| Название |
Neutralization of sulfate solutions in complex treatment of diopsidecontaining processing waste |
| Реферат |
Following respective experimental studies, data were obtained on the qualitative composition of liquid wastes downstream of sulfuric acid treatment of diopside (raffinate). These are 15–25 % solutions of sulfuric acid with the contents of magnesium compounds up to 20 g/l (for pure metal) and aluminum, iron, and titanium contents of up to 20 g/l. A process design solution is proposed for the neutralization of the raffinate after the extraction of scandium compounds, based on the use of magnesium-containing minerals to produce marketable magnesium sulfate heptahydrate (a fertilizer). The possibility of using synthetic brucite (a waste product in the manufacture of refractory materials) as a neutralizing reagent has been established. It has been found that, during the raffinate neutralization, the precipitation rate for iron, aluminum, and titanium hydroxides approaches 100 %. At the same time, a certain part of unreacted magnesium compounds precipitates with the metal hydroxides and may be reused. The resulting solutions are magnesium sulfate brines with the content of magnesium compounds up to 45 g/l for pure metal (and up to 450 g/l for magnesium sulfate heptahydrate). An X-ray phase analysis of the solid product after the vacuum drying of the brines demonstrates that its purity and chemical composition meet the requirements for magnesium-containing mineral fertilizers. The hydroxide precipitate obtained in the process of neutralization was converted to the sulfate form and used as a coagulant to purify model water with the removal of suspended solids (recycled water). The process design solution proposed for the recycling of substandard raffinate may increase the economic efficiency of diopside processing with the output of marketable magnesium sulfate and scandium concentrate. |
| Библиографический список |
1. Tyler G. Rare earth elements in soil and plant systems — A review. Plant and Soil. 2004. Vol. 267, Iss. 1–2. pp. 191–206.
2. Chakhmouradian A. R., Wall F. Rare earth elements: minerals, mines, magnets (and more). Elements. 2012. Vol. 8, No. 5. pp. 333–340.
3. Li G., Ye Q., Deng B., Luo J., Rao M., Peng Z., Jiang T. Extraction of scandium from scandium-rich material derived from bauxite ore residues. Hydrometallurgy. 2018. Vol. 176. pp. 62–68.
4. Weiss D. Developments in aluminum-scandium-ceramic and aluminum-scandium-cerium alloys. Light Metals: Conference proceedings. Springer, 2019. pp. 1439–1443.
5. Peters E. M., Kaya Ş., Dittrich C., Forsberg K. Recovery of scandium by crystallization techniques. Journal of Sustainable Metallurgy. 2019. Vol. 5, Iss. 1. pp. 48–56.
6. Zhang N., Li H.-X., Liu X.-M. Recovery of scandium from bauxite residue — red mud: a review. Rare Metals. 2016. Vol. 35, Iss. 12. pp. 887–900.
7. Smirnov A. L., Titova S. M., Rychkov V. N., Bunkov G. M., Semenishchev V. S., Kirillov E. V., Svirsky I. A. Study of scandium and thorium sorption from uranium leach liquors. Journal of Radioanalytical and Nuclear Chemistry. 2017. Vol. 312, Iss. 2. pp. 277–283.
8. Rychkov V. N., Semenishchev V. S., Mashkovtsev M. A., Kirillov E. V., Kirillov S. V., Bunkov G. M., Botalov M. S. Deactivation of the scandium concentrate recovered from uranium leach liquors. Journal of Radioanalytical and Nuclear Chemistry. 2016. Vol. 310, Iss. 3. P. 1247–1253.
9. Ksenofontov B. S., Kozodaev A. S., Taranov R. A., Vinogradov M. S., Voropaeva A. A., Senik E. V. Development of integrated technologies leaching of rare-earth metals from coal ashes and problem concentration of the solution of these metals. Sovremennye Naukoemkie Tekhnologii. 2016. No. 3–1. pp. 44–49.
10. Wang W., Pranolo Y., Cheng C. Y. Metallurgical processes for scandium recovery from various resources: A review. Hydrometallurgy. 2011. Vol. 108, Iss. 1–2. pp. 100–108.
11. Stepanov S. I., P’ei Kh., Boyarintsev A. V., Giganov V. G., Chekmarev A. M., Aung M. M. Use of machining to increase the recovery of scandium from refractory silicate raw material. Theoretical Foundations of Chemical Engineering. 2018. Vol. 52, Iss. 5. pp. 973–977.
12. Chemistry and technology of rare and trace elements. Pt. 2. Ed. К. А. Bolshakov. 2 ed., rev. and suppl. Мoscow: Vysshaya Shkola, 1976. 360 p.
13. Kuchumov V. A., Shoomkin S. S. Analisys of the chemichal composition of the bearing alloy used in the production of Sm-Co-based permanent magnets. Nauchno-tekhnicheskie Vedomosti SPbPU. 2017. Vol. 23, No 1. pp. 219–225.
14. Agapova Е. А., Chernyshev P. I. Wastewater treatment from heavy metal ions using refractory waste. Proc. of XII International scientific and practical conference of students, postgraduates and young scientists «Youth and scientific and technical progress». In 3 vol. Vol. 3. Stary Oskol: «Assistant Plus», 2019. pp. 4–6.
15. Agapova Е. А., Chernyshev P. I., Kruchinina N. E. Wastewater treatment of galvanic production using mineral adsorbents. Proc. of Interuniversity (with international participation) youth scientific and technical conference (SEARCH–2019). Ivanovo: ISPU, 2019. pp. 318–320.
16. Vinogradov S. S. Environmentally safe galvanic production. 2 еd., rev. and suppl. Мoscow: Globus, 2002. 352 p.
17. ТU 2141-025-32496445-2001. Technical magnesium sulphate.
18. Vasilenko T. A., Koltun A. A. Chemical aspects of the obtaining of iron-containing coagulant-flocculant from electric steel melting slag for wastewater treatment. Solid State Phenomena. 2017. Vol. 265. pp. 403–409. |
