燥速率和能量利用效率，对液相法制备纳米粉体过程是一种新的有效的干燥方式。 (2)以氯化铝和碳酸钠为原料，采用直接沉淀法制备纳米氧化铝的工艺是可行的。直接沉淀法制备纳米氧化铝的优化工艺条件为：反应时间25min；反应温度40℃；碳酸钠浓度1.0M；氯化铝浓度0.4M；优化混合方式；煅烧温度500℃；煅烧时间1.5h。在此工艺条件下所得粒子的平均粒径8.7nm。 (3)纳米氧化铝经月桂酸钠处理可以得到表面亲油化的粒子，优化改性工艺条件为：改性温度30℃；改性pH=4；改性浓度3.0g/L；改性时间70min。在此条件下经改性后的产品的亲油化度为0.53。月桂酸钠与纳米氧化铝发生键合。 (4)以机械化学改性方法用三乙醇胺改性纳米氧化铝，可以得到能良好分散于乙醇的纳米氧化铝。三乙醇胺与纳米氧化铝发生键合。更多还原

【Abstract】 The properties, applications and research situation, and preparation method ofnanometer alumina at home and abroad has been presented in this paper. The theoreticalfoundation of nanometer particles of liquid-phase precipitation reaction was reviewed;especially theoretical analysis of preventing agglomeration mechanism in preparing nanometer particles was focused on. Furthermore, the feasibility and superiority of microwave drying method to prepare nanometer oxide has been analyzed based on the principle of microwave drying theory. In addition, the necessity and possibility of surface modification of nanometer alumina has been discussed.The process of both preparation of nanometer alumina in direct precipitation method(DPM) using sodium carbonate and aluminum chloride as materials and its surface modification has been deeply investigated. In the experimental section for preparation of nanometer alumina, a series of single-factor experiments has been firstly designed to do research on the preparation technology of nanometer alumina in order to study the effect of different factors in nanometer alumina preparation process; then the optimal preparation conditions have been obtained through multi-factor orthogonal experiment. On the other hand, in the experimental section for surface modification of nanometer alumina, both the mono-factor and multi-factor orthogonal method have been used to achieve selection of optimal surface modification processing conditions as sodium laurate was chosen as the modifying addition. Different surface modification technologies have also been practiced with triethanolamine to get an optimum process course.The experimental results are shown the following as follows:(1) Using a two-part microwave-drying method to dry nanometer alumina can significantly improve the drying rate and the energy utilization efficiency. It is a new efficient way to dry nanometer oxide.(2)The process of preparing nanometer alumina using the direct precipitation method with sodium carbonate and aluminum chloride as materials is possible. The optimal process conditions for preparation of nanometer alumina are: the reaction time is 25 min, the reaction temperature is 40 , and the concentration of sodium carbonate and that of aluminum chloride are 1.0 mol/1 and 0.4 mol/1, respectively; The optimum drop style was chosen; The calcination temperature and time are 500℃ and 1.5h. Under this optimal condition mentioned above, the average diameter of the nanometer alumina is 8.7nm.(3) Nanometer alumina turns to hydrophobic after surface modification with sodium laurate. The optimum conditions of surface modification are: temperature is 30℃ , the pH is 4, the concentration of modifying agent is 3.0g/L; modification time is 70min. The hydrophobic is about 0.53 under the above processing condition.(4) Nanometer alumina can be well dispersed in ethanol through modification with triethanolamine in mechanical chemical modification method. A new bond was produced between nanometer alumina and triethanolamine.更多还原