Processing of perovskite concentrate by ammonium hydrodifluoride

Крысенко, Г. Ф.; Эпов, Д. Г.; Медков, М. А.; Sitnik, P. V.; Nikolaev, A. I.

doi:10.1134/s0040579516040163

Cited by 6 publications

(8 citation statements)

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“…The thermogravimetric study showed that interaction of perovskite concentrate with NH 4 HF 2 ( Fig. 1, a) started in the dry mixture at 100 o C with heat liberation; above 120 o C one could observe the endothermic effect of the fluorination agent fusion, and further, the reaction proceeded in the melt with the maximum rate at 155 o C and was completed at 200 o C [6]. Interaction of loparite concentrate with NH 4 HF 2 also starts in the dry mixture at 100 o C with heat liberation, above 121 o C the endothermic effect of the fluorinating agent melting is added to this process, and further, the reaction proceeds in the melt with the maximum rate at 165 o C and is completed at 205 o C (Fig.…”

Section: Resultsmentioning

confidence: 99%

Complex processing of titanium-rare metal raw material

et al. 2018

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The paper is devoted to investigation of the complex processing of titanium-rare metal raw materials with ammonium hydrodifluoride. It is stated that fluorination of the main components of the mineral raw materials with ammonium hydrodifluoride proceeds with formation of complex ammonium fluorometallates and simple fluorides. It is showed that in the process of aqueous leaching of the fluorinated mineral raw material niobium and tantalum completely pass into solution together with titanium, iron, and silicon fluoroammonium salts while all the rare-earth elements stay in the insoluble residue as complex fluorosodium salts together with CaF2. The method of separation of the fluoroammonium salts with obtaining marketable products and isolation of the rare-earth elements from the insoluble residue is offered.

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Section: Resultsmentioning

confidence: 99%

Complex processing of titanium-rare metal raw material

et al. 2018

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“…However, complex technologies for treatment perovskite have already been developed for the Afrikanda deposit. They are based on the production of pigment titanium dioxide, and REE as the byproducts (Krysenko et al 2016; Krysenko et al 2016). The process of beneficiation of perovskite ore by flotation method with phosphoric acid has also been known for a long time (Bulatovic and Wyslouzil 1999).…”

Section: Technologies Of Ree Minerals Processingmentioning

confidence: 99%

Rare earths of the Murmansk Region, NW Russia: minerals, extraction technologies and value

Kalashnikov

Коноплева

Danilin

2022

Applied Earth Science

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There are rich deposits of rare earth elements (REE) in the Murmansk region, Russia (approximately 14 194 kt of REE 2 O 3 ). At the moment only one of REE deposits are being extracted and processed, the Lovozero Loparite deposit. The main purpose of this article is to estimate the expected value of existing REE resources in the Murmansk region and to make an overview on actual technologies for the extraction and processing of REE from ore minerals. Based on these data, the authors propose a direction for the development of REE industry in the region, namely extraction of REE from minerals already mined (apatite of the Khibiny deposits and baddeleyite of the Kovdor deposit); optimisation or development of mineral processing technologies of eudialyte (the Lovozero Eudialyte deposit) and perovskite (the Afrikanda deposit); carrying out exploration works at the Keivy Zr-REE ore occurrences and developing processing and technologies for these ores.

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“…The fluorination reaction of ilmenite or perovskite should be carried out under high temperature and high pressure. The Ti leaching rate is only about 78% at 160 • C for 120 min in the leaching of perovskite by NH 4 HF 2 [25].…”

Section: Introductionmentioning

confidence: 95%

“…The fluorination method was proposed to prepare titanium dioxide, ferric oxide, or calcium fluoride from ilmenite or perovskite [24,25]. The leaching agent of fluorination method is NH 4 HF 2 or NH 4 F. The reaction temperature of fluoride leaching process is about 100 • C, which is much lower than that of chlorination process and sulfuric acid process.…”

Section: Introductionmentioning

confidence: 99%

Fluoride Leaching of Titanium from Ti-Bearing Electric Furnace Slag in [NH4+]-[F−] Solution

Zheng

Guo

Chen

et al. 2021

Metals

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The effects of F− concentration, leaching temperature, and time on the Ti leaching from Ti-bearing electric furnace slag (TEFS) by [NH4+]-[F−] solution leaching process was investigated to reveal the leaching mechanism and kinetics of titanium. The results indicated that the Ti leaching rate obviously increased with the increase of leaching temperature and F− concentration. The kinetic equation of Ti leaching was obtained, and the activation energy was 52.30 kJ/mol. The fitting results of kinetic equations and calculated values of activation energy both indicated that the leaching rate of TEFS was controlled by surface chemical reaction. The semi-empirical kinetics equation was consistent with the real experimental results, with a correlation coefficient (R2) of 0.996. The Ti leaching rate reached 92.83% after leaching at 90 °C for 20 min with F− concentration of 14 mol/L and [NH4+]/[F−] ratio of 0.4. The leaching rates of Si, Fe, V, Mn, and Cr were 94.03%, 7.24%, 5.36%, 4.54%, and 1.73%, respectively. The Ca, Mg, and Al elements were converted to (NH4)3AlF6 and CaMg2Al2F12 in the residue, which can transform into stable oxides and fluorides after pyro-hydrolyzing and calcinating.

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Processing of perovskite concentrate by ammonium hydrodifluoride

Cited by 6 publications

References 0 publications

Complex processing of titanium-rare metal raw material

Complex processing of titanium-rare metal raw material

Rare earths of the Murmansk Region, NW Russia: minerals, extraction technologies and value

Fluoride Leaching of Titanium from Ti-Bearing Electric Furnace Slag in [NH4+]-[F−] Solution

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