Highly efficient desorption and reuse of fatty acid collectors adsorbed on mineral surface: A case study of scheelite

Abstract

Flotation is the most common method to recover valuable minerals by selective adsorption of collectors on target mineral surfaces. However, in subsequent hydrometallurgy of mineral flotation concentrates, the adsorbed collectors must be desorbed since it can adversely affect the efficiency of metallurgical process and produce wastewater. ZL, as a fatty acid mixture, is a typical industrially used collector for scheelite flotation in China. Sodium oleate (NaOL) has similar fatty acid group as ZL. In this study, the desorption behavior of NaOL/ZL from scheelite surface by a physical method of stirring at a low temperature was investigated. NaOL desorption tests of single mineral showed that a desorption rate of 77.75% for NaOL from scheelite surface into pulp was achieved in a stirring speed of 2500 r/min at 5°C in a neutral environment. Under the above desorption condition, in the pulp containing desorbed collector by adding extra 30% normal NaOL dosage, the scheelite recovery reached about 95% in the single mineral flotation test. Desorption and reuse of ZL collector for the flotation of real scheelite ore showed only a 75% normal dosage of ZL could produce a qualified rough concentrate. The atomic force microscope (AFM) tests showed that after desorption treatment of low temperature and strong stirring, the dense strip-like structure of NaOL on the scheelite surface was destroyed to be speck-like. Molecular dynamics simulations (MDS) demonstrated that the adsorption energy between NaOL and scheelite surface was more negative at 25°C (−13.39 kcal/mol) than at 5°C (−11.50 kcal/mol) in a neutral pH, indicating that a low temperature was beneficial for the desorption of collector from mineral surface. Due to its simplicity and economy, the method we proposed of desorption of collector from mineral surface and its reuse for flotation has a great potential for industrial application.

Keywords

desorption / reuse / flotation / scheelite concentrate / fatty acid collector

References

[1] MengJ, TabosaE, XieWG, RungeK, BradshawD, ManlapigE. A review of turbulence measurement techniques for flotation. Miner. Eng., 2016, 95: 79

[2] Z.K. Miao, L.M. Tao, J.J. Wang, et al., Selective separation of fluorite from scheelite using N-decanoylsarcosine sodium as a novel collector, Minerals, 12(2022), No. 7, art. No. 855.

[3] GaoZY, DengJ, SunW, et al.. Selective flotation of scheelite from calcite using a novel reagent scheme. Miner. Process. Extr. Metall. Rev., 2022, 43(2): 137

[4] LiaoRP, WenSM, FengQC, DengJS, LaiH. Activation mechanism of ammonium oxalate with pyrite in the lime system and its response to flotation separation of pyrite from arsenopyrite. Int. J. Miner. Metall. Mater., 2023, 30(2): 271

[5] Y. Foucaud, M. Badawi, L. Filippov, I. Filippova, and S. Lebègue, A review of atomistic simulation methods for surface physical-chemistry phenomena applied to froth flotation, Miner. Eng., 143(2019), art. No. 106020.

[6] LiuGY, YangXL, ZhongH. Molecular design of flotation collectors: A recent progress. Adv. Colloid Interface Sci., 2017, 246: 181

[7] J.J. Wang, Z.Y. Gao, and W. Sun, Desorption and reuse of Pb-BHA-NaOL collector in scheelite flotation, Minerals, 13(2023), No. 4, art. No. 538.

[8] LyuRP, ZhiMF, JiangZY, YuanZC, ZhuLL, YuW. Study on the thermal activation of persulfate to remove organic agents from monazite flotation concentrates. Nonferrous Met. Eng., 2023, 13(5): 68

[9] LiuRQ, LuHY, XuZJ, et al.. New insights into the reagent-removal mechanism of sodium sulfide in chalcopyrite and galena bulk flotation: A combined experimental and computational study. J. Mater. Res. Technol., 2020, 9(3): 5352

[10] KangJH, ChenC, SunW, et al.. A significant improvement of scheelite recovery using recycled flotation wastewater treated by hydrometallurgical waste acid. J. Cleaner Prod., 2017, 151: 419

[11] KhosoSA, HuYH, LüF, GaoY, LiuRQ, SunW. Xanthate interaction and flotation separation of H₂O₂-treated chalcopyrite and pyrite. Trans. Nonferrous Met. Soc. China, 2019, 29(12): 2604

[12] TaoLM, WangJJ, LiaoDJ, et al.. Efficient desorption and reuse of collector from the flotation concentrate: A case study of scheelite. Int. J. Miner. Metall. Mater., 2024, 31(11): 2435

[13] HirajimaT, MikiH, SuyantaraGPW, et al.. Selective flotation of chalcopyrite and molybdenite with H₂O₂ oxidation. Miner. Eng., 2017, 100: 83

[14] IwasakiI, CookeSRB. The decomposition of xanthate in acid solution. J. Am. Chem. Soc., 1958, 80(2): 285

[15] ZhangCH, HeTS, LiH, BuXZ. Adsorption thermodynamics and kinetics of xanthate at chalcopyrite surface based on ultraviolet spectrophotometry. Spectrosc. Spectral Anal., 2019, 39(10): 3172

[16] H.Y. Lu, C.Y. Qian, S.G. Luo, Y.G. Zhu, R.Q. Liu, and M.R. Wu, Study on the influence and mechanism of polyferric sulfate on COD removal and reuse of scheelite flotation wastewater, Miner. Eng., 191(2023), art. No. 107940.

