JP3102331B2 - Method for recovering valuable metals from waste Ni catalyst - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a process for producing a waste Ni catalyst.
The present invention relates to a method for recovering Ni, Co, Mo, and V at a high yield.

[0002]

2. Description of the Related Art Catalysts used for hydrodesulfurization of heavy oil include M
A catalyst in which an o-based catalyst is supported on an alumina carrier is used. Metal components in heavy oil are also attached and contained on the catalyst. At present, Mo and V are industrially recycled from spent catalysts.

[0003] The spent catalyst is soda-fired and subsequently leached with hot water as sodium molybdate Na ₂ MoO ₄ and sodium vanadate NaVO ₃ , and then V is converted to ammonium metavanadate NH ₄ VO ₃ and Mo by salting out. This is a method of recovering molybdate H ₂ MoO ₄ by adding an acid.

[0004] As an adhering component from heavy oil, in addition to V, Ni
There is. Also, some catalysts have Ni and Co added as active components.

However, in the currently used soda-by firing method, Ni and Co are converted to NiAlO ₄ and CoA.
It is known that a solid solution such as 10 ₄ is formed, and cannot be easily leached out by a usual processing method, and is difficult to recover.

[0006] The waste after recovering Mo and V by the soda-by firing method (referred to as Ni waste catalyst herein).
o and V are also partially included. ) To Ni, Co, V, Mo
Separation and recovery are important issues from the viewpoints of not only environmental protection but also prolonging the life of resources and providing a stable supply.

[0007]

SUMMARY OF THE INVENTION The present invention relates to a method for wet pulverization, water leaching and high-temperature dissolving of sulfuric acid from a waste Ni catalyst, which is considered to be difficult to recover valuable metals such as Ni and Co by a normal treatment method. Is to provide a method of recovering Ni, Co, Mo and V at a high yield.

[0008]

According to the present invention, a waste nickel catalyst and water are mixed, wet-pulverized, and sulfuric acid is added to a leaching residue obtained by leaching with water, followed by steaming, and the pH of the obtained solution is adjusted. Thereafter, a valuable metal is recovered from the waste Ni catalyst, wherein a sulfurizing agent is added thereto to recover Ni, Co, and Mo as mixed sulfides.

A preferred embodiment of the present invention will be described below for each step with reference to FIG.

(1) Wet pulverization step In this step, water is mixed with the Ni waste catalyst and pulverized to 100 mesh or less using a ball mill. Preferably 15
Grind to 0 mesh or less (more than 150 mesh). Thereby, sodium molybdate Na ₂ MoO ₄ and sodium vanadate Na ₄ VO _{3 are} contained in the Ni spent catalyst.
Mo and V which are present as water are easily leached with water in the next processing step.

(2) Water leaching step In this step, the Ni spent catalyst, which has been subjected to wet pulverization, has a slurry concentration of 50 to 500 g / l, preferably 100 to 250 g / l.
g / l and a temperature of 70 to 100 ° C, preferably 80 to 1 ° C.
Leaching at 00 ° C., stirring speed of 100 to 1000 rpm, preferably 300 to 500 rpm, at normal pressure for 0.5 to 5 hours, preferably 1 to 3 hours, Mo and V leaching solution containing Ni, Co, Mo , V are obtained. The leaching solution goes to the Mo, V recovery step, and the leaching residue is Ni, Co and M
o to the process of recovering as mixed sulfide.

(3) Sulfuric acid high-temperature dissolving step (steaming step) Ni and Co in the leaching residue after water leaching are solid-solved in the Al carrier like NiAlO ₄ and CoAlO ₄ in the Al carrier as described above. Leaching is difficult with the leaching method. Therefore, in this step, the mixing ratio of sulfuric acid and water is (1: 1) to
(10: 1), preferably using a solution of (1: 1) to (3: 1) to remove the water leaching residue to a slurry concentration of 300 to 1500.
g / l, preferably 500-1,000 g / l, temperature 1
0.2 at 10-170 ° C., preferably 120-130 ° C.
Dissolve at a high temperature for 5 to 2.0 hours, preferably 0.5 to 1.0 hour (this operation is referred to as a steaming step).
This is dissolved in water to obtain a solution of Ni, Co, Mo, and V. At this time, each metal leaching rate is 91% or more.

