Experimental validation and numerical model of impurity migration in vacuum distillation for high-purity tellurium production

Abstract

Distillation temperature, as a pivotal thermodynamic parameter in vacuum purification of metals, governs impurity migration through volatility-stratified mechanisms. This study establishes theoretical distribution models for high-volatility (Na and Se), medium-volatility (Fe and Cu), and low-volatility (Ni and Cr) impurities, revealing dual-threshold effects on impurity removal: low-to-medium temperatures (≤550 °C) effectively suppress volatilization, while elevated temperatures promote co-evaporation. At the optimal 550 °C, tellurium purity reaches 5N8 with >90% yield. Spatial fractionation analysis demonstrates high-volatility impurities enriching in the upper condensation zone (X/L<0.25), whereas medium/low-volatility impurities accumulate in the lower zone and residues. Remarkably, residual impurities show significant enrichment versus raw materials—Na 4.04 times, Fe 13.3 times, Cu 53.6 times, Ni 7.17 times, and Cr 15.12 times, through formation of non-volatile compounds/solid solutions. Temperature-space coupling effects drive distinct deviation patterns: fluctuations in high-volatility impurities vs. temperature-progressive deviations in medium/low-volatility species. The impurity concentration of model-experiment deviations (mean±SD) are quantified as: Se 0.265±0.12, Na 0.224±0.02, Cu 0.146±0.06, Fe 0.133±0.13, Cr 0.101±0.07, and Ni 0.122±0.08.

Keywords

vacuum distillation / tellurium / purification / distillation temperature / numerical simulation

References

[1] Wang S, Gong X, Wei J, et al. . Low-dimensional tellurium for electronics, optoelectronics, quantum devices and beyond [J]. Frontiers of Physics. 2025, 20(3): 034401

[2] Liao J-c, Shao H, Zhang Y-x, et al. . Infrared insensor computing based on flexible photothermoelectric tellurium nanomesh arrays [J]. Advanced Materials. 2025, 37(15): e2419653

[3] Han L-l, Yang Z-x, Yang Q, et al. . Visible nonlinear optical properties of tellurium and application as saturable absorber [J]. Optics & Laser Technology. 2021, 137: 106817

[4] Das A, Banik B K. Semiconductor characteristics of tellurium and its implementations [J]. Physical Sciences Reviews. 2023, 8(12): 4659-4687

[5] Zavabeti A, Aukarasereenont P, Tuohey H, et al. . High-mobility p-type semiconducting two-dimensional β-TeO₂ [J]. Nature Electronics. 2021, 4: 277-283

[6] Zha J-j, Shi S-h, Chaturvedi A, et al. . Electronic/optoelectronic memory device enabled by tellurium-based 2D van der Waals heterostructure for insensor reservoir computing at the optical communication band [J]. Advanced Materials. 2023, 35(20): 2211598

[7] Yang Y-f, Xu M-k, Jia S-j, et al. . A new opportunity for the emerging tellurium semiconductor: Making resistive switching devices [J]. Nature Communications. 2021, 12: 6081

[8] Lee C W, Kim S J, Shin H K, et al. . BEOL-compatible tellurium films for optically stimulated and mechanically deformable artificial synapses [J]. Small. 2025, 21(33): 2503131

[9] Tan C-l, Amani M, Zhao C-s, et al. . Evaporated Se_xTe_1−x thin films with tunable bandgaps for short-wave infrared photodetectors [J]. Advanced Materials. 2020, 32(38): 2001329

[10] Zhong J, Wang G, Fan J-l, et al. . Optimization of process on electrodeposition of 4N tellurium from alkaline leaching solutions [J]. Hydrometallurgy. 2018, 176: 17-25

[11] Xu Z-p, Guo X-y, Tian Q-h, et al. . Electrodeposition of tellurium from alkaline solution by cyclone electrowinning [J]. Hydrometallurgy. 2020, 193: 105316

[12] Ha Y C, Sohn H J, Jeong G J, et al. . Electrowinning of tellurium from alkaline leach liquor of cemented Te [J]. Journal of Applied Electrochemistry. 2000, 30(3): 315-322

[13] Li G-l, Li L, Miao R-y, et al. . Research on the removal of impurity elements during ultra-high purification process of terbium [J]. Vacuum. 2016, 125: 21-25

[14] Huang D-x, Jiang W-l, Xu B-q, et al. . Purification of metallurgical-grade crude tellurium based on viscous distillation and gas-phase separation [J]. Transactions of Nonferrous Metals Society of China. 2024, 34(3): 1037-1048

[15] Tian Q-h, He Z-q, Guo X-y, et al. . Research progress of high purity metals prepared by zone melting [J]. The Chinese Journal of Nonferrous Metals. 2023, 33(10): 3321-3336(in Chinese)

[16] Tian Q-h, He Z-q, Xu Z-p, et al. . Experimental analysis of high purity tellurium prepared by zone refining [J]. Metallurgical and Materials Transactions B. 2024, 55(2): 772-781

