Determination of Silica in Geological Samples by Silicon-Molybdenum Blue Spectrophotometry Using High-pressure Acid Digestion

Xue-lin DONG; Hai-yang HE; Qin CHU; Zhou SONG

doi:10.15898/j.cnki.11-2131/td.201708230132

2019 Vol. 38, No. 5

Article Contents

Article navigation > Rock and Mineral Analysis > 2019 > 38(5): 575-582

Next Article Previous Article

Xue-lin DONG, Hai-yang HE, Qin CHU, Zhou SONG. Determination of Silica in Geological Samples by Silicon-Molybdenum Blue Spectrophotometry Using High-pressure Acid Digestion[J]. Rock and Mineral Analysis, 2019, 38(5): 575-582. doi: 10.15898/j.cnki.11-2131/td.201708230132

Citation:

Xue-lin DONG, Hai-yang HE, Qin CHU, Zhou SONG. Determination of Silica in Geological Samples by Silicon-Molybdenum Blue Spectrophotometry Using High-pressure Acid Digestion[J]. Rock and Mineral Analysis, 2019, 38(5): 575-582. doi: 10.15898/j.cnki.11-2131/td.201708230132

Determination of Silica in Geological Samples by Silicon-Molybdenum Blue Spectrophotometry Using High-pressure Acid Digestion

1.
Hubei Province Geological Experimental Testing Center, Wuhan 430034, China
2.
Key Laboratory of Rare Mineral, Ministry of Land and Resources, Wuhan 430034, China
3.
School of Chemistry Engineering, Huazhong University of Science & Technology, Wuhan 430074, China

Received Date: 23 June 2018

Revised Date: 28 September 2018

Accepted Date: 16 July 2019

Abstract

Abstract

BACKGROUNDPolymerized silicic acid cannot be quantitatively complexed with molybdate in geological sample, therefore the silicon is determined by silicon-molybdenum blue colorimetric spectrophotometry. The key of this method is how to digest the solid sample to prepare a solution and ensure that the silicic acid occurs as a single molecule. OBJECTIVESTo completely digest the geological samples by high-pressure acid digestion without loss of silicon and polymerization of silicic acid. To improve the stability of silicon-molybdenum yellow by adding a stabilizing agent. METHODSHydrofluoric acid-nitric acid was used to digest the geological samples, so that the silicon in the sample was completely converted into fluorosilicic acid and was stably present in the solution. Boric acid and ammonium molybdate were added to make the excess hydrofluoric acid and boric acid to form stable BF₄^- dosing ion, which replaced the evaporation and removal of hydrofluoric acid, thus avoiding the volatilization loss of silicon and fluoride ions converted into gaseous SiF₄ during the acid removal process. Under the action of ammonium molybdate, silicon was fully converted into silicon molybdenum heteropolyacids. In the color development process, the stability of silicon-molybdenum yellow was significantly improved by adding acetone, and the absorbance was increased to some extent, thereby improving the color development effect of silicon by silicon-molybdenum blue pectrophotometry. RESULTSThe method avoided the problem that the silicic acid was easy to be polymerized during the acidification process when using the conventional alkali fusion digestion. A large amount of flux was introduced to cause a high blank. The validity of the method was evaluated by analyses of rock, soil, sediment and quartzite reference materials. The results of SiO₂ were in good agreement with certified values and the relative standard deviation (n=10) was less than 1%. CONCLUSIONSThis method is suitable for the rapid and accurate analysis of silica in common geological samples.
- rock /
- soil /
- sediment /
- silica /
- HF-HNO₃ dissolution /
- high-pressure digestion /
- spectrophotometry

FullText(HTML)

