DD282244A5 - METHOD FOR OBTAINING NICKEL FROM NICKEL-CONTAINING IRON VANADATE - Google Patents

Abstract

The invention relates to a process for obtaining pure nickel compounds from nickel-containing iron vanadates obtained in the processing of Erdoelrueckstaenden or spent catalysts. The aim of the invention is a method which allows, at low cost of energy and chemicals environmentally friendly read out of the vanadates nickel and precipitated as pure compounds while the residue is activated for subsequent nascent chemical recovery of the vanadium. According to the invention, the object is achieved by treating the nickel-containing iron vanadate in a liquid suspension, optionally in the presence of small amounts of additional oxidizing agents, such as chlorates, at 20 ° C. After separation of extracted iron and vanadium at p * can be obtained from the solution, a pure nickel compound, the solution contains up to 0.3 mgl 1 nickel and optionally 0.2 to 0.3 gl 1 potassium chlorate, which by reaction with * eliminated {procedure; Rueckgewinnung; Nickel; Nickel compounds; iron vanadate; Erdoelrueckstaende; Wertstoffrueckgewinnung; spent catalysts}

Description

Field of application of the invention

The invention relates to a process for obtaining pure nickel compounds from nickel-containing iron vanadates, as obtained in the processing of residues of the petroleum industry.

Characteristic of the known state of the art

For the processing of nickel-containing products, in particular of nickel-containing ores, technical processes are already in use (Ullmanns Encyclopadie der technischen Chemie, eds. Wilhelm Foerst, Munich-Berlin-Vienna, Urban and Schwarzenberg, 3rd and 4th editions, Gmelin's Handbook of Inorganic Chemistry, 8th edition, nickel, part Al, 1967, Verlag Chemie GMBH, Weinheim / Bergstrasse).

Known processes are the MOND process (extraction of nickel by nickel carbonyl formation), the SHERRITT-GORDON process (leaching with ammonia under pressure, the INCO process (leaching with ammonia / ammonium compounds), the NICARO process (ammoniacal leaching, unbroken air introduction). , the SILL process (alkaline digestion followed by sulphurous leaching) and leaching with mineral acids.

The processes for leaching the nickel from ores or other nickel-containing products often require mechanical and / or thermal (roasting) pretreatment. Thus, technically the reduction-roast and ammonium carbonate leaching method for ores has proven itself.

A disadvantage of the roasting process, which often precedes the ammoniacal leaching, is the high energy consumption (DE 2300172, US 4329192, JP B81028). Although processes which separate nickel via the carbonyl lead to qualitatively pure nickel, they also consume considerable amounts of energy for carbonyl formation (DD 18178, GB 1300445). In the case of the present nickel-containing iron vanadate, the ammoniacal leaching provides unsatisfactory yields. Leaching with ammonium chloride solution (100 g / l) gives a nickel yield of 70-75%. In this case, vanadium and iron are extracted, which makes it difficult to prepare the solution.

The use of mineral acids often leads to good yields, depending on the material. However, the disadvantage here appears to be the co-extraction of further metals present in the material, so that the work-up of the solutions is likewise associated with considerable problems of metal separation. Also known is the extraction of nickel with organic extraction ribs (US 4010237, DE 3707261). Disadvantages of these processes include extraction at elevated temperatures and the cost of the extractant.

According to DE 3707 261, the chelate extraction preferably serves only for metal enrichment in the solutions, and further processes are required for the separation and precipitation of the extracted metals.

A recovery of nickel from products which also contain vanadium in addition to other elements is disclosed in the patents US 4443415, DE 340235G and DE 3521 092.

US Pat. No. 4,443,415 describes a process for recovering vanadium and nickel from petroleum coke containing 50% carbon to 10% iron, vanadium, nickel and sulfur, nickel being present as a sulfur compound.

A disadvantage of this method is the energy required to achieve optimum pressure and temperature conditions for the treatment of the stirred from petroleum coke and sodium carbonate solution sludge in the autoclave.

The process for processing residues containing nickel and vanadium (eg petroleum ash, catalysts) according to DE 3420356 provides mechanical comminution of the material, mixing with alkali compounds and heating in an oxidizing atmosphere furnace to melt the alkali compounds. With sulfur carriers, vanadium-poor nickel brick and nickel-poor vanadium slag are formed, taken off separately and fed to further processing.

This process also requires a considerable amount of energy to reach the required melting temperature.

Furthermore, there are products that need to be subjected to further processing steps.

A method for the separation of metal compounds by reduction from dusts, sludges, heavy oil ash is set out in DE 3 210092. In this method, the disadvantages in the number of processing steps and thus a high equipment and equipment expense, on the other hand by the digestion with sulfuric acid iron, nickel and vanadium are brought into solution, so that the precipitation of iron is likely and thus formed contaminated ammonium polyvanadate becomes.

Furthermore, the production of nickel from nickel-containing iron vanadate with chlorate solutions by mechanical stirring is known. However, it must work with a larger excess of chlorate v / earth, and it remains z. Example, when using a potassium chlorate solution of 100g / l under the specified conditions 19-22g / l potassium chlorate in the solution. These chlorate solutions represent a significant environmental impact and must be eliminated by further process steps.