(4) PH adjustment step This step is carried out in order to efficiently recover Ni, Co and Mo in the solution obtained in the steaming step by performing mixed sulfide.

Here, the pH of the leachate is adjusted to 2.5 to 4.5, preferably 2.7 to 3.6 using calcium hydroxide.
After maintaining the temperature at 40 to 90 ° C., preferably 60 to 80 ° C. for 0.25 to 1.5 hours, preferably 0.5 to 1.0 hour, filtration and separation are performed. Thereby, a part of Fe (III) and Al is separated from the cake after filtration. On the other hand, the filtrate is sent to the sulfurization step.

(5) Sulfidation Step In this step, Ni, Co and Mo are removed from the filtrate after pH adjustment.
To recover as mixed sulfide.

In this step, after the pH is adjusted, a sulfurizing agent such as sodium sulfide or sodium hydrogen sulfide is added in an amount of 1.0 to 2.0 equivalents, preferably 1.1 to Ni, Co and Mo contained in the filtrate. ~ 1.3 equivalents added, temperature 20 ~ 90 ° C,
The reaction is preferably performed at 60 to 80 ° C for 0.25 to 2.0 hours, preferably 0.5 to 1.0 hour. This gives N
i, Co and Mo are recovered as mixed sulfide with a yield of 98% or more.

(6) Impurity Removal Step— (A) The filtrate after the separation of the mixed sulfide contains Al and other trace components, and the pH is preferably 8 to 9.5 using calcium hydroxide. Is neutralized to 8.3 to 8.7 and separated by filtration to obtain a cake and a filtrate.

On the other hand, the liquid after the water leaching step contains mainly M
It contains o and V, and is separated and collected by a conventionally used method (ordinary method).

(7) De-P Step The water leachate contains about 20 to 50 ppm of P. P is removed before entering the V recovery step and the Mo recovery step to prevent contamination. In order to separate this P, 1.3 to 3.0 equivalents of magnesium chloride MgCl ₂ are added to the P, and the mixture is reacted at a temperature of 40 to 50 ° C. for 1 to 2 hours. Then 20 ℃
P is crystallized and separated as magnesium phosphate Mg ₃ (PO ₄ ) by holding at the following temperature for 2 to 3 hours.

(8) V recovery step V is added to the filtrate after the removal of P from the ammonium metavanadate NH _4.
1.1 to the chemical equivalent required to recover as VO _3.
Add 3 times ammonium chloride NH ₄ Cl and add 20 to 3
The reaction is carried out at 0 ° C. for 0.5 to 1 hour to obtain ammonium vanadate crystals. This is reacted at 400 to 500 ° C. for 0.5 to 1 hour to obtain ammonium metavanadate crystals. This is calcined at 400 to 500 ° C. for another 0.5 to 1 hour to obtain vanadium pentoxide V ₂ O ₅ .

(9) Step of recovering Mo To the filtrate after recovery of V, add hydrochloric acid of 1.1 to 1.3 times the chemical equivalent required to recover Mo as H ₂ Mo ₄ molybdate, and add 30 to 60 ° C. For 2 to 3 hours to obtain molybdic acid.

(10) Impurity removal step-(B) The liquid after the recovery of Mo contains a trace amount of components, and is neutralized to pH 8.5 with calcium hydroxide, and then separated by filtration. Get.

According to the present invention, the process described above
An object of the present invention is to provide a method for recovering valuable metals of Ni, Co, Mo and V from a waste Ni catalyst at a high yield. The following describes examples and exemplifies the above contents.

