氢氧化钠溶出-电感耦合等离子体原子发射光谱法测定三门峡地区一水硬铝石型铝土矿中氧化铝实际溶出率  

Determination of alumina actual dissolution rate in diaspore type bauxite from Sanmenxia area by inductively coupled plasma atomic emission spectrometry with sodium hydroxide dissolution

作　　者：任金鑫 闫东飞 班俊生 REN Jinxin;YAN Dongfei;BAN Junsheng(Henan Second Geological Brigade Co.,Ltd.,Zhengzhou 450016,China)

机构地区：[1]河南省第二地质大队有限公司,河南郑州450016

出　　处：《冶金分析》2024年第6期69-73,共5页Metallurgical Analysis

基　　金：河南省豫地科技集团有限公司2023年度科技项目(JTZCKY2023019)。

摘　　要：溶出率是衡量一水硬铝石型铝土矿质量的重要指标,通常在计算Al_(2)O_(3)实际溶出率时,因用来溶出铝土矿中Al_(2)O_(3)的母液中含有大量的Al_(2)O_(3),故需要先对溶出Al_(2)O_(3)后的试液进行过滤、洗涤、烘干得到赤泥,再对赤泥消解后测定其中Al_(2)O_(3)的含量,然后经过换算才能得到最终的结果,操作较为繁琐。实验采用高压消解技术,模拟高温拜耳法氧化铝生产工艺,使用与生产工艺浓度一致的NaOH溶液代替生产工艺中的母液将铝土矿中Al_(2)O_(3)溶出,用电感耦合等离子体原子发射光谱法(ICP-AES)对溶出液中Al_(2)O_(3)进行测定,可直接测得溶出Al_(2)O_(3)的含量,然后用溶出Al_(2)O_(3)含量除以Al_(2)O_(3)总量计算得到Al_(2)O_(3)的实际溶出率,建立了测定三门峡地区一水硬铝石型铝土矿中Al_(2)O_(3)实际溶出率的方法。在选定条件下,Al_(2)O_(3)的质量浓度在10~100μg/mL范围内与其对应的发射光强度呈线性关系,校准曲线线性方程的相关系数为0.9999;方法检出限为0.04%。按照实验方法测定一水硬铝石型铝土矿样品中溶出Al_(2)O_(3)和Al_(2)O_(3)实际溶出率,溶出Al_(2)O_(3)测得结果的相对标准偏差(RSD,n=6)为0.67%~0.92%,Al_(2)O_(3)实际溶出率为68.51%~84.14%。分别按照实验方法和其他方法(先测定赤泥中Al_(2)O_(3)含量,再通过差减法计算得到溶出Al_(2)O_(3)含量)测定一水硬铝石型铝土矿中溶出Al_(2)O_(3)含量,并计算Al_(2)O_(3)实际溶出率。结果表明,两种方法测得结果相一致。Dissolution rate is an important index for measuring the quality of diaspore type bauxite.Usually,when calculating Al_(2)O_(3) actual dissolution rate,since the mother solution used to dissolve Al_(2)O_(3) in bauxite contains a large amount of Al_(2)O_(3),it is necessary to first filter,wash and dry the test solution after dissolving Al_(2)O_(3) to obtain red mud,and then determine the content of Al_(2)O_(3) in red mud after digestion to obtain the final result after conversion.The operation is more complicated.The high-pressure digestion technology was used to simulate high-temperature Bayer alumina production process.NaOH solution with the same concentration as the production process was used to replace the mother solution in the production process to dissolve Al_(2)O_(3) in the bauxite.The content of Al_(2)O_(3) in solution was determined by inductively coupled plasma atomic emission spectrometry(ICP-AES).Therefore,the content of soluble Al_(2)O_(3) could be directly determined.Then,Al_(2)O_(3) actual dissolution rate could be calculated through dividing soluble Al_(2)O_(3) content by the total content of Al_(2)O_(3).Consequently,a method for determination of Al_(2)O_(3) actual dissolution rate in diaspore type bauxite from Sanmenxia area was established.Under the selected conditions,the mass concentration of Al_(2)O_(3) in range of 10-100μg/mL had a linear relationship with its corresponding emission intensity.The correlation coefficient of calibration curve linear equation was 0.9999.The detection limit of this method was 0.04%.The soluble Al_(2)O_(3) content and Al_(2)O_(3) actual dissolution rate in diaspore type bauxite samples were determined according to the proposed method.The relative standard deviation(RSD,n=6)of determination results for soluble Al_(2)O_(3) were between 0.67% and 0.92%.The Al_(2)O_(3) actual dissolution rates were in range of 68.51%-84.14%.The contents of soluble Al_(2)O_(3) in diaspore type bauxite samples were determined according to the proposed method and other method(the conte

关 键 词：三门峡地区 一水硬铝石型 铝土矿 实际溶出率 氧化铝 氢氧化钠 电感耦合等离子体原子发射光谱法(ICP-AES) 

分 类 号：O657.31[理学—分析化学] P574.2[理学—化学]