Research Article | Open Access
Zhang-kuang Peng, Zhi-na Liu, "Accurate Determination of Boron Content in Halite by ICP-OES and ICP-MS", International Journal of Analytical Chemistry, vol. 2019, Article ID 9795171, 5 pages, 2019. https://doi.org/10.1155/2019/9795171
Accurate Determination of Boron Content in Halite by ICP-OES and ICP-MS
Boron element is widely distributed in different geologic bodies, and there are important geo-chemical applications in earth science. Halite is a common mineral found in sediment basin. However there is no good method to accurately measure the boron content in halite, which is mainly because Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) and Inductively Coupled Plasma Mass Spectrometer (ICP-MS) are limited by the high salt matrix interference and the instrument detection limit. Thus enriching the boron element and removing the matrix interference are necessary before the measuring. In this paper, Amberlite IRA 743 boron-specific resin was applied to enrich the boron element and remove most of the high-salt matrix. The strong acid cation resin (Dowex 50 W×8, 200-400 mesh, USA) and weak-base anion resin (Ion Exchanger II, Germany) were mixed with equal volume, which could remove the foreign ions completely: meanwhile, the relative content of boron in the solution reached above 98%, and the recoveries ranged from 97.8% to 104%. 208.900 nm was chosen as the detection wavelength for ICP-OES, and the detection identification and quantification limits were 0.006 mg·L−1 and 0.02 mg·L−1, respectively. 11B was chosen as the measuring element for ICP-MS, and the detection identification and quantification limits were severally 0.036 mg·L−1 and 0.12 mg·L−1. The relative standard deviations ranged from 1.4% to 3.4% through six replicates under different salinities. Therefore, the process could be regarded as a feasible method to measure boron content in halite by ICP-OES and ICP-MS.
The boron is a strongly incompatible element in the earth , which makes the boron remain in the solution during the evaporation, and, with the development of evaporation, the boron content in the halite increases [2, 3]. As the boron gets into the halite in the form of inclusion, it could reflect the salinity of the paleo-lake water as well as drier paleoclimatic conditions. The geo-chemical behavior of boron in halite is a useful tool to study the evolution and chemical composition of salt lake [2–5]. However, there were few reports about measuring the boron content in halite. Spectrophotometry is a common method for the determination of boron content in many minerals, such as biological sample, soil, plants, and food [6–11]; meanwhile it was the only method to measure the boron content in boron-rich halite formed in laboratory . Due to the low sensitivity and serious matrix interference, it is not good for measuring the boron content in natural halite.
Because of the high sensitivity and rapid analysis, the ICP-MS and ICP-OES are good methods for measuring the boron content in different minerals, such as coal, quartz, and other geochemical samples [12–15]. However, there was no report about using ICP-MS and ICP-OES to measure the boron content in halite. Though dilution is the commonest method to overcome the high-salt matrix interference, it is not for measuring the boron content in halite because it will cause the boron content in the solution to fall below the detection limit of the instrument. So preenrichment of boron element and reducing the salinity from solution are the keys to successfully measure the boron content in halite by ICP-OES or ICP-MS. In this paper, Amberlite IRA 743 boron-specific resin was used to enrich boron and remove most of the NaCl. Then elute the adsorbed boron from the resin with hydrochloric acid, whose volume, content, and temperature were 10 mL, 0.1 mol·L−1, and 75°C, respectively. The conditions of eluent were reported by Xiao et al., who found that the boron was hard to be eluted from the boron-special resin even if the concentration of HCl reached 2 mol·L−1, while it can be easily eluted by HCl in high temperature . The strong acid cation resin (Dowex 50 W×8, 200-400 mesh, USA) and weak-base anion resin (Ion Exchanger II, Germany) were mixed with equal volume to remove NaCl and HCl. Finally send the solution to measure boron content by ICP-OES and ICP-MS.
2. Material and Methods
Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES, ICAP 6500 DUO, Thermo Electron): RF power was 1150 W; flux of cooling air was 15 L·min−1; flux of auxiliary air was 0.5 L·min−1; flux of carrying-air was 0.55 L·min−1; pump speed was 60 r·min−1; observation way of plasma was automatic.