[0024]

EXAMPLE 1 250 g of Ni waste catalyst having the components shown in Table 1 was mixed with 1,000 ml of water, pulverized to 150 mesh or less by a ball mill, and leached with water at 100 ° C. for 3 hours. The leaching solution, leaching residue and leaching rate as shown were obtained.

[0025]

[Table 1]

[0026]

[Table 2]

Mo and V are 62.1% and 30.4%, respectively.
Has been leached.

[0028]

Example 2 225 g of water leaching residue obtained in Example 1
The, H ₂ SO _4: water -1: Temperature 12 1 of sulfuric acid 572ml
After steaming at 0 ° C. for 1 hour, the product was dissolved in 2,250 ml of water, and as a result, a leachate, a leach residue and a leach rate as shown in Table 3 were obtained. The leaching rates of Ni, Co, Mo and V were 91.6 each.
%, 94.6%, 100.0% and 91.7%.

[0029]

[Table 3]

[0030]

Example 3 The pH of 2,250 ml of the filtrate obtained in Example 2 was adjusted to pH 3.6 with Ca (OH) ₂ , and the filtrate collected by filtration and separation contained NaHS at a ratio of 1% to Ni, CO and Mo. Then, 1 equivalent was added and reacted at 60 ° C. for 1 hour to obtain a mixed sulfide, a filtrate and a recovery rate shown in Table 4. The Ni, Co and Mo components in the mixed sulfide were 3
0.6%, 5.7% and 1.2%. At this time, the recovery rates of Ni, Co and Mo were 99.9%, 99.
3% and 98.8%.

[0031]

[Table 4]

[0032]

Example 4 0.4 g of magnesium chloride was added to 1,000 ml of the water leachate of Example 1, reacted at a temperature of 40 ° C. for 2 hours, and cooled at 15 ° C. for 2 hours to obtain the results shown in Table 5. Was. P was separated to the tr state.

[0033]

[Table 5]

[0034]

Example 5 999 ml of the liquid after P separation obtained in Example 4
1.3 g of ammonium chloride NH ₄ Cl was added to the mixture at 25 ° C.
With ammonium metavanadate 2.8.
g was collected. Table 6 shows the recovery status of V. Ammonium metavanadate was calcined at 500 ° C. to recover 2.2 g of vanadium pentoxide.

[0035]

[Table 6]

[0036]

Example 6 1.1 ml of ConcHCl was added to 999 ml of the liquid after V separation shown in Example 5, and reacted at 40 ° C. for 2 hours to recover 0.4 g of molybdic acid. Table 7 shows M
This shows the recovery status of o. Mo was almost completely recovered as molybdic acid.

[0037]

[Table 7]

[0038]

According to the present invention, wet pulverization from Ni waste catalyst is carried out.
Ni, Co, Mo by water leaching and steaming
As mixed sulfide, and Mo and V as molybdic acid and vanadium pentoxide at high yield.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of the recovery method of the present invention.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ Identification code FI C01G 51/00 C01G 51/00 Z 53/00 53/00 B C22B 3/04 C22B 7/00 B 3/44 23/00 101 7/00 34/22 23/00 34/34 101 3/00 A 34/22 Q 34/34 23/04 (72) Inventor Ryuzo Wakamatsu Hachinohe City, Aomori Prefecture (58) Field surveyed (Int.Cl. ⁷ , DB name) B01J 21/00-38/74 C01G 25/00-47/00 C01G 49/10-57/00 C22B 1 / 00-61/00

Claims (1)

(57) [Claims] 1. A Ni waste catalyst and water are mixed and wet pulverized.
Sulfuric acid was added to the leaching residue obtained by water leaching, and the mixture was steamed. After adjusting the pH of the resulting solution, a sulphating agent was added thereto, and Ni,
A method for recovering valuable metals from a waste Ni catalyst, comprising recovering Co and Mo as mixed sulfide.