References

[1]	岩石矿物分析编委会.岩石矿物分析(第四版第一分册)[M].北京:地质出版社, 2011:8-17. Google Scholar The Editorial Committee of Rock and Mineral Analysis.Rock and Mineral Analysis (Fourth Edition:Volume Ⅰ)[M]. Beijing:Geological Publishing House, 2011:8-17. Google Scholar
[2]	刘建国, 王粤新.重量法测定岩石矿物中二氧化硅的几种凝聚剂[J].岩矿测试, 1994, 13(2):134-136. Google Scholar Liu J G, Wang Y X.Coagulating agents for gravimetric determination of silica in rocks and minerals[J]. Rock and Mineral Analysis, 1994, 13(2):134-136. Google Scholar
[3]	张志刚, 杨淑珍, 黄友芬.硅酸盐环境标准参考物质中硅的定值方法——氟硅酸钾容量法[J].环境科学, 1990, 11(5):48-52. doi: 10.3321/j.issn:0250-3301.1990.05.008 CrossRef Google Scholar Zhang Z G, Yang S Z, Huang Y F.Volumetric method for silicon determination in certified reference silicates-potassium silicofluoride volumetry[J]. Chinese Journal of Environmental Science, 1990, 11(5):48-52. doi: 10.3321/j.issn:0250-3301.1990.05.008 CrossRef Google Scholar
[4]	严海, 段家华, 马林泽.碱熔-氟硅酸钾容量法测定钒钛高炉渣中二氧化硅的含量[J].昆明冶金高等专科学校学报, 2014, 30(1):10-14. doi: 10.3969/j.issn.1009-0479.2014.01.003 CrossRef Google Scholar Yan H, Duan J H, Ma L Z.Alkali fusion-potassium fluorosilicate volumetric determination of silica content in slag with vanadium and titanium[J]. Journal of Kunming Metallurgy College, 2014, 30(1):10-14. doi: 10.3969/j.issn.1009-0479.2014.01.003 CrossRef Google Scholar
[5]	王艳红, 张瑞峰.酸溶-氟硅酸钾容量法测定锌铝硅合金中硅[J].有色矿冶, 2018, 34(1):65-67. Google Scholar Wang Y H, Zhang R F.Determination of silicon in zinc-aluminum-silicon alloy by acid solution-fluosilicate capacity[J]. Non-Ferrous Mining and Metallurgy, 2018, 34(1):65-67. Google Scholar
[6]	Archer F A, Jr K W S.Spectrophotometric determination of silicon in bismuth borosilicate glass by flow injection[J]. Analytica Chimica Acta, 1992, 262(2):243-251. doi: 10.1016/0003-2670(92)80061-B CrossRef Google Scholar
[7]	高立红, 周凯红, 王燕霞, 等.硅钼蓝分光光度法测定氟化稀土中二氧化硅[J].冶金分析, 2017, 37(4):57-61. Google Scholar Gao L H, Zhou K H, Wang Y X, et al.Determination of silicon dioxide in rare earth fluoride by silicomolybdic blue spectrophotometry[J]. Metallurgical Analysis, 2017, 37(4):57-61. Google Scholar
[8]	白小叶, 褚晓君.硅钼蓝分光光度法测定铬铁矿石中的二氧化硅[J].有色矿冶, 2016, 32(4):51-53. doi: 10.3969/j.issn.1007-967X.2016.04.017 CrossRef Google Scholar Bai X Y, Chu X J.Determination of silicon in chromite by using silicomolybdenum blue spectrophotometry[J]. Non-Ferrous Mining and Metallurgy, 2016, 32(4):51-53. doi: 10.3969/j.issn.1007-967X.2016.04.017 CrossRef Google Scholar
[9]	洪达峰.硅钼蓝分光光度法测定高岭土中二氧化硅[J].冶金分析, 2017, 37(10):59-64. Google Scholar Hong D F.Determination of silicon dioxide in kaolin by silicon molybdenum blue spectrophotometry[J]. Metallurgical Analysis, 2017, 37(10):59-64. Google Scholar
[10]	王琰, 孙洛新, 张帆, 等.电感耦合等离子体发射光谱法测定含刚玉的铝土矿中硅铝铁钛[J].岩矿测试, 2013, 32(5):719-723. doi: 10.3969/j.issn.0254-5357.2013.05.008 CrossRef Google Scholar Wang Y, Sun L X, Zhang F, et al.Determination of Si, Al, Fe and Ti in bauxite by inductively coupled plasma-atomic emission spectrometry[J]. Rock and Mineral Analysis, 2013, 32(5):719-723. doi: 10.3969/j.issn.0254-5357.2013.05.008 CrossRef Google Scholar
[11]	赵良成, 郭秀平, 胡艳巧, 等.碳酸钠碱熔-电感耦合等离子体发射光谱法测定石墨中的常量元素硅铝钙镁铁钛锰磷[J].岩矿测试, 2015, 34(3):308-313. Google Scholar Zhao L C, Guo X P, Hu Y Q, et al.Simultaneous determination of major elements Si, Al, Ca, Mg, Fe, Ti, Mn and P in graphite by inductively coupled plasma-optical emission spectrometry with sodium carbonate fusion[J]. Rock and Mineral Analysis, 2015, 34(3):308-313. Google Scholar
