CN114684793A - Method for preparing elemental sulfur from titanium gypsum, titanium white waste acid and yellow phosphorus tail gas - Google Patents
Method for preparing elemental sulfur from titanium gypsum, titanium white waste acid and yellow phosphorus tail gas Download PDFInfo
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- CN114684793A CN114684793A CN202210555646.0A CN202210555646A CN114684793A CN 114684793 A CN114684793 A CN 114684793A CN 202210555646 A CN202210555646 A CN 202210555646A CN 114684793 A CN114684793 A CN 114684793A
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- elemental sulfur
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B17/00—Sulfur; Compounds thereof
- C01B17/02—Preparation of sulfur; Purification
- C01B17/04—Preparation of sulfur; Purification from gaseous sulfur compounds including gaseous sulfides
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B17/00—Sulfur; Compounds thereof
- C01B17/16—Hydrogen sulfides
- C01B17/165—Preparation from sulfides, oxysulfides or polysulfides
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- Removal Of Specific Substances (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
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Abstract
The invention discloses a method for preparing elemental sulfur from titanium gypsum, titanium white waste acid and yellow phosphorus tail gas. The method for preparing the elemental sulfur comprises the following steps: reacting titanium gypsum with CO purified by yellow phosphorus tail gas to generate calcium sulfide; the generated calcium sulfide reacts with the waste sulfuric acid to generate hydrogen sulfide gas; the generated hydrogen sulfide gas is treated by Fe in alkaline solution3+The complex of (a) is oxidized to form elemental sulfur. The method for preparing the elemental sulfur adopts the sulfur source CaSO contained in the titanium gypsum as the sulfur source4The acid source is titanium white sulfuric acid wastewater, and the carbon source is CO contained in yellow phosphorus tail gas. The iron complexing agent can react with air for regeneration. The reaction principle is simple, and the raw material is three wastes, 4Fe3+Ln can be recycled. The method has low cost and strong operability of the process flow, not only solves the problem of the cost of processing by-products in industry and reduces environmental pollution, but also can create certain economic value.
Description
Technical Field
The invention relates to the technical field of chemical industry, in particular to a method for preparing elemental sulfur from titanium gypsum, titanium white waste acid and yellow phosphorus tail gas.
Background
Titanium gypsum is an industrial byproduct generated in the production process of titanium dioxide, the production method of titanium dioxide mainly comprises a sulfuric acid method and a chlorination method, and more than 90% of titanium dioxide enterprises in China adopt the sulfuric acid method for production due to the reasons of technology, process and the like. At present, lime or carbide slag is basically adopted in the production process of titanium dioxide to neutralize a large amount of acidic wastewater generated in the production process, and a large amount of titanium gypsum mainly comprising calcium sulfate dihydrate is generated. The titanium gypsum can be used as retarder or excitant in cement and concrete, and the research uses the titanium gypsum as cementing material, develops light wall material by using the titanium gypsum, produces roadbed material by using the titanium gypsum, and can also be used for producing titanium pigment.
The yellow phosphorus tail gas is a byproduct of yellow phosphorus production, an electric furnace method is usually adopted for the yellow phosphorus production, and the byproduct tail gas is 2500-3000 m for every 1t of yellow phosphorus production3. The main component of the yellow phosphorus tail gas is CO, the content of the CO is generally 85-95%, and the composition of the yellow phosphorus tail gas is changed along with the difference of the composition of raw materials and production operation. At present, except that a few yellow phosphorus manufacturers in China use deeply purified tail gas as high-quality chemical raw materials or fuel and part of tail gas of enterprises as primary fuel gas for drying raw materials, most manufacturers, especially small and medium-sized enterprises, are not fully utilized, 80 percent of the tail gas is combusted by a torch and discharged into the atmosphere, the unpurified yellow phosphorus tail gas contains harmful gases such as sulfur, phosphorus, fluorine, arsenic and the like, the environment is polluted by direct discharge, and CO generated by exhausting and combusting is exhausted2But also results in a "greenhouse effect". Average production of 2750m yellow phosphorus per 1t of produced3The annual emission of the yellow phosphorus electric furnace tail gas in 2011 of China is 28 hundred million m3。
Disclosure of Invention
In order to solve the problem of the existing industrial byproduct treatment, the invention uses titanium gypsum, waste sulfuric acid and yellow phosphorus tail gas as raw materials to realize the method for preparing elemental sulfur from calcium sulfate in the titanium gypsum, sulfuric acid in titanium white sulfuric acid waste water and CO in the yellow phosphorus tail gas.
The method for preparing the elemental sulfur comprises the following steps:
reacting titanium gypsum with CO purified by yellow phosphorus tail gas to generate calcium sulfide; the generated calcium sulfide reacts with the waste sulfuric acid to generate hydrogen sulfide gas; the generated hydrogen sulfide gas is treated by Fe in alkaline solution3+The complex of (a) is oxidized to form elemental sulfur.
