產(chǎn)品粒度的影響
(中南大學(xué) 化學(xué)化工學(xué)院，長沙410083)
摘 要: 選用谷氨酸作為種分添加劑，在初始濃度ρ(Na2O)為150 g/L，初始苛性比αk0為1.42，溫度為75 ℃，攪拌速度為160 r/min，晶種系數(shù)Ks為0.25的實驗條件下，研究添加劑用量對鋁酸鈉溶液分解率和產(chǎn)品粒度的影響。結(jié)果表明：谷氨酸在一定濃度范圍內(nèi)能提高鋁酸鈉溶液分解率，低濃度時添加效果最佳；添加濃度為3×10−3 mol/L，反應(yīng)進(jìn)行到2 h時產(chǎn)品粒度得到細(xì)化，其它條件下產(chǎn)品粒度均得到粗化。結(jié)果表明：谷氨酸是有效的鋁酸鈉溶液種分添加劑。
關(guān)鍵字: 谷氨酸；鋁酸鈉溶液；種分；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