[17] Zaiour A, Zahraman K, Roumie M, et al. . Purification of tellurium to nearly 7N purity [J]. Materials Science and Engineering B. 2006, 131(1–3): 54-61

[18] Prasad D S, Munirathnam N R, Rao J V, et al. . Purification of tellurium up to 5N by vacuum distillation [J]. Materials Letters. 2005, 59(16): 2035-2038

[19] Ali S T, Prasad D S, Munirathnam N R, et al. . Purification of tellurium by single-run multiple vacuum distillation technique [J]. Separation and Purification Technology. 2005, 43(3): 263-267

[20] Volodin V N, Trebukhov S A, Burabaeva N M, et al. . Melt-gas phase equilibria and state diagrams of the selenium-tellurium system [J]. Russian Journal of Physical Chemistry A. 2017, 91(5): 800-804

[21] Chen G-l, Luo Q-j, Huang D-x, et al. . Clean and efficient sulfuric acid roasting-vacuum thermal reduction process for extracting 4N tellurium from high value-added crude tellurium resource [J]. Journal of Cleaner Production. 2025, 496: 145084

[22] Li H, Zhang J, Li X-g, et al. . Progress in study on thermodynamic properties of phase equilibria using molecular simulation [J]. Chemical Industry and Engineering Progress. 2017, 36(8): 2731-2741

[23] Bale C W, Bélisle E, Chartrand P, et al. . FactSage thermochemical software and databases, 2010 - 2016 [J]. Calphad. 2016, 54: 35-53

[24] Zha G-z, Zhao Y, Luo H, et al. . Evaporation regularities of elemental selenium in the vacuum distillation process [J]. Metallurgical and Materials Transactions B. 2022, 53(6): 3856-3864

[25] Hannikainen K, Gomez D, Pereiro J, et al. . Surface phase metastability during Langmuir evaporation [J]. Physical Review Letters. 2019, 123(18): 186102

[26] Qi Z-l, Dang C, Jia L, et al. . Analytical investigation on heat and mass transfer of r134a/r245fa zeotropic mixture in the liquid film evaporation process [J]. Heat Transfer Research. 2020, 51(17): 1587-1608

[27] Shi S, Li P-t, Meng J-x, et al. . Kinetics of volatile impurity removal from silicon by electron beam melting for photovoltaic applications [J]. Physical Chemistry Chemical Physics. 2017, 19(41): 28424-28433

[28] Arafune K, Yamamoto K, Hirata A. Interactive thermal and solutal Marangoni convection during compound semiconductor growth in a rectangular open boat [J]. International Journal of Heat and Mass Transfer. 2001, 44(13): 2405-2411

[29] Sauer H M, Braig F, Dörsam E. Leveling and drying dynamics of printed liquid films of organic semiconductor solutions in OLED/OPV applications [J]. Advanced Materials Technologies. 2021, 6(2): 2000160

[30] Shao A-c, Hu L-n, Song L, et al. . Revealing mechanism of non-Arrhenius viscosity change in metal melts based on Wulff cluster model [J]. Scripta Materialia. 2023, 234: 115571

[31] Wu L-m, Huang W-c, Wang Y-z, et al. . 2D tellurium based high-performance all-optical nonlinear photonic devices [J]. Advanced Functional Materials. 2019, 29(4): 1806346

[32] Miao G-y, Su N-y, Yu Z, et al. . Doping elemental 2D semiconductor Te through surface Se substitutions [J]. Physical Review Letters. 2024, 133(23): 236201

[33] Grassi A, Irgolic K J, Lombardo G M, et al. . Quantum mechanical studies of organometallic materials containing the Se-Te bond [J]. Phosphorus, Sulfur, and Silicon and the Related Elements. 1998, 136(1): 417-422

[34] Zhou R, Hou Z, Liu Q, et al. . Unlocking the reversible selenium electrode for non-aqueous and aqueous calcium-ion batteries [J]. Advanced Functional Materials. 2022, 32(26): 2200929

[35] Brisson P Y, Darmstadt H, Fafard M, et al. . X-ray photoelectron spectroscopy study of sodium reactions in carbon cathode blocks of aluminium oxide reduction cells [J]. Carbon. 2006, 44(8): 1438-1447

[36] Han C, Zhang X-d, Li T-t, et al. . Carbon nanotubes grown on CuO nanoparticle-decorated porous carbon microparticles for water oxidation [J]. ACS Applied Nano Materials. 2021, 4(11): 12119-12126

[37] Guo M, Zhang C-y, Zhao F-z, et al. . Highly active and stable mixed-phase In₂O₃-supported Ni catalyst for CO₂ hydrogenation to methanol [J]. Chemical Engineering Journal. 2024, 499: 156369

[38] Wang Z, Xi L, Yang Y-k, et al. . Spin-dependent transport properties of CrO₂ micro rod [J]. Nano-Micro Letters. 2014, 6(4): 365-371

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Central South University