Preferably, the CO purified by the titanium gypsum and the yellow phosphorus tail gas is heated to 800-1000 ℃ at the heating rate of 2-20 ℃/min and reacts for 1.5-4.5 h.
Further preferably, the CO purified by the titanium gypsum and the yellow phosphorus tail gas is heated to 820-950 ℃ at the heating rate of 5 ℃/min for reaction for 2 h.
Preferably, the waste sulfuric acid is titanium white sulfuric acid wastewater.
Preferably, the mass ratio of the generated calcium sulfide to the titanium white sulfuric acid wastewater is 1 (4-5).
Preferably, the alkaline solution is an aqueous solution containing the following components in percentage by mass: 4.0 percent of trisodium citrate, 4.0 percent of ferric nitrate, 0.4mol/L of sodium carbonate and 0.4mol/L of sodium bicarbonate.
Preferably, the Fe3+The complex of (A) is 16Fe3+Ln。
Preferably, the hydrogen sulfide gas generated is replaced by Fe in an alkaline solution3+The complex is oxidized for 1 to 1.5 hours.
Preferably, the titanium gypsum is put into a quartz boat, the quartz boat is put into a tube furnace, and CO purified by yellow phosphorus tail gas is introduced.
Preference is given toIntroducing air into the alkaline solution, and introducing the reacted Fe2+Is oxidized to Fe3+Complex of (2), Fe2+The ratio of the amount of the substance of the complex to the amount of the substance of oxygen in the air is 1: 1.2.
Fe3+Is reduced to Fe2+The complex can be oxidized into Fe in the presence of air or hydrogen peroxide3+The complex can be recycled. Green and environment-friendly, and reduces the production cost.
The method for preparing the elemental sulfur provided by the invention has the advantages that the raw materials are industrial byproducts, the raw materials are low in price, the operability is strong, the principle is simple, the equipment is simple, the production cost is low, and certain economic benefits are achieved.
Compared with the prior art, the invention has the following beneficial effects:
(1) the method for preparing the elemental sulfur provided by the invention utilizes titanium gypsum (CaSO)4) Titanium white sulfuric acid wastewater (H)2SO4) And the yellow phosphorus tail gas (CO) is used as a raw material to react, so that the pollution to the earth surface, water, soil and air is reduced. The invention provides a comprehensive resource utilization method of titanium gypsum, titanium white sulfuric acid wastewater and yellow phosphorus tail gas.
(2) The method for preparing the elemental sulfur adopts the sulfur source CaSO contained in the titanium gypsum as the sulfur source4The acid source is titanium white sulfuric acid wastewater, and the carbon source is CO contained in yellow phosphorus tail gas. The iron complexing agent can react with air for regeneration. The reaction principle is simple, and the raw material is three wastes, 4Fe3+Ln can be recycled. The method has low cost and strong operability of the process flow, not only solves the problem of the cost of processing by-products in industry and reduces environmental pollution, but also can create certain economic value.
Detailed Description
The method for preparing the elemental sulfur provided by the invention comprises the following steps: weighing a certain amount of titanium gypsum, placing into a quartz boat, placing the quartz boat into a tube furnace, introducing CO purified by yellow phosphorus tail gas, and heating at 5 deg.C for min-1Reacting for 2 hours at 800-1000 ℃ to generate calcium sulfide. The titanium white sulfuric acid waste water reacts with the generated calcium sulfide to generate hydrogen sulfide gas, and the hydrogen sulfide gasGas and Fe3+Ln (alkaline solution) is oxidized in liquid phase for 1h to 1.5h to generate elemental sulfur, and air is introduced to oxidize Fe2+Oxidation of Ln to 4Fe3+Ln is recycled in the test process.
The preparation method relates to the following equation:
(1)CaSO4+4CO→CaS+4CO2↑
(2)CaS+H2SO4→CaSO4+H2S↑
(3)8H2S+16Fe3+Ln→16Fe2+Ln+S8+16H+
(4)4Fe2+Ln+O2+2H2O→4Fe3+Ln+4OH-
example 1 preparation of elemental sulfur from titanium Gypsum, spent sulfuric acid and yellow phosphorus Tail gas
1g of titanium gypsum (CaSO) was weighed4.2H2O) putting the quartz boat (purchased from crystaline quartz), putting the quartz boat into a tube furnace (purchased from Nanjing Bo-Tong instrument, Inc., model: TL1200 tube furnace), introducing CO purified by yellow phosphorus tail gas, and calculating according to the amount of calcium sulfate contained in the titanium gypsum, for example, titanium gypsum containing 50% of calcium sulfate by mass fraction, wherein 95CO is required to be introduced for 1kg of titanium gypsum; heating to 820 deg.C/min at a heating rate of 5 deg.C/min, reacting for 2 hr, and cooling to room temperature to obtain calcium sulfide (CaS). The obtained CaS and titanium dioxide sulfuric acid wastewater (H) are utilized2SO4) Reacting 1kg of GaS and 4kg of titanium white sulfuric acid wastewater at normal temperature and pressure to generate H2S gas, H to be generated2Introducing S gas into a container containing alkaline solution through a corresponding pipeline to ensure that H is generated2S gas is Fe-coated in alkaline solution3+Complex of 16Fe3+Ln is subjected to hydrogen sulfide desulfurization treatment and reacts for 1 hour to be oxidized into elemental sulfur. The alkaline solution comprises the following components in percentage by mass: 4.0 percent of trisodium citrate, 4.0 percent of ferric nitrate, 0.4mol/L of sodium carbonate and 0.4mol/L of sodium bicarbonate.
