铝酸钠溶液种分过程中草酸钠结晶析出的行为

拜耳法氧化铝生产过程中，草酸钠在铝酸钠溶液晶种分解工序造成诸多负面影响.本文对种分过程草酸钠结晶析出的行为进行研究.用含草酸钠的合成和工业铝酸钠溶液分别进行分解实验，考察草酸钠对分解产物粒度和形貌的影响，并对草酸钠的结晶习性、草酸钠与氢氧化铝之间的相互作用规律进行探究.结果表明，草酸钠在氢氧化铝表面或颗粒间隙结晶析出，使氢氧化铝二次成核增加，并严重阻碍氢氧化铝的附聚，这是其造成产品氢氧化铝粒度细化的主要原因.

Behavior of sodium oxalate in seeded precipitation process of sodium aluminate solution

Sodium oxalate has negative effects on alumina produced by the Bayer process. The behavior of sodium oxalate in the seeded precipitation process of a sodium aluminate solution was investigated. The particle size and morphology of crystallization, as well as the crystal habit of sodium oxalate, and the interaction between sodium oxalate and gibbsite in synthetic or industrial sodium aluminate solutions were also investigated. The results show that sodium oxalate precipitates on the surface or gibbsite clearance, such that the secondary nucleation of gibbsite increases, and the agglomeration of gibbsite is seriously hindered. This is considered as the main cause of gibbsite refinement.