DE1592169A1 - Enrichment process for the simultaneous production of a lanthanum-europium nitrate solution and a fluorine-containing cerium oxide - Google Patents

Description

Bipl-Ing. F.Weickmann, Dr. Ing.A / Weickmann, Dipl-Ing. H. Weickmann Dipl.-Phys. Dr. K. Fincke Patent Attorneys 1592169

J .-- J [■ 8 MÜNCHEN 27, MOHLSTRASSE 22, CALL NUMBER 483921/22

Γίί-.aa i / .ir.ao; it.TGiie .filr ^ jtic ^ ptof f-- ^ rke Aktiengesellschaft ■ 322? T r ο = ■: t ^; , - ■: Γ j

Dr. Expl.

for the simultaneous production of a uanthan iuropium nitrate lion /]; and a fluorine-containing cerium

It is already known to treat fluorine-containing compounds of the rare earths with o "ursn, whereby the fluorine-containing compounds denatured ostnäsite or secondary products ΰιβκ P.yroohlors come into consideration, which in: 1 processing of the mineral by PLui3s ^{! I.} ureeinv / MPACT fluorhalti ^ · ^ e / are orden. In the SöureaufpchluTS vird addition to the total rare iiirden also daa fluorine released since '/ ierv / erti ^ cerium forms fluorides löslicho complex compounds. subsequent inv / MPACT of z L SChv / efeldioxyd on the solution containing the rare earths, the fluorine can be precipitated again with part of the rare earths. Enrichment of certain rare earths, κ.ΰ, the Ger is aui. ' The above-mentioned approach cannot be achieved.

0QS323 / U36

- 2 BATH ORIGINAL

¥ 111, on the other hand, if one has to separate it completely, that has to be done first Fluorine removed. -Earth, vac e.g. with the help of concentrated Sulfuric acid is achieved. Then the rare earths are precipitated as hydroxides and the ger contained in them is oxidized to the tetravalent level at an elevated temperature Subsequent reaction product with dilute acids, e.g. Treated nitric acid, the tetravalent ger remains largely undissolved, while almost all of the lanthanum and the remaining rare earths go into solution. This way of working is lengthy, requires the use of considerable amounts of "chemicals and causes the removal of the fluorine. The retention of the fluorine in cerium is particularly useful for metal-surgical, however, see application as very desirable.

If you use sulfuric acid instead of nitric acid, this will be the case Cerium concentrate with sulfates that are difficult to remove contaminated. In addition, this sulphate content interferes with the application possibilities of the cerium concentrate in metallurgy.

^ The present invention is based on the object fluorine-containing rare earth compounds for the purpose of extraction a lanthanum nitrate solution low in oil and fluorine can be easily produced and the fluorine largely combined to be enriched with the cerium.

According to the invention, this object is achieved in that fluorine-containing compounds of the rare earths are treated with an insufficient amount of nitric acid for complete dissolution of the rare earths at 40-115 ° C and the 009828/1436

BATH. ORIGINAL - 3 "

Reaction mixture separates in a known manner.

It has proven to be expedient to feed the fluorine-containing compounds of the rare earths in countercurrent to the nitric acid, whereby the acid is largely utilized and the lanthanum nitrate solution is only slightly acidic, ζ.Έ, has a pH value of 3, leaves the plant.

The countercurrent flow can take place, for example, according to the following scheme:

ENT,

Ce-rich Se.E "Oxyd-Fluor id

Ce- and Ρ-poor La-i) u-nitrate solution

Bastnnsit

i) The solid / liquid separation does not have to be done by filtration; it can e.g. also be decanted. This makes it easier to carry out the process continuously.

It may be necessary to dilute with prior to separation. water to recommend. A particular advantage of the method of operation according to the invention is that the europium also dissolves with the lanthanum enriched in the Fitrat solution. The desired degree of purity is set by countercurrent flow in a multi-stage process. In addition, the significantly lower consumption of chemicals and the greatly reduced duration of the process are noteworthy.

Analysis of the commercially available, annealed bastnäsite:;. · ■ ----

- 4 - "■ '■' ■■■■ - '■'; ■■■■

009828 / U36

BAD ORiGINAt

~ 4 -

90
0 , 2
, 7 fo SE-0xyd + TIi0 ₂
Loss on ignition. in the
<0 _r 2 Total oxjd: in the vie
Step) ,1 fo F. <b, 2 f *? 2 ° 3 52.2 i » La ₂ O ₅ 51.2
4 »t $ * CeO ₂ (of which 92.5 fo
f * Pr _o 0 «tetravalent.

0.9

example

2000 parts by weight Annealed bastnäsite are ¥ water in 860 teaspoons slurried, with stirring 1650 vol.- tl. 57 Salty peracid added and heated to 70 G for several hours. The reaction mixture is then poured into 3000 vol. Poured water and filtered, the filter residue calcined.

1060 parts by weight are obtained calcined residue and 7500 parts by volume Piltrat.

Analysis of the filtrate ;

Analysis of the calcined residue;

116.0 parts by weight J3E oxide + ThO ₂ 88.5 fo SB oxide + ThO,

/ 1000 parts by volume 10.1 ^ P

$ 0.5> loss on ignition

In total oxy d: 65.0 fo Le ₂ O " 9.4 $ _{CeO 2}

O,

In the total oxide 3 »5 fo La ₂ O 91» 0 fo OeO ₂

009828 / U36

BATH

. '■■■ - -5 -

TTm the advantages of the counter-current flow already described or fluorine-containing compounds of the rare earths to nitric acid To show, the ITiltrate is still fresh, annealed Bastnasite treated. · -, ■

To 7; 85 Vol.-Ti. The filtrate is 200 parts by weight. Annealed bastnesite was added, heated to 80 ° for 3 hours and then filtered. The pilter residue is' annealed.

175 parts by weight calcined residue and 1100 vol.- tl. Urgent advice received.

Analysis of the urgency ; · ■ ■ '

106.5 parts by weight SE-0xyd + Th0 ₂ ·.

/ 1000 VoI.-Tl.

pH = 3

'' Analysis: of the annealed residue:

90.0 fo RE oxide +

In ffesamtoxyd:

72.0 ^ La ₂ O, in Gesamtoxyd: 20.1 2.6 ° / o GeO ₂ - 65f5

As shown in the analysis of the filtrate, a further A is carried out tion of Isnthan with simultaneous decrease in Cer <*> pro rata. The residue obtained by this procedure is in the countercurrent process either with 'fresh saltpeter · » acid or ralt nooh excess acid, containing Iia- "Eu" <? Hitrate solution further treated.

QO9028 / U36r:

-k.

Claims (1)

«.6 patent claims" -ι r η --ι ι r »η 1. Process for the treatment of fluorine-containing compounds of the rare earths for the purpose of producing a lanthanum "europium nitrate solution and a fluorine-containing cerium oxide by reacting optionally thermally pretreated diXfceäfl fluorine-containing compounds of the rare earths with acid in deficit at elevated temperature, characterized in that fluorine-containing compounds of the rare earths ground with an insufficient for complete dissolution of the rare earths amount of nitric 'acid at 40 "115 ⁰ O treated and / else separating the reaction mixture in a known V.
2. ^ Method according to claim 1, characterized in that the fluorine-containing rare earth compounds in countercurrent led to nitric acid. BADOFHGINAL.- ..