[12]	黄超冠, 蒙义舒, 郭焕花, 等.过氧化钠碱熔-电感耦合等离子体发射光谱法测定钛铝合金中的铬铁钼硅[J].岩矿测试, 2018, 37(1):30-35. Google Scholar Huang C G, Meng Y S, Guo H H, et al.Determination of chromium, iron, molybdenum and silicon in Ti-Al alloy by inductively coupled plasma-optical emission spectrometry with sodium peroxide alkali fusion[J]. Rock and Mineral Analysis, 2018, 37(1):30-35. Google Scholar
[13]	王梅英, 李鹏程, 李艳华, 等.蓝晶石矿中氟钠镁铝硅铁钛钾钙元素的X射线荧光光谱分析[J].岩矿测试, 2013, 32(6):909-914. doi: 10.3969/j.issn.0254-5357.2013.06.011 CrossRef Google Scholar Wang M Y, Li P C, Li Y H, et al.Analysis of F, Na, Mg, Al, Si, Fe, Ti, K, and Ca in cyanite ores by X-ray fluorescence spectrometry[J]. Rock and Mineral Analysis, 2013, 32(6):909-914. doi: 10.3969/j.issn.0254-5357.2013.06.011 CrossRef Google Scholar
[14]	褚宁, 李卫刚, 蒋晓光, 等.熔融制样波长色散X射线荧光光谱法测定白云石中钙镁硅铁铝[J].岩矿测试, 2014, 33(6):834-838. Google Scholar Chu N, Li W G, Jiang X G, et al.Determination of calcium, magnesium, silicon, iron and aluminum in dolomite by wavelength dispersive X-ray fluorescence spectrometry with fusion sample preparation[J]. Rock and Mineral Analysis, 2014, 33(6):834-838. Google Scholar
[15]	赵伟, 夏传波, 姜云, 等.X射线荧光光谱法测定透辉石中氧化钙、氧化镁和二氧化硅[J].冶金分析, 2018, 38(3):29-34. Google Scholar Zhao W, Xia C B, Jiang Y, et al.Determination of calcium oxide, magnesium oxide and silicon dioxide in diopside by X-ray fluorescence spectrometry[J]. Metallurgical Analysis, 2018, 38(3):29-34. Google Scholar
[16]	李可及.熔融制样X射线荧光光谱法测定岩盐中的主量成分[J].岩矿测试, 2016, 35(3):290-294. Google Scholar Li K J.Determination of major components in rock salt by X-ray fluorescence spectrometry with sample fusion[J]. Rock and Mineral Analysis, 2016, 35(3):290-294. Google Scholar
[17]	凌进中.硅酸盐岩石的分解方法[J].岩矿测试, 1988, 7(4):317-323. Google Scholar Ling J Z.Decomposition of silicates[J]. Rock and Mineral Analysis, 1988, 7(4):317-323. Google Scholar
[18]	Yu Z, Robinson P, Mcgoldrick P.An evaluation of me-thods for the chemical decomposition of geological materials for trace element determination using ICP-MS[J]. Geostandards and Geoanalytical Research, 2001, 25(2-3):199-217. doi: 10.1111/j.1751-908X.2001.tb00596.x CrossRef Google Scholar
[19]	李献华, 刘颖, 涂湘林, 等.硅酸盐岩石化学组成的ICP-AES和ICP-MS准确测定:酸溶与碱熔分解样品方法的对比[J].地球化学, 2002, 31(3):289-294. doi: 10.3321/j.issn:0379-1726.2002.03.010 CrossRef Google Scholar Li X H, Liu Y, Tu X L, et al.Precise determination of chemical compositions in silicate rocks using ICP-AES and ICP-MS:A comparative study of sample digestion techniques of alkali fusion and acid dissolution[J]. Geochimica, 2002, 31(3):289-294. doi: 10.3321/j.issn:0379-1726.2002.03.010 CrossRef Google Scholar
[20]	Cotta A J B, Enzweiler J.Classical and new procedures of whole rock dissolution for trace element determination by ICP-MS[J]. Geostandards and Geoanalytical Research, 2012, 36(1):27-50. doi: 10.1111/j.1751-908X.2011.00115.x CrossRef Google Scholar
[21]	García de Madinabeitia S, Sánchez Lorda M E, Ibarguchi J I G.Simultaneous determination of major to ultratrace elements in geological samples by fusion-dissolution and inductively coupled plasma mass spectrometry techniques[J]. Analytica Chimica Acta, 2008, 625(2):117-130. doi: 10.1016/j.aca.2008.07.024 CrossRef Google Scholar