Inductively Coupled Plasma Mass Spectrum (ICP-MS, X series 2 type, Thermo Electron): RF power was 1250 W; flux of cooling air (Ar) was 12.0 L·min−1; flux of auxiliary was 0.75 L·min−1; atomizer flow (Ar) was 0.85 L·min−1; measuring method was peak jumping with 11B.
Boric acid solid (H3BO3, GR) and sodium chloride solid (NaCl, GR) were made in Beijing Reagent Factory. Balanced hydrochloric acid was made from concentrated hydrochloric acid (GR): sub-boiling ammonia. Deionized water was made through multiple distillation and then the boron was removed by Amberlite IRA 743 type boron-specific resin made in American Rohm & Hass Company. It contains hydrophobic styrene skeleton and tertiary amine group and can strongly adsorb borate anion from alkaline solution with an exchange capacity of 10.9 mg B•g−1 . Mixed resin was made of an equal volume of strong acid cation resin (Dowex 50 W×8, 200-400 mesh, USA) and weak-base anion resin (Ion Exchanger II, Germany).
Natural Samples: natural salt samples came from ZK309 Drill Hole, Long-hu Diggings, Laos (ZK-03, ZK-04, ZK-10), and salt lake in Pakistan (KR03-2, BS01-2, KS05).
2.3. Certified Reference Materials, Samples, and Sample Preparation
Prepare a standard solution of 10 mg·L−1 boron, and then use it and NaCl to make a series of mixtures with boron content from 10 μg to 70 μg and NaCl from 500 mg·L−1 to 50000 mg·L−1. Because the boron was only adsorbed by boron-special resin in the form of in the alkaline solution, the sub-boiling ammonia is used to adjust the pH of the solution to 7~8 , and then the purification process of boron-specific resin is carried out by previous studies . Boron is eluted from the resin with 10 mL 0.1 mol·L−1 HCl at 75°C, and then mix the strong acid cation resin (Dowex 50 W×8, 200-400 mesh, USA) and weak-base anion resin (Ion Exchanger II, Germany) with equal volume to remove the foreign ions from the eluent. Finally determine boron content by ICP-OES and ICP-MS. During step one, the boron is adsorbed by boron-special resin in the form of . Next the foreign ions are adsorbed by the mixed resins in which the boron exists in the form of H3BO3 in solution, and it is separated from foreign ions.
For numbers ZK-03, ZK-04, ZK-10, KR03-2, BS01-2, and KS05, weight 5.0 g halite and dissolve them into 50 mL deionized water. Remove the high-salt matrix and enrich the boron element using the above method.
3. Result and Discussion
3.1. The Result of Boron Recovery
The recovery of boron in the pure solutions ranged from 97.6% to 102.34% (Table 1), which indicated that the boron is not lost during the adsorption and eluting, and all the boron could be recovered completely by the resins. Comparing the values measured by ICP-OES with those by ICP-MS, they were found to be consistent (Figure 1) and the same as the contents of boron in original solutions.
The recoveries of boron in solutions under different salinities ranged from 99.95% to 103.3% (Table 2), which were consistent with the results of pure solution and showed that the salinity had no effect on the adsorption of boron-specific resin and mixed resins. The results demonstrated that the high salt matrix interference of the solution could be excluded effectively, which is suitable for the detection of the boron content by ICP-OES and ICP-MS after removing the high-salt matrix and enriching the boron element. And this method provided a good way to measure the boron content in halite.
The recovery of additional standard of the natural halite (ZK-04, ZK-10) ranged from 98.8% to 106.00% (Table 3), which showed that all the boron of the natural halite was recovered completely by resins. The dissolution of the halite in water, as well as the enrichment and removal of the matrix in the resins, did not result in the loss of boron. There was no difference between the boron contents of the halite measured by ICP-OES and ICP-MS.
3.2. Separating Effect by Resins
In order to discuss the separating effect between boron element and foreign ions, three natural samples and four synthetic brines were processed based on the above method. The amounts of foreign ions were measured, whose results (Table 4) showed that the foreign ions in the original solution were removed completely and the relative content of boron reached above 97%. Thus this method was great for the detection of boron content by ICP-OES and ICP-MS.
The data in the parentheses represented the results of measuring by ICP-MS, and the other data represented the results of measuring by ICP-OES.
