Method for recycling metal oxide from waste flue gas denitration catalyst

A denitration catalyst and waste flue gas technology, which is applied in the field of non-ferrous metal recovery, can solve the problems such as comprehensive recovery of waste SCR flue gas denitration catalysts that cannot be used, and achieve the effects of rapid recycling, cost reduction and simple process

Active Publication Date: 2010-12-22

HUADIAN ELECTRIC POWER SCI INST CO LTD

6 Cites 146 Cited by

AI-Extracted Technical Summary

Problems solved by technology

However, it should be pointed out that most of the currently retrieved waste catalyst recovery process patents are for hydrodesulfurization catalysts in the petrochemical field. The use of catalysts...

Abstract

The invention discloses a method for recycling a metal oxide from a waste flue gas denitration catalyst, comprising the following steps of: crushing the waste flue gas denitration catalyst to carry out pre-roasting pretreatment at high temperature; adding Na2CO3 into the waste flue gas denitration catalyst according to the proportion, mixing, pulverizing and roasting at high temperature to obtain a sintering block; crushing the sintering block and putting the crushed sintering block into hot water, and stirring and lixiviating to obtain titanate; adding sulphuric acid into the titanate, filtering, water-washing and roasting to obtain TiO2; adding the sulphuric acid into the lixiviated filtering liquid to regulate a pH value to 8.0-9.0; adding excessive NH4Cl for vanadium precipitation; decomposing NH4VO3 obtained from filtering at high temperature to prepare a V2O5 product; adding hydrochloric acid into the filtering liquid subjected to the vanadium precipitation to regulate a pH value to 4.5-5.0; adding CaCl2 for molybdenum and tungsten precipitation; treating the CaM0O4 and CaWO4, obtained from filtering, with the hydrochloric acid and roasting to obtain MoO3 and WO3. The method of the invention has the advantages of simple process and apparatus, high recycling efficiency, good product technical data, large treatment capacity and the like.

Technology Topic

OxideSulfuric acid +7

Image

Examples

Experimental program(5)

Example Embodiment

[0046] Example 1: Such as figure 1 Shown: In this embodiment, the method for recovering metal oxides from waste flue gas denitration catalysts is carried out according to the following steps.

[0047] Raw material pre-roasting: Take the spent honeycomb-type waste flue gas denitration catalyst and put it into the rotary kiln, and perform high-temperature roasting at about 650 ℃ to remove the Hg, As and organic impurities that may be adsorbed on the surface. The temperature is kept constant for 4 hours.

[0048] Mixing and crushing: add Na to the roasted waste flue gas denitration catalyst 2 CO 3 , Na 2 CO 3 And waste flue gas denitration catalyst (according to TiO 2 The molar ratio is 2:1. After being fully mixed by the mixer, it is put into the crusher to be crushed and milled to a particle size ≤200 μm to obtain a mixed powder.

[0049] Sodium roasting: Put the mixed and crushed powder into a rotary kiln for high-temperature roasting at 650-700 ℃, and keep it constant for 4 hours. At high temperatures, the metal oxides in the spent flue gas denitration catalyst can interact with Na 2 CO 3 The reaction generates the corresponding sodium salt, which is finally fired into agglomerates.

[0050] Hot water leaching: The sintered agglomerates after high-temperature roasting are crushed by a crusher, and then leached with hot water at 80~90℃ under sufficient stirring to make the NaVO produced by the reaction 3 , Na 2 WO 4 And Na 2 MoO 4 Dissolved in water. The water consumption is 5:1 liquid-solid weight ratio, and the leaching time is 2 hours. The precipitate is filtered, and finally the precipitated titanate crude product and filtrate are obtained.

[0051] Titanium extraction by precipitation: adding crude titanate to sulfuric acid with a volume concentration of 10%, filtering, washing and roasting to obtain TiO 2 Powder. Finish TiO 2 Of recycling.

[0052] Vanadium extraction by precipitation: add 10% sulfuric acid to the filtrate, adjust the pH to 8.0, and then add NH 4 Cl sinks vanadium, its dosage is (V+W+Mo): NH 4 + =1:2 (molar ratio). After precipitation, filter to get NH 4 VO 3 And the second filtrate, the filtered NH 4 VO 3 Washed, put into the tablet furnace, decomposed at 800~850 ℃ to obtain molten V 2 O 5 , And then made into a sheet is the finished product. Finish V 2 O 5 Of recycling.