[22]	Okina O, Lyapunov S, Avdosyeva M, et al.An investi-gation of the reliability of HF acid mixtures in the bomb digestion of silicate rocks for the determination of trace elements by ICP-MS[J]. Geostandards and Geoanalytical Research, 2016, 40(4):583-597. doi: 10.1111/ggr.12124 CrossRef Google Scholar
[23]	黎卫亮, 程秀花, 余娟, 等.高压密闭酸溶-电感耦合等离子体质谱法测定花岗闪长岩中的微量锆[J].岩矿测试, 2016, 35(1):32-36. Google Scholar Li W L, Cheng X H, Yu J, et al.Determination of trace zirconium in granodiorite by inductively coupled plasma-mass spectrometry with sealed acid digestion at high pressure[J]. Rock and Mineral Analysis, 2016, 35(1):32-36. Google Scholar
[24]	赵中一, 何应律.岩石矿物分析导论[M].武汉:中国地质大学出版社, 1993. Google Scholar Zhao Z Y, He Y L.Introduction to Rock and Mineral Analysis[M]. Wuhan:China University of Geosciences Press, 1993. Google Scholar
[25]	杨朝帅, 周建辉, 孔幸花, 等.硅钼蓝光度法测定萤石及其精矿中二氧化硅的含量[J].冶金分析, 2012, 32(7):59-62. doi: 10.3969/j.issn.1000-7571.2012.07.013 CrossRef Google Scholar Yang C S, Zhou J H, Kong X H, et al.Silicon-molybdenum blue spectrophotometric determination of silica in fluorite and its concentrate[J]. Metallurgical Analysis, 2012, 32(7):59-62. doi: 10.3969/j.issn.1000-7571.2012.07.013 CrossRef Google Scholar
[26]	沙德仁.提高硅钼黄比色溶液稳定性的研究[J].玻璃纤维, 2010(4):18-28. doi: 10.3969/j.issn.1005-6262.2010.04.005 CrossRef Google Scholar Sha D R.Study of improving the stability of colorimetric solution of silicon molybdenum yellow[J]. Fiber Glass, 2010(4):18-28. doi: 10.3969/j.issn.1005-6262.2010.04.005 CrossRef Google Scholar
[27]	Uchida H, Uchida T, Iida C.Determination of major and minor elements in silicates by inductively coupled plasma emission spectrometry[J]. Analytica Chimica Acta, 1979, 108:87-92. doi: 10.1016/S0003-2670(01)93043-0 CrossRef Google Scholar
[28]	俞超, 蒋增辉, 汪永喜, 等.氢氟酸溶解-电感耦合等离子体原子发射光谱法测定海绵钛中硅、铁、锰及镁[J].分析化学, 2013, 41(11):1782-1783. Google Scholar Yu C, Jiang Z H, Wang Y X, et al.Determination of Si, Fe, Mn, Mg in sponge titanium dissolved in HF acid by inductively coupled plasma atomic emission spectrometry[J]. Chinese Journal of Analytical Chemistry, 2013, 41(11):1782-1783. Google Scholar
[29]	胡德新, 肖葵, 王向东, 等.微波消解-电感耦合等离子体发射光谱法测定高碳铬铁中硅锰磷[J].岩矿测试, 2014, 33(2):208-211. doi: 10.3969/j.issn.0254-5357.2014.02.009 CrossRef Google Scholar Hu D X, Xiao K, Wang X D, et al.Determination of silicon manganese and phosphorus in high carbon-chrome iron by inductively coupled plasma-atomic emission spectrometry after microwave digestion[J]. Rock and Mineral Analysis, 2014, 33(2):208-211. doi: 10.3969/j.issn.0254-5357.2014.02.009 CrossRef Google Scholar
[30]	张建珍, 王锦荣, 刘家齐.聚合硅酸解聚-硅钼蓝分光光度法测定矿石中二氧化硅[J].冶金分析, 2010, 30(9):65-69. doi: 10.3969/j.issn.1000-7571.2010.09.014 CrossRef Google Scholar Zhang J Z, Wang J R, Liu J Q.Determination of silicon dioxide in ore by polymerized silicic acid depolymerization-molybdosilicate blue spectrophoto-metry[J]. Metallurgical Analysis, 2010, 30(9):65-69. doi: 10.3969/j.issn.1000-7571.2010.09.014 CrossRef Google Scholar
[31]	赵玲, 李胜生, 冯永明, 等.氟化物解聚快速测定铁矿石中二氧化硅[J].安徽地质, 2012, 22(4):305-307. doi: 10.3969/j.issn.1005-6157.2012.04.018 CrossRef Google Scholar Zhao L, Li S S, Feng Y M, et al.Quick determination of SiO₂ in iron ore by fluoride depolymerization[J]. Geology of Anhui, 2012, 22(4):305-307. doi: 10.3969/j.issn.1005-6157.2012.04.018 CrossRef Google Scholar