产品粒度的影响
(中南大学 化学化工学院，长沙410083)
摘 要: 选用谷氨酸作为种分添加剂，在初始浓度ρ(Na2O)为150 g/L，初始苛性比αk0为1.42，温度为75 ℃，搅拌速度为160 r/min，晶种系数Ks为0.25的实验条件下，研究添加剂用量对铝酸钠溶液分解率和产品粒度的影响。结果表明：谷氨酸在一定浓度范围内能提高铝酸钠溶液分解率，低浓度时添加效果最佳；添加浓度为3×10−3 mol/L，反应进行到2 h时产品粒度得到细化，其它条件下产品粒度均得到粗化。结果表明：谷氨酸是有效的铝酸钠溶液种分添加剂。
关键字: 谷氨酸；铝酸钠溶液；种分；分解率；粒度分布
sodium aluminate solution
（School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China）
Abstract:Glutamic acid was adopted as additive in seeded precipitation process on the condition of ρ(Na2O) 150 g/L, initial αK 1.42, temperature 75 ℃, agitation speed 160 r/min and Ks 0.25. The effect of dosage on the decomposition ratio of sodium aluminate solutions and particle size distribution(PSD) of gibbsite was investigated. Experimental results indicate that glutamic acid can increase the decomposition ratio of sodium aluminate at lower concentration. The particle size of gibbsite product is reduced when the additive concentration is 3×10−3 mol/L at 2 h. The particle size is enlarged under other conditions. All the results show that glutamic acid is an effective additive for the seeded precipitation of sodium aluminate solution.
Key words: glutamic acid; sodium aluminate solution; seeded precipitation; decomposition rate; particle size distribution