3.3. The Detection Identifications of Boron Content by ICP-OES and ICP-MS
Take the deionized water through the entire process as a blank solution. Perform 11 consecutive measurements, and define 3 times standard deviation of the measurement results as the detection identification, 2 times the detection identification as the identification limit, and 10 times the standard deviation as the quantification limit for boron element . All the parameters were showed in Table 5. If the salinity of the solution was reduced just by dilution, it would cause the boron content of the solution to be lower than the detection limit and quantification limit of ICP-OES and ICP-MS.
3.4. The Method Repeatability Test
Repeatedly test solutions at different salinities 6 times, whose results which were showed in Table 6 indicated that the standard deviation ranged from 1.4% to 3.4%, and all the values were less than 5%. So we think that the method is feasible and there is no accidental error for the boron content determination of halite by ICP-OES and ICP-MS.
3.5. The Boron Contents of Natural Samples
The boron contents of natural samples which were showed in Figure 2 ranged from 0.3684 mg·L−1 to 1.029 mg·L−1, the measuring values of which were beyond the identification limits and the quantification limits of ICP-OES and ICP-MS. The values of natural halite measured by ICP-OES were consistent with those by ICP-MS. Conversely, if only dilution was performed, the boron content in the solution would be similar to the detection limit and the quantitation limit of the instrument; therefore the dilution method could not be applied for the detection of boron content of the halite by ICP-OES and ICP-MS. Comparing the boron content of the halite of Long-hu Diggings, Laos (ZK-03, ZK-04, ZK-10), with that of the salt lake in Pakistan (KR03-2, BS01-2, KS05), we found that the boron contents in Laos halite were higher than those in Pakistan halite. This result was consistent with the geological phenomenon that there are borate mineral inclusions in Long-hu Diggings, Laos [20, 21].
The boron-specific resin could significantly enrich the boron in high-salt solution and remove the matrix, which is suitable for the detection of the boron content of halite by ICP-OES and ICP-MS, whose standard addition recovery ranged from 97.5% to 106.0, and the relative standard deviations of the repeated experiments were less than 5%.
The data used to support the findings of this study are included within the article.
Conflicts of Interest
The authors declare that they have no conflicts of interest.
- W. P. Leeman and V. B. Sisson, “Geochemistry of boron and its implications for crustal and mantle processes,” in Boron: Mineralogy, Petrology and Geochemistry, Reviews in Mineralogy, E. S. Grew and L. M. Anovitz, Eds., vol. 33, pp. 645–695, Mineralogical Society of America, Washington, D.C., USA, 1996.
- Y. S. Du, Q. S. Fan, D. L. Gao et al., “Evalution of boron isotopes in halite as an indicator of the salinity of Qarhan paleolake water in the eastern Qaidam Basin, western China,” Geoscience Frontiers, no. 1, pp. 1–10, 2019.
- Q. S. Fan, Y. Q. Ma, H. D. Chen et al., “Boron occurrence in halite and boron isotope geochemistry of halite in the Qarhan Salt Lake, western China,” Sedimentary Geology, vol. 322, pp. 34–42, 2015.
- W. G. Liu, Y. K. Xiao, Z. C. Peng, Z. S. An, and X. X. He, “Boron concentration and isotopic composition of halite from experiments and salt lakes in the Qaidam Basin,” Geochimica Et Cosmochimica Acta, vol. 64, no. 13, pp. 2177–2183, 2000.
- G. Paris, J. Gaillardet, and P. Louvat, “Geological evolution of seawater boron isotopic composition recorded in evaporites,” Geology, vol. 38, no. 11, pp. 1035–1038, 2010.
- M. A. Wimmer and H. E. Goldbach, “A miniaturized curcumin method for the determination of boron insolutions and biological samples,” Journal of Plant Nutrition and Soil Science, vol. 162, pp. 15–18, 1999.
- Y. K. Xiao, B. Y. Liao, W. G. Liu et al., “Ion exchange extraction of boron from aqueous fluids by Amberlite IRA 743 resin,” Chinese Journal of Chemistry, vol. 21, no. 8, pp. 1073–1079, 2003.
