Determination of Available Alumina, Active Alumina and Active Silicon in Gibbsite Bauxite by Inductively Coupled Plasma-Optical Emission Spectrometry with Microwave Digestion
-
摘要: 有效铝、活性硅是判定三水铝土矿质量的重要指标，这两项指标的测定通常采用微波消解电感耦合等离子体发射光谱法（ICP-OES）。该方法首先测定出消解试液中的铝（即有效铝），再将剩余的残渣酸化溶解，进而测定出硅（即活性硅）。然而，由于消解试液不易澄清和残渣酸溶不完全，往往导致结果的重现性较差。本文对此方法作一改进，将消解的试液酸化加热，以钴为内标，采用ICP-OES同时测定出溶液中的活性铝和活性硅，然后间接计算出溶液中的有效铝。方法精密度（RSD，n=13）小于3%，回收率为97.0%~102.6%，用国际标准物质验证的测定结果与标准值吻合。本方法解决了消解后的溶液不易澄清和剩余残渣酸溶不完全的问题，克服了基体效应和仪器波动对测定结果的影响，能同时测定出活性铝和活性硅，并且提出的活性铝的概念可应用于三水铝土矿的综合评价和氧化铝生产工艺的调整。Abstract: Available alumina and active silicon in gibbsite bauxite are important indicators for the quality of bauxite. These two components are commonly determined by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). In this method, available alumina in solution after digestion is determined first and active silicon is then determined after acid dissolution of the residue. However, because the solution is not easy to determine, and the residue cannot be digested completely, the results have poor reproducibility. By heating and acidifying the solution and taking Co as the internal standard, the conventional method can be improved upon. Active alumina and active silicon were simultaneously determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), and available alumina was quantified indirectly by calculation. The method precision (RSD) is greater than 3% (n=13) and the recoveries range from 97.0% to 102.6%. The results of international standard materials are consistent with the certified values. The proposed method solves the issues of the conventional method and improves the influence of the matrix effect and equipment drift on analytical results. This method can determine simultaneously active alumina and active silicon. The concept of active alumina can be used to comprehensively evaluate gibbsite bauxite and the adjustment of the production method of aluminum oxide.
-
-
表 1 NaOH加入量影响
Table 1. Effect of NaOH dosage
NaOH浓度
(g/L)有效铝Al2O3含量
(%)Al2O3溶出率
(%)活性硅SiO2含量
(%)30 23.58 60.48 0.53 45 33.31 85.43 0.67 55 35.02 89.82 0.65 65 35.47 90.97 0.67 80 35.41 90.82 0.64 90 35.65 91.43 0.68 100 35.62 91.36 0.65 
下载: 导出CSV
表 2 微波消解温度的影响
Table 2. Effect of microwave digestion temperature
测定项目 1#样品 2#样品 温度(℃) 120 140
150 175120 140
150 175有效铝Al2O3
含量(%)36.12 36.32
36.77 37.1334.33 35.96
35.90 35.81活性硅SiO2
含量(%)7.63 10.65
10.65 10.960.96 1.05
1.12 2.56
下载: 导出CSV
表 3 加盐酸后放置时间对澄清液中硅含量的影响
Table 3. Effect of placement time after adding hydrochloric acid on the content of silicon in supernatant liquid
测定项目 1#样品 2#样品 放置时间(h) 12 24
48 7212 24
48 72不加热SiO2含量
(%)5.04 5.60
5.82 5.881.32 1.50
1.68 1.76加热SiO2含量
(%)5.88 5.86
5.87 5.851.77 1.80
1.77 1.78
下载: 导出CSV
表 4 加标回收率实验
Table 4. Spiked recovery tests of the method
原浓度
(μg/mL)Al2O3含量(μg /mL) 原浓度
(μg/mL)SiO2含量(μg /mL) 加标量 加标后测量值 回收率
(%)加标量 加标后测量值 回收率
(%)20.82 10 30.62 98.0 11.26 10 21.08 98.3 20 40.86 100.2 20 31.29 100.2 30 50.11 97.6 57.94 20 78.18 101.2 2.06 2.0 4.11 102.6 50 106.45 97.0 4.0 6.13 101.8 100 158.00 100.1 6.0 7.94 98.0
下载: 导出CSV
表 5 方法精密度实验
Table 5. Precision tests of the method
样品编号 本实验方法 文献方法 有效铝Al2O3 活性硅SiO2 有效铝Al2O3 活性硅SiO2 平均值
(%)RSD
(%)平均值
(%)RSD
(%)平均值
(%)RSD
(%)平均值
(%)RSD
(%)1# 29.61 1.05 3.67 1.87 29.49 1.80 3.54 2.49 2# 36.96 1.69 10.65 1.51 37.03 2.64 10.47 1.88
下载: 导出CSV
表 6 方法准确度实验
Table 6. Accuracy tests of the method
国际标准物质编号 推荐值 实验方法 有效铝Al2O3
(%)活性硅SiO2
(%)有效铝Al2O3 活性硅SiO2 平均值
(%)相对误差
(%)平均值
(%)相对误差