[0053] Precipitation to extract molybdenum and tungsten: add 10% hydrochloric acid to the second filtrate to adjust the pH to 5.0, then add CaCl 2 Immersion molybdenum, tungsten, CaCl 2 Dosage is (Mo+W): CaCl 2 =1:2 (molar ratio). The solid filter cake is separated out, the filter cake is treated with 10% hydrochloric acid at 40~50 ℃, and the CaMoO obtained by filtration 4 And CaWO 4 Solid, then acid precipitation and filtration to obtain H 2 MoO 4 And H 2 WO 4 , The prepared H 2 MoO 4 And H 2 WO 4 , MoO can be obtained after roasting 3 With WO 3. Complete MoO 3 With WO 3 Of recycling. Thus, the production process of recovering metal oxides from the waste flue gas denitration catalyst is completed. Effective recovery of TiO 2 , V 2 O 5 , MoO 3 And WO 3.

Example Embodiment

[0054] Example 2: Such as figure 1 Shown: In this embodiment, the method for recovering metal oxides from waste flue gas denitration catalysts is carried out according to the following steps.

[0055] Raw material pre-roasting: Take the spent honeycomb-type waste flue gas denitration catalyst and put it into the rotary kiln, and perform high-temperature roasting at about 650 ℃ to remove the Hg, As and organic impurities that may be adsorbed on the surface. The temperature is kept for 3 hours.

[0056] Mixing and crushing: add Na to the roasted waste flue gas denitration catalyst 2 CO 3 , Na 2 CO 3 And waste flue gas denitration catalyst (according to TiO 2 The molar ratio is 2.5:1. After being fully mixed by the mixer, it is put into the crusher to be crushed and milled to a particle size ≤200 μm to obtain a mixed powder.

[0057] Sodium roasting: Put the mixed and crushed mixed powder into the rotary kiln for high-temperature roasting at 650-700 ℃, and keep it constant for 5 hours. At high temperatures, the metal oxides in the spent flue gas denitration catalyst can interact with Na 2 CO 3 The reaction generates the corresponding sodium salt, which is finally fired into agglomerates.

[0058] Hot water leaching: The sintered agglomerates after high-temperature roasting are crushed by a crusher, and then leached with hot water at 80~90℃ under sufficient stirring to make the NaVO produced by the reaction 3 , Na 2 WO 4 And Na 2 MoO 4 Dissolved in water. The water consumption is 6:1 liquid-solid weight ratio, and the leaching time is 2 hours. The precipitate is filtered, and finally the precipitated titanate crude product and filtrate are obtained.

[0059] Titanium extraction by precipitation: adding crude titanate to sulfuric acid with a volume concentration of 8%, filtering, washing and roasting to obtain TiO 2 Powder. Finish TiO 2 Of recycling.

[0060] Vanadium extraction by precipitation: add 8% sulfuric acid to the filtrate, adjust the pH to 8.5, and then add NH 4 Cl sinks vanadium, its dosage is (V+W+Mo): NH 4 + =1:3 (molar ratio). After precipitation, filter to get NH 4 VO 3 And the second filtrate, the filtered NH 4 VO 3 Washed, put into the tablet furnace, decomposed at 800~850 ℃ to obtain molten V 2 O 5 , And then made into a sheet is the finished product. Finish V 2 O 5 Of recycling.

[0061] Precipitation to extract molybdenum and tungsten: adjust the pH to 4.6 by adding 9% hydrochloric acid to the secondary filtrate, then add CaCl 2 Immersion molybdenum, tungsten, CaCl 2 Dosage is (Mo+W): CaCl 2 =1:2.5 (molar ratio). The solid filter cake is precipitated, and the filter cake is treated with 6% hydrochloric acid at 40~50 ℃, and the CaMoO obtained is filtered 4 And CaWO 4 Solid, then acid precipitation and filtration to obtain H 2 MoO 4 And H 2 WO 4 , The prepared H 2 MoO 4 And H 2 WO 4 , MoO can be obtained after roasting 3 With WO 3. Complete MoO 3 With WO 3 Of recycling. Thus, the production process of recovering metal oxides from the waste flue gas denitration catalyst is completed. Effective recovery of TiO 2 , V 2 O 5 , MoO 3 And WO 3.

Example Embodiment

[0062] Example 3: Such as figure 1 Shown: In this embodiment, the method for recovering metal oxides from waste flue gas denitration catalysts is carried out according to the following steps.

[0063] Raw material pre-roasting: Take the spent honeycomb-type waste flue gas denitration catalyst and put it into the rotary kiln, and perform high-temperature roasting at about 650 ℃ to remove the Hg, As and organic impurities that may be adsorbed on the surface. The temperature is kept for 2 hours.

[0064] Mixing and crushing: add Na to the roasted waste flue gas denitration catalyst 2 CO 3 , Na 2 CO 3 And waste flue gas denitration catalyst (according to TiO 2 The molar ratio is 3:1. After being fully mixed by the mixer, it is put into the crusher to be crushed and milled to a particle size ≤200 μm to obtain a mixed powder.