- S. Thangavel, S. M. Dhavile, K. Dash, and S. C. Chaurasia, “Spectrophotometric determination of boron in complex matrices by isothermal distillation of borate ester into curcumin,” Analytica Chimica Acta, vol. 502, no. 2, pp. 265–270, 2004.
- D. M. Gomes, M. A. Segundo, J. L. Lima, and A. O. Rangel, “Spectrophotometric determination of iron and boron in soil extracts using a multi-syringe flow injection system,” Talanta, vol. 66, no. 3, pp. 703–711, 2005.
- R. Shekhar, J. Arunachalam, G. R. Krishna, H. R. Ravindra, and B. Gopalan, “Determination of boron in Zr–Nb alloys by glow discharge quadrupole mass spectrometry,” Journal of Nuclear Materials, vol. 340, no. 2-3, pp. 284–290, 2005.
- L. Zaijun, C. Zhengwei, and T. Jian, “The determination of boron in food and seed by spectrophotometry using a new reagent 3,4-dihydroxyazomethine-H,” Food Chemistry, vol. 94, no. 2, pp. 310–314, 2006.
- F. G. Smith, D. R. Wiederin, R. S. Houk, C. B. Egan, and R. E. Serfass, “Measurement of boron concentration and isotope ratios in biological samples by inductivey coupled plasma mass spectrometry with direct injection nebulization,” Analytica Chimica Acta, vol. 248, no. 1, pp. 229–234, 1991.
- A. M. S. Nyomora, R. N. Sah, P. H. Brown, and R. O. Miller, “Boron determination in biological materials by inductively coupled plasma atomic emission and mass spectrometry: effects of sample dissolution methods,” Fresenius' Journal of Analytical Chemistry, vol. 357, no. 8, pp. 1185–1191, 1997.
- C. H. Yang and S. J. Jiang, “Determination of B, Si, P and S in steels by inductively coupled plasma quadrupole mass spectrometry with dynamic reaction cell,” Spectrochimica Acta Part B: Atomic Spectroscopy, vol. 59, no. 9, pp. 1389–1394, 2004.
- A. G. Coedo, M. T. Dorado, and I. Padilla, “Evaluation of different sample introduction approaches for the determination of boron in unalloyed steels by inductively coupled plasma mass spectrometry,” Spectrochimica Acta Part B: Atomic Spectroscopy, vol. 60, no. 1, pp. 73–79, 2005.
- Y. K. Xiao, Y. Xiao, G. H. Swihart, and W. G. Liu, “The investigation of ion exchange technique for extracting boron from aqueous fluids by boron specific ion exchange resin,” Acta Geoscientia Sinica, vol. 18, pp. 286–289, 1997.
- J. K. Aggarwal, M. B. Shabani, M. R. Palmer, and K. V. Ragnarsdottir, “Determination of the rare earth elements in aqueous samples at sub-ppt levels by inductively coupled plasma mass spectrometry and flow injection ICPMS,” Analytical Chemistry, vol. 68, pp. 4418–4423, 1996.
- W. P. Leeman, R. D. Vocke Jr., E. S. Beary, and P. J. Paulsen, “Precise boron isotopic analysis of aqueous samples: Ion exchange extraction and mass spectrometry,” Geochimica et Cosmochimica Acta, vol. 55, no. 12, pp. 3901–3907, 1991.
- V. Sandroni, C. M. M. Smith, and A. Donovan, “Microwave digestion of sediment, soils and urban particulate matter for trace metal analysis,” Talanta, vol. 60, no. 4, pp. 715–723, 2003.
- H. B. Tan, H. Z. Ma, B. K. Li, X. Y. Zhang, and Y. K. Xiao, “Strontium and boron isotopic constraint on the marine origin of the khammuane potash deposits in southeastern laos,” Chinese Science Bulletin, vol. 55, pp. 3181–3188, 2010.
- X. Y. Zhang, H. Z. Ma, Y. Q. Ma, Q. L. Tang, and X. L. Yuan, “Origin of the late Cretaceous potash-bearing evaporites in the Vientiane Basin of Laos: δ11B evidence from borates,” Journal of Asian Earth Sciences, vol. 62, pp. 812–818, 2013.
Copyright © 2019 Zhang-kuang Peng and Zhi-na Liu. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.