针对反应结晶过程铝氧水合物混晶造成产品粒度分布宽泛、杂质含量高等问题，本项目基于两步成核机制与团簇理论，以铝-有机碱水溶液体系制备铝氧水合物新过程为对象，以“结构解析-量化调控-构效关系”研究为主线，提出以微结构定向诱导为核心的混晶度调控新方法。借助先进的原位监测技术、结构精细分辨手段与分子模拟方法，开展铝酸根单体基元-介稳中间体-晶核的多尺度结构研究，特别聚焦主导尺度关键结构即介稳中间体的精准解析。借助FBRM等手段研究晶种、超声波对环境相介稳区宽度连续精确定量调控规律，获取成核能垒等动力学量化参数，揭示晶型改性剂、超声波与介稳中间体的微观作用机制。研究典型杂质相间迁移行为与分配规律，探明高纯晶体杂质选择性定向分离机制。量化混晶附聚体抗磨损、耐碱性、机械细化后粒度分布与球形度等参数，获得产品构效关系。旨在建立介稳区宽度与介尺度中间体协同调控晶体成核新方法，支撑铝氧水合物高值产品的制备。

Wide particle size distribution and high impurity content occurred in aluminate reaction crystallization process is difficult to control. Based on two-step nucleation mechanism and cluster theory, a new method for the control of mixed crystallinity with the orientation-induced regulation of metastable intermediates is proposed in the new organic alkali media. The evolution process of unit aluminates-metastable intermediates-nuclei is investigated by means of DFT simulation and fine time-space resolution structure identification techniques. In particular, special attention is paid to the accurate analysis of mesoscale metastable intermediate structures, which are the key structures at the dominant scale. Seeds and microwave are used to continuously and accurately quantify the width of metastable zone width, and the kinetic parameters such as nucleation energy barrier are obtained by means of FBRM. The microscopic mechanism of interaction between crystal modifier, active seed crystal, ultrasonic wave and metastable intermediate is revealed. The migration behavior and distribution law of typical impurity are studied, and the selective orientation separation mechanism of high purity crystal impurities is investigated. The parameters, such as wear resistance, alkali resistance, particle size distribution and sphericity after mechanical refinement, are quantified to obtain the structure-function relationship. In order to support the preparation of high valued alumina hydrate products, a new method of synergistic regulation of mixed crystallinity by mesoscale intermediates and metastable zone width was proposed.