Object of the invention

The aim of the invention is to provide a method for the production of nickel from nickel-containing iron vanadate, which ensures high nickel application with low energy and equipment expense and minimizing the use of chemicals in as few process steps as possible and with low Unweitbelastung.

Presentation of the invention

The invention is based on the technical object of extracting nickel from nickel-coated iron vanadate with good yields, while keeping the coal extraction of iron and vanadium as low as possible and making the process environmentally friendly by using little chemicals.

According to the invention, this object is achieved in that the to be worked up nickel-containing Eisenvanadat an extraction with water or dilute chlorate solutions under compressed air in a temperature range of 5 to 100 ⁰ C, preferably at 2O ⁰ C, (and under normal pressure) is subjected to a pH Value of 5-5.7 is adjusted to precipitate iron and vanadium, optionally the solution is oxidized, then a filtration takes place, from the filtrates by known methods pure nickel compounds are obtained and activates the leaching residue for the subsequent wet chemical recovery of the vanadium becomes.

Even at the extraction with water and two hours of introduction of compressed air (0.45 MPa) can be at 2O ⁰ C 84% of the nickel spend.

When using potassium chlorate solutions with a mass concentration of 5 g · Γ 'in place of water, 92-94% nickel is extracted. By favorable introduction of compressed air mixing of the products, so that an additional mechanical mixing is eliminated by stirring.

When using the above-mentioned potassium chlorate solution (5 g · Γ ¹ ) remain in the filtrate only 0.2-0.3g · Γ ¹ potassium chlorate, while the main proportion is converted to chloride.

The resulting solution from the Chlorailaugung, which still contains small amounts of iron and vanadium in addition to nickel is adjusted with an alkaline solution to pH = 5-5.7, with 99.9% vanadium and 99.5% iron and 8-10 % Nickel are precipitated. The resulting sludge can again be fed to the nickel nuclide and from the filter can be obtained by known methods nickel in the form rsiner compounds.

The solutions of the leaching with water are expediently oxidized to complete vanadium and iron separation at pH = 5-5.7.

embodiments example 1

Per 100 g of nickel-containing iron vanadate (V: 10%, Ni: 2.9%, Fe: 19%, S: 2%, H ₂ 0: 34%) are suspended in 200 ml of water and 1 h under 0.45 MPa compressed air at various temperatures initiated. This results in the following extraction yields of the metals of interest:

δ Rn; Ry Rf, pH

⁰ C%%

20 82.2 7.8

40 83.8 8.1

60 84.7 7.9

80 85.1 7.8

100 84.2 7.4 At elevated temperatures, the extraction yields of nickel are only 2-3% higher than those at 20 ^° C.

Example 2

In each 100g in 200 ml of water suspended nickel-containing iron vanadate (V: 10%, Ni: 2.9%, Fe: 19%, S: 2%, H ₂ O: 34%) is at 2O ⁰ C compressed air (0.45MPa) initiated. The extraction yields are:

% the filtrates 2.1 2.4 2.1 2.3 2.1 2.3 1.8 2.2 1.7 2.2

Time rn; Rv Sharpness min % % % 10 78.2 6.8 1.6 30 81.3 8.2 1.8 60 82.2 7.8 2.1 120 84.1 7.6 2.1 180 84.0 8.1 2.1 420 83.2 8.4 2.1

Example 3

10 g of nickel-containing iron vanadate (V: 10%, Ni: 2.9%, Fe: 19%, S: 2%, H ₂ O: 34%) in 200 ml of a potassium chlorate solution with a mass concentration of 5 g / l 2 hours with compressed air ( 0.45M Pa), 2.7 g of nickel (93%), 0.12 g of vanadium (1.2%) and 0.3 g of iron (1.6%) are dissolved in solution, the pH of the solution is 1 , the ninth

Example 4

A solution (filtrates as obtained in the extraction of Example 3) of the composition 11.4 g · Γ 'of nickel, 1.5 g of iron and 0.6 g of vanadium, pH = 1.9 is adjusted to pH = 5 5. 99.9% of vanadium, 99.5% of iron and 8.5% of the nickel are precipitated, and the precipitated sludge can be re-fed to the nickel extraction from the raw material (10.4 g × ¹ nickel, 0, 0075 g × ¹ iron and not more than 0.0006 g × ¹ vanadium) pure nickel hydroxide can be precipitated by adjusting the solution to pH = 11. Up to 0.5 mg × nickel is left in the solution.

Claims (5)

1. A process for obtaining pure nickel compounds from nickel-containing iron vanadates, characterized in that the iron vanadate under introduction of an oxygen-containing gas at a temperature of 5 ... 100 ⁰ C is subjected to leaching with water or solutions of oxidizing agents, a pH of 5 Is set to 5.7, followed by filtration, wherein pure nickel compounds can be obtained from the filtrate in a manner known per se, and the leaching residue is activated for subsequent recovery of further valuable substances. 2. The method according to claim 1, characterized in that the leaching occurs without mechanical pretreatment and without mechanical stirring. 3. The method according to claim 1 and 2, characterized in that the oxidizing agents are chlorates. 4. The method according to claim 1-3, characterized in that the oxygen-containing gas is air. 5. The method according to claim 1-4, characterized in that the leaching is carried out at 20 ° C.