[17] HanC, WeiDZ, GaoSL, ZaiQX, ShenYB, LiuWG. Adsorption and desorption of butyl xanthate on chalcopyrite. J. Mater. Res. Technol., 2020, 9(6): 12654

[18] W.G. Zhou, K. Liu, L. Wang, B.N. Zhou, J.J. Niu, and L.M. Ou, The role of bulk micro-nanobubbles in reagent desorption and potential implication in flotation separation of highly hydrophobized minerals, Ultrason. Sonochem., 64(2020), art. No. 104996.

[19] TangH, TaoJM, RuzsinszkyA, PerdewJP. van der Waals correction to the physisorption of graphene on metal surfaces. J. Phys. Chem. C, 2019, 123(22): 13748

[20] YeQJResearch on the Demedication Process and Mechanism of Flotation Concentrate of Ilmenite in Panzhihua, 2015, Kunming, Kunming University of Science and Technology: 7

[21] W.W. Sheng, T.C. Wang, D.H. Wan, and J.T. Jiao, The technological transformation and practice of the mineral processing technology in Xinjiang Ashele copper mine, Multipurpose Util. Min. Resour., (2009), No. 4, p. 5.

[22] T. Peng, L.M. Tao, J.J. Wang, et al., Selective flotation separation of scheelite from calcite using hexamethylenediamine tetramethylene phosphonic acid as a novel depressant, J. Mol. Liq., 402(2024), art. No. 124569.

[23] WuHY, QiGR, LinH. Application of a new collector ZL in scheelite flotation. China Tungsten Ind., 2019, 34(5): 25

[24] ZengQJ, LinRX, ZhangXH. Researches and applications of scheelite flotation with ZL collector. Mater. Res. Appl., 2007, 1(3): 231

[25] XuLW, LiangY, XuG, et al.. Decomposition mechanism of scheelite based on sodium bisulfate roasting. J. Sustain. Metall., 2023, 9(3): 1061

[26] DongLY, JiaoF, QinWQ, ZhuHL, JiaWH. Activation effect of lead ions on scheelite flotation: Adsorption mechanism, AFM imaging and adsorption model. Sep. Purif. Technol., 2019, 209: 955

[27] WangZM, FengB, ChenYG. Flotation separation depressants for scheelite and calcium-bearing minerals: A review. Int. J. Miner. Metall. Mater., 2023, 30(9): 1621

[28] J.A. Aguilar-Torrejón, P. Balderas-Hernández, G. Roa-Morales, C.E. Barrera-Díaz, I. Rodríguez-Torres, and T. Torres-Blancas, Relationship, importance, and development of analytical techniques: COD, BOD, and, TOC in water: An overview through time, SN Appl. Sci., 5(2023), No. 4, art. No. 118.

[29] GaoZY, XieL, CuiX, HuYH, SunW, ZengHB. Probing anisotropic surface properties and surface forces of fluorite crystals. Langmuir, 2018, 34(7): 2511

[30] L.M. Tao, G.Y. Xiang, Z.K. Miao, et al., Method and mechanism of reverse flotation for dephosphorization of spodumene concentrate using sodium alginate as a depressant, J. Cleaner Prod., 451(2024), art. No. 142171.

[31] J.Y. He, W. Sun, H.B. Zeng, R.H. Fan, W. Hu, and Z.Y. Gao, Unraveling roles of lead ions in selective flotation of scheelite and fluorite from atomic force microscopy and first-principles calculations, Miner. Eng., 179(2022), art. No. 107424.

[32] J.X. Zhang, C. Yang, F.S. Niu, and S.L. Gao, Molecular dynamics study on selective flotation of hematite with sodium oleate collector and starch-acrylamide flocculant, Appl. Surf. Sci., 592(2022), art. No. 153208.

[33] Z.H. Shen, Q. Zhang, X.B. Li, and Q.L. Chen, Adsorption behavior and wettability of rhodochrosite surface: Effect of C18 fatty acid unsaturation, Minerals, 10(2020), No. 10, art. No. 905.

[34] HuangZQ, ShuaiSY, BurovVE, et al.. Adsorption of trisiloxane surfactant for selective flotation of scheelite from calcite at room temperature. Langmuir, 2022, 38(29): 9010

[35] Y.H. Wang, G.C. Pan, H.R. Chu, D.F. Lu, and X.Y. Zheng, Flotation separation of scheelite from calcite using sulfonated naphthalene–formaldehyde condensate as depressant, Minerals, 12(2022), No. 5, art. No. 517.

[36] X.K. Li, H.Y. He, Y. Zhang, Y. Wu, and Z.H. Guan, Flotation separation of scheelite from calcite using baicalin as a depressant, Colloids Surf. A, 675(2023), art. No. 132006.

[37] Z.H. Guan, K.W. Lu, Y. Zhang, H. Yang, and X.K. Li, Mechanism of manganese ion interaction with the surface of scheelite and calcite and its effect on flotation separation, Colloids Surf. A, 648(2022), art. No. 129397.

[38] Z.M. Ma, X.Z. Shi, L.H. Xu, et al., Selective flotation separation of spodumene from feldspar using a novel mixed anionic/cationic collector NaOL/ND13, Miner. Eng., 201(2023), art. No. 108152.

[39] Q.J. Guan, Y. Sui, W.J. Yu, et al., Deep removal of phosphorus and synchronous preparation of high-strength gypsum from phosphogypsum by crystal modification in NaCl–HCl solutions, Sep. Purif. Technol., 298(2022), art. No. 121592.

RIGHTS & PERMISSIONS

University of Science and Technology Beijing