(%)BXGO-1 59.33±0.53 0.516±0.012 59.38 0.08 0.52 0.54 BXPA-2 50.65±0.43 4.15±0.15 50.36 -0.57 4.14 -0.30 BXMG-2 45.47±0.37 1.879±0.082 45.08 -0.87 1.97 4.80 BXSP-1 40.00±0.31 7.84±0.26 40.32 0.79 7.71 -1.67 BXMG-3 33.20±0.30 0.754±0.062 33.02 -0.54 0.75 -0.07
下载: 导出CSV
-
[1] 艾光华, 刘俊星.低品位三水铝石型铝土矿选矿试验研究[J].中国矿业, 2011, 20(4):62-66. http://www.cnki.com.cn/Article/CJFDTOTAL-YSKS201102007.htm
Ai G H, Liu J X.Study on low Al-Si ratio gibbsite bauxite dressing pilot[J].China Mining Magazine, 2011, 20(4):62-66. http://www.cnki.com.cn/Article/CJFDTOTAL-YSKS201102007.htm
[2] 奥地利安东帕公司.铝钒土中有效铝和活性硅的测定[J].岩矿测试, 2007, 26(2):170-171. http://www.ykcs.ac.cn/ykcs/ch/reader/view_abstract.aspx?file_no=20070260&flag=1
Austrian Anton Parr Company.Determination of available alumina and reactive silicon in bauxite[J].Rock and Mineral Analysis, 2007, 26(2):170-171. http://www.ykcs.ac.cn/ykcs/ch/reader/view_abstract.aspx?file_no=20070260&flag=1
[3] 付高峰, 田福泉, 权昆.中低品位铝土矿石灰拜耳法溶出的研究[J].东北大学学报(自然科学版), 2005, 26(11):1093-1095. doi: 10.3321/j.issn:1005-3026.2005.11.020
Fu G F, Tian F Q, Quan K.Research on low grade bauxite lime Bayer process dissolution[J].Journal of Northeastern University (Natural Science), 2005, 26(11):1093-1095. doi: 10.3321/j.issn:1005-3026.2005.11.020
[4] 余新阳, 钟宏, 刘广义, 等.新型阳离子有机硅QAS222对铝硅矿物浮选行为的研究[J].非金属矿, 2010, 33(1):11-13. http://www.cnki.com.cn/Article/CJFDTOTAL-FJSK201001005.htm
Yu X Y, Zhong H, Liu G Y, et al.Research on relation of novel organosilicon cation surfactant QAS222 and aluminosilicate mineral flotation behaviors[J].Non-Metallic Mines, 2010, 33(1):11-13. http://www.cnki.com.cn/Article/CJFDTOTAL-FJSK201001005.htm
[5] 张国范, 卢毅屏, 欧乐明, 等.捕收剂RL在铝土矿浮选中的应用[J].中国有色金属学报, 2001, 11(4):712-715. http://www.cnki.com.cn/Article/CJFDTOTAL-ZYXZ200104036.htm
Zhang G F, Lu Y P, Ou L M, et al.A new collector RL for flotation of bauxite[J].The Chinese Journal of Nonferrous Metals, 2001, 11(4):712-715. http://www.cnki.com.cn/Article/CJFDTOTAL-ZYXZ200104036.htm
[6] 余新阳, 钟宏.阳离子反浮选脱硅捕收剂研究现状[J].轻金属, 2008(6):6-10. http://www.cnki.com.cn/Article/CJFDTOTAL-QJSS200806003.htm
Yu X Y, Zhong H.Current research status on cationic collector of reverse flotation desillication[J].Light Metal, 2008(6):6-10. http://www.cnki.com.cn/Article/CJFDTOTAL-QJSS200806003.htm
[7] 吴边华, 董洁.关于铝土矿浮选脱硅的综述[J].煤炭技术, 2008, 27(4):120-122. http://www.cnki.com.cn/Article/CJFDTOTAL-MTJS200804065.htm
Wu B H, Dong J.Overview of flotation for desilication of bauxite[J].Coal Technology, 2008, 27(4):120-122. http://www.cnki.com.cn/Article/CJFDTOTAL-MTJS200804065.htm
[8] 潘晓林, 于海燕, 涂赣峰, 等.石灰对三水铝石型铝土矿低温溶出行为的影响[J].东北大学学报(自然科学版), 2013, 34(4):551-555. http://www.cnki.com.cn/Article/CJFDTOTAL-DBDX201304023.htm
Pan X L, Yu H Y, Tu G F, et al.Effect of lime on digestion of gibbsitic bauxites at low temperature[J].Journal of Northeastern University (Natural Science), 2013, 34(4):551-555. http://www.cnki.com.cn/Article/CJFDTOTAL-DBDX201304023.htm
[9] 胡四春, 赵恒勤, 马化龙, 等. 海南某三水铝石型铝土矿常压溶出试验研究[J]. 2012, 32(增刊): 107-109.
http://d.wanfangdata.com.cn/periodical_kygc2012z1027.aspx Hu S C, Zhao H Q, Ma H L, et al.Research on Hainan a gibbsite bauxite pressure test at atmosphere[J].Mining and Metallurgical Engineering, 2012, 32(Supplement):107-109.
[10] 王刚, 薛忠秀.常压低温拜耳法新工艺研究[J].轻金属, 2013(3):11-15. http://www.cnki.com.cn/Article/CJFDTOTAL-QJSS201303004.htm
Wang G, Xue Z X.Research on new Bayer process at atmospheric pressure and low temperature[J].Light Metal, 2013(3):11-15. http://www.cnki.com.cn/Article/CJFDTOTAL-QJSS201303004.htm
-