[0065] Sodiumized roasting: Put the mixed and crushed mixed powder into a rotary kiln for high-temperature roasting at 650-700 ℃, and hold it at a constant temperature for 3 hours. At high temperatures, the metal oxides in the spent flue gas denitration catalyst can interact with Na 2 CO 3 The reaction generates the corresponding sodium salt, which is finally fired into agglomerates.

[0066] Hot water leaching: The sintered agglomerates after high-temperature roasting are crushed by a crusher, and then leached with hot water at 80~90℃ under sufficient stirring to make the NaVO produced by the reaction 3 , Na 2 WO 4 And Na 2 MoO 4 Dissolved in water. The water consumption is a liquid-solid weight ratio of 9:1, and the leaching time is 1 hour. The precipitate is filtered, and finally the precipitated titanate crude product and filtrate are obtained.

[0067] Titanium extraction by precipitation: adding crude titanate to sulfuric acid with a volume concentration of 77%, filtering, washing and roasting to obtain TiO 2 Powder. Finish TiO 2 Of recycling.

[0068] Vanadium extraction by precipitation: add sulfuric acid with a volume concentration of 7% to the filtrate, adjust the pH to 8.5, and then add NH 4 Cl sinks vanadium, its dosage is (V+W+Mo): NH 4 + =1:3.5 (molar ratio). After precipitation, filter to get NH 4 VO 3 And the second filtrate, the filtered NH 4 VO 3 Washed, put into the tablet furnace, decomposed at 800~850 ℃ to obtain molten V 2 O 5 , And then made into a sheet is the finished product. Finish V 2 O 5 Of recycling.

[0069] Precipitation to extract molybdenum and tungsten: add 6% hydrochloric acid to the second filtrate to adjust the pH to 4.5, then add CaCl 2 Immersion molybdenum, tungsten, CaCl 2 Dosage is (Mo+W): CaCl 2 =1:3 (molar ratio). The solid filter cake is separated out, the filter cake is treated with 5% hydrochloric acid at 40~50 ℃, and the CaMoO obtained is filtered 4 And CaWO 4 Solid, then acid precipitation and filtration to obtain H 2 MoO 4 And H 2 WO 4 , The prepared H 2 MoO 4 And H 2 WO 4 , MoO can be obtained after roasting 3 With WO 3. Complete MoO 3 With WO 3 Of recycling. Thus, the production process of recovering metal oxides from the waste flue gas denitration catalyst is completed. Effective recovery of TiO 2 , V 2 O 5 , MoO 3 And WO 3.

PUM

Description & Claims & Application Information

We can also present the details of the Description, Claims and Application information to help users get a comprehensive understanding of the technical details of the patent, such as background art, summary of invention, brief description of drawings, description of embodiments, and other original content. On the other hand, users can also determine the specific scope of protection of the technology through the list of claims; as well as understand the changes in the life cycle of the technology with the presentation of the patent timeline. Login to view more.

Classification and recommendation of technical efficacy words

Strong maneuverability
Simple process

Method for realizing fast and automatic modeling of transformer substation IEC 61850 by adopting XML information recombination

ActiveCN101706773AEasy system maintenanceStrong maneuverability

Owner:BEIJING SIFANG JIBAO AUTOMATION +1

Method for recycling metal oxide from waste flue gas denitration catalyst

AI-Extracted Technical Summary

Problems solved by technology

Abstract

Image

Examples

Example Embodiment

Example Embodiment

Example Embodiment

PUM

Description & Claims & Application Information

Similar technology patents

Image sensor and method of manufacturing the same

Ammonium polyphosphate, montmorillonite nano complex and preparation thereof

Treating method for oily sludge

Method for preparing superhydrophobic coating by adopting supersonic electric arc spaying technique

Chinese medicinal herb-seaweed composite biological agent and preparation method thereof

Classification and recommendation of technical efficacy words

Method for realizing fast and automatic modeling of transformer substation IEC 61850 by adopting XML information recombination

Loach fish fry artificial propagation method

Cathode diachylon used for power-type lead-acid storage battery and manufacture method thereof

Method for cultivating asparaguses in North China

Construction method of bearing frame of corridor structure

Multimedia data recording apparatus, monitor system, and multimedia data recording method

Simultaneously desulfurization and denitration wet ammonia flue gas cleaning technology and system thereof

Method for removing COS from a stream of hydrocarbon fluid and wash liquid for use in a method of this type

Method for preparing graphite alkyne film

Method for recovering valuable metals from waste lithium manganese oxide battery