Organic acids and inorganic anions in Bayer liquors by ion chromatography after solid-phase extraction

Abstract

A method for the simultaneous separation and determination of organic acids and inorganic anions in Bayer liquors was developed by gradient ion chromatography with suppressed conductivity detection. Formate, acetate, propionate, oxalate, succinate, glutarate, fluoride, chloride and sulfate were separated and determined in 33 min. The samples were pretreated with solid-phase extraction, which has high selectivity for removing a large number of metallic ions in the Bayer liquors, and filtered with a 0.45 μm filter membrane before being injected into the ion chromatographic system. The separation of six organic acids and three inorganic anions was achieved on an IonPac AS11-HC column with KOH as the eluent, and the detection was performed by a conductivity detection mode. No interference is found in the presence of fluorate, chlorate and sulphate when organic acids are determined. The calibration graphs of peak area for all the analytes are linear over a wide range. The relative standard derivation of the peak area of analytes is less than 2.14%. Under optimum conditions the detection ranges from 0.2 to 100.0 mg/L. The average recoveries of the added standards are between 94.3% and 102.8%.

Keywords

Bayer liquors / organic acid / inorganic anion / ion chromatography / solid-phase extraction

References

[1] GrocottS. C., JefferiesL. P., BowserT., et al. . Applications of ion chromatography and capillary ion electrophoresis in the alumina and aluminium industry[J]. J Chromatogr A, 1992, 602(1/2): 257-264

[2] ZhangB., ChenQ. Y., ZhouK. C.. Effect of modified additives on process of seeded precipitation ratio of sodium aluminate liquors[J]. J Cent South Univ: Science and Technology, 2006, 37(5): 932-936

[3] ChenG. H., ChenQ. Y., YinZ. L., et al. . Spectral dimension during the precipitation of gibbsite from the seeded caustic aluminate solutions[J]. J Cent Douth Univ: Science and Technology, 2002, 33(2): 157-159

[4] CardwellT. J., LaughtonW. R.. Analysis of fluoride, acetate and formate in Bayer liquors by ion chromatography[J]. J Chromatogr A, 1994, 678(2): 364-369

[5] RomanoJ., JandikP., JonesW. R., et al. . Optimization of inorganic capillary electrophoresis for the analysis of anionic solutes in real samples[J]. J Chromatogr A, 1991, 546(1/2): 411-421

[6] LaksanaS., HaddadP. R.. Dialytic clean-up of alkaline samples prior to ion chromatographic analysis[J]. J Chromatogr A, 1992, 602(1/2): 57-63

[7] HaddadP. R., JacksonP. E.Ion Chromatography—Principles and Applications[M], 1990, Amsterdam, Elsevier

[8] CalaloR., TranT.. Effects of sodium oxalate on the precipitation of alumina trihydrate from synthetic sodium aluminate liquors[J]. Light Metals, 1993, 49(2): 125-133

[9] BrownN., ColeT. J.. The behaviour of sodium oxalate in a bayer alumina plant[J]. Light Metals, 1980, 15(1/2): 105-117

[10] VogelA. R.Textbook of Quantitative Inorganic Analysis[M], 19864th ed.Harlow, Longman: 352

[11] BOWSER T, GROCOTT S C. Ion chromatography in the alumina and aluminum industries[C]// Proceedings of the 2nd International Alumina Quality Workshop. Perth, 1990.

[12] JacksonP. E.. Analysis of oxalate in Bayer liquors: a comparison of ion chromatography and capillary electrophoresis[J]. J Chromatogr A, 1995, 693(1): 155-161

[13] ArudiR. L., BielskiB. H. J., AllenA. O.. Search for singlet oxygen luminescence in the disproportionation of HO₂/O₂[J]. Photochem Photobiol, 1984, 39(4): 703-709

[14] JacksonP. E.. Capillary ion analysis: principles and applications[J]. Chem Aust, 1993, 60(1/2): 165-170

[15] HaddadP. R., HarakuweA. H., BuchbergerW.. Separation of inorganic and organic anionic components of Bayer liquor by capillary zone electrophoresis I: Optimisation of resolution with electrolyte-containing surfactant mixtures[J]. J Chromatogr A, 1995, 706(1/2): 571-578

[16] HarakuweA. H., HaddadP. R., JacksonP. E.. Quantitative determination of oxalate in Bayer liquor by capillary zone electrophoresis[J]. J Chromatogr A, 1996, 739(1/2): 399-403

[17] ChovancekM., ChooP., MackaM.. Development of a fully buffered molybdate electrolyte for capillary electrophoresis with indirect detection and its use for analysis of anions in Bayer liquor[J]. Electrophoresis, 2004, 25(3): 437-443

[18] BarnettN. W., LewisS. W., PurcellS. D., et al. . Determination of sodium oxalate in Bayer liquor using flow-analysis incorporating an anion exchange column and tris(2,2-bipyridyl)ruthenium(II) chemiluminescence detection[J]. Analytica Chimica Acta, 2002, 458(1/2): 291-296

[19] WHELAN T J, WILSON M A, KAMALI KANNANGARA G S. HPLC investigation of humics found in Bayer liquors[J]. Australian Organic Geochemistry Conference, 2002, (12/15): 77–78.

[20] WhelanT. J., Kamali KannangaraG. S., WilsonM. A.. Increased resolution in high-performance liquid chromatograph spectra of high-weight organic components of Bayer liquors[J]. Ind Eng Chem Res, 2003, 42(26): 6673-6681

[21] WhelanT. J., ShallikerR. A., McintyreC., et al. . Development of a multidimensional high-performance liquid chromatograph(HPLC) separation for Bayer humic substances[J]. Ind Eng Chem Res, 2005, 44(14): 3229-3237

[22] POWER G P, TICHBON W. Sodium oxalate in the Bayer process: its origin and effects[C]// Proceedings of the 2nd International Alumina Quality Workshop. Perth: Australia, 1990.