Extracting reaction mechanism analysis of Zn and Si from zinc oxide ore by NaOH roasting method

Abstract

The orthogonal test was used to optimize the reaction conditions of roasting zinc oxide ore with NaOH aiming to comprehensively utilize zinc oxide ore. The optimized reaction conditions were molar ratio of NaOH to zinc oxide ore 6:1, roasting temperature 450 °C, holding time 150 min. The molar ratio of NaOH to zinc oxide ore was the most predominant factor affecting the extraction ratios of zinc oxide and silica. The mineral phase transformations were investigated by testing the phases of specimens obtained at different temperatures. The process was that silica reacted with molten NaOH to form Na₂SiO₃ at first, then transformed into Na₄SiO₄ with temperature rising. ZnCO₃ and its decomposing product ZnO reacted with NaOH to form Na₂ZnO₂. Na₂ZnSiO₄ was also obtained. The reaction rate was investigated using unreacted shrinking core model. Two models used were chemical reaction at the particle surface and diffusion through the product layer. The results indicated that the reaction rate was combine-controlled by two models. The activation energy and frequency factor were obtained as 24.12 kJ/mol and 0.0682, respectively.

Keywords

zinc oxide ore / NaOH roasting method / reaction process / reaction mechanism / kinetics

References

[1] LiY, WangJ-k, WeiC, LiuC-x, JiangJ-b, WangFan. Sulfidation roasting of low grade lead-zinc oxide ore with elemental sulfur [J]. Minerals Engineering, 2010, 23(7): 563-566

[2] SunY, ShenX-y, ZhaiY-chun. Thermodynamics and kinetics of extracting zinc from zinc oxide ore by ammonium sulfate roasting method [J]. Int J Miner Metall Mater, 2015, 22(5): 467-475

[3] ZhaoC-m, ZhaiY-c, ZhangC-m, LiJ-l, LiS-li. Reaction mechanism of molten NaoH decomposing Zn₂SiO₄ in willemite [J]. Journal of Central South University, 2015, 22(4): 1227-1231

[4] YinZ-l, DingZ-y, HuH-p, LiuK, ChenQ-yuan. Dissolution of zinc silicate (hemimorphite) with ammoniaammonium chloride solution [J]. Hydrometallurgy, 2010, 103(1-4): 215-220

[5] ShaoH-w, ShznX-y, SunY, LiuY, ZhaiY-chun. Reaction condition optimization and kinetic investigation of roasting zinc oxide ore using (NH4)2SO4 [J]. International Journal of Mineral Metallurgy and Materials, 2016, 23(10): 1-8

[6] ChenB, ShenX-y, GuH-m, SunY, LiD-g, ZhaiY-c, MaP-hua. Extraction of ZnO from zinc oxide ore by alkali roasting method [J]. CIESC J, 2012, 63(2): 658-661

[7] ShenX-y, SunY, SongJ-q, ZhaiY-chun. Low grade zinc ore by low temperature roasting using (NH₄)₂SO₄ [J]. Chin J Mater Res, 2012, 26(4): 396-401

[8] DouA-c, YangT-z, YangJ-x, WuJ-h, WangAn. Leaching of low grade zinc oxide ores in Ida2—H₂O system [J]. Transactions of Nonferrous Metals Society of China, 2011, 21(11): 2548-2553

[9] LiC-x, XuH-s, DengZ-g, LiX-b, LiM-t, WeiChang. Pressure leaching of zinc silicate ore in sulfuric acid medium [J]. Transactions of Nonferrous Metals Society of China, 2010, 20(5): 918-923

[10] HeS-m, WangJ-k, YanJ-feng. Pressure leaching of synthetic zinc silicate in sulfuric acid medium [J]. Hydrometallurgy, 2011, 108(34): 171-176

[11] EspiariS, RashchiF, SadrnezhaadS K. Hydrometallurgical treatment of tailings with high zinc content [J]. Hydrometallurgy, 2006, 82(12): 54-62

[12] AbkhoshkE, JorjaniE, Al-HarahshehM S, RashchiF, NaazeriM. Review of the hydrometallurgical processing of non-sulfide zinc ores [J]. Hydrometallurgy, 2014, 149(10): 153-167

[13] WangZ-f, PengZ-hui. Characteristic of thermometallurgy of zinc oxide ore [J]. Journal of Jishou University, 1992, 13(6): 116-118

[14] MoradiS, MonhemiusA J. Mixed sulphide oxide lead and zinc ores problems and solutions [J]. Mineral Engineering, 2011, 24(10): 1062-1076

[15] ShaoH-m, ShenX-y, ZhuH-t, ZhaiY-chun. Process and reaction mechanism of roasting low grade zine oxide ore with (NH₄)₂SO₄ [J]. The Chinese Journal of Nonferrous Metals, 2010, 20(6): 1148-1153

[16] YangT-z, DouA-c, LeiC-m, RenJ, LiuZ-zhen. Ligand selection for complex-leaching valuable metals in hydrometallurgy [J]. Transactions of Nonferrous Metals Society of China, 2010, 20(6): 1148-1153

[17] ÇopurM, ÖzmetinC, ÖzmetinE, KocakerimM M. Optimization study of the leaching of roasted zinc sulphide concentrate with sulphuric acid solutions [J]. Chemical Engineering and Processing, 2004, 43(8): 1007-1014

[18] ChenA-l, ZhaoZ-w, JiaX-j, LongS, HuoG-s, ChenX-yu. Alkaline leaching Zn and its concomitant metals from refractory hemimorphite zinc oxide ore [J]. Hydrometallurgy, 2009, 97(34): 228-232

[19] FengL-y, YangX-w, ShenQ-f, XuM-l, JinB-jie. Pelletizing and alkaline leaching of powdery low grade zinc oxide ores [J]. Hydrometallurgy, 2007, 89(34): 305-310

[20] ChenQ-y, LiL, BaiL, HuH-p, LiJ, LiangQ-w, LingJ-hua. Synergistic extraction of zinc from ammoniacal ammonia sulfate solution by a mixture of a sterically hindered beta-diketone and tri-n-octylphosphine oxide (TOPO) [J]. Hydrometallurgy, 2011, 105(34): 201-206

[21] YangS-h, TangM-tang. Thermodynamics of Zn(II)-NH₃-NH₄Cl-H₂O system [J]. Transactions of Nonferrous Metals Society China, 2000, 10(6): 830-833

[22] ChenB, ShenX-y, GuH-m, ShaoH-m, ZhaiY-c, MaP-hua. Comprehensive utilization of low-grade zinc oxide ore by alkaline molten roasting [J]. Multipurpose Utilization of Mineral Resources, 2016, 5: 30-33

[23] LiH-guiMetallurgical principles [M], 2005, Beijing, Science Press

[24] HuaY-xinIntroduction of metallurgical process kinetics [M], 2004, Beijing, Metallurgical Industry Press

[25] ShonH Y, WadsworthM ERate process of extractive metallurgy [M], 1979, New York, Springer

[26] ChenJ-yongHandbook of hydrometallurgy [M], 2005, Beijing, Metallurgical Industry Press

[27] MaR-junPrinciple on hydrometallurgy [M], 2007, Beijing, Metallurgical Industry Press