Introducing air to lead Fe2+Oxidation of Ln to 4Fe3+Ln is recycled in the test process. Introducing air into the alkaline solution, wherein the specific amount is complexed according to FeThe amount of the substance is converted. The ratio of the amount of substance of iron complexing agent to the amount of substance of oxygen in the air was 1: 1.2.
Example 2 preparation of elemental sulfur from titanium Gypsum, spent sulfuric acid and yellow phosphorus Tail gas
1g of titanium gypsum (CaSO) was weighed4.2H2O) is put into a quartz boat (purchased from crystaline quartz), then the quartz boat is put into a tube furnace (purchased from Nanjing Bo-Temmin apparatus, Inc., model: TL1200 tube furnace), CO purified by yellow phosphorus tail gas is introduced, calculation is carried out according to the amount of calcium sulfate contained in titanium gypsum, for example, 100L CO is required to be introduced into 1kg of titanium gypsum, the temperature rise rate is 2 ℃/min, the temperature is raised to 1000 ℃, the heat preservation reaction is carried out for 4.5h, and the calcium sulfide (CaS) is obtained after cooling to room temperature. The obtained CaS and titanium dioxide sulfuric acid wastewater (H) are utilized2SO4) Reacting 1kg of GaS and 5kg of titanium white sulfuric acid wastewater at normal temperature and normal pressure to generate H2S gas, H to be generated2Introducing S gas into a container containing alkaline solution through a corresponding pipeline to ensure that H is generated2S gas is Fe-coated in alkaline solution3+Complex of 16Fe3+Ln is subjected to hydrogen sulfide desulfurization treatment and reacts for 1.5 hours to be oxidized into elemental sulfur. The alkaline solution comprises the following components in percentage by mass: 4.0% of trisodium citrate, 4.0% of ferric nitrate, 0.4mol/L of sodium carbonate and 0.4mol/L of sodium bicarbonate.
Introducing air to lead Fe2+Oxidation of Ln to 4Fe3+Ln is recycled in the test process. And (3) introducing air into the alkaline solution, wherein the specific amount is converted according to the amount of the Fe complex. The ratio of the amount of substance of iron complexing agent to the amount of substance of oxygen in the air was 1: 1.2.
Example 3 preparation of elemental Sulfur Using Titania Gypsum, spent sulfuric acid, and yellow phosphorus Tail gas
1g of titanium gypsum (CaSO) was weighed4.2H2O) is put into a quartz boat (purchased from crystaline quartz), then the quartz boat is put into a tube furnace (purchased from Nanjing Bo-Tong instrument Co., Ltd., model: TL1200 tube furnace), CO purified by yellow phosphorus tail gas is introduced, the calculation is carried out according to the amount of calcium sulfate contained in titanium gypsum, for example, titanium gypsum containing 50 percent of calcium sulfate mass fraction, 10 needs to be introduced for 1kg of titanium gypsum0L of CO, the heating rate is 20 ℃/min, the temperature is raised to 950 ℃, the reaction is carried out for 1.5 hours under the condition of heat preservation, and the calcium sulfide (CaS) is obtained after the reaction is cooled to the room temperature. The obtained CaS and titanium dioxide sulfuric acid wastewater (H) are utilized2SO4) Reacting 1kg of GaS and 5kg of titanium white sulfuric acid wastewater at normal temperature and normal pressure to generate H2S gas, H to be generated2Introducing S gas into a container containing alkaline solution through a corresponding pipeline to ensure that H is generated2S gas is Fe-coated in alkaline solution3+Complex of 16Fe3+Ln is subjected to hydrogen sulfide desulfurization treatment and reacts for 1.5 hours to be oxidized into elemental sulfur. The alkaline solution comprises the following components in percentage by mass: 4.0 percent of trisodium citrate, 4.0 percent of ferric nitrate, 0.4mol/L of sodium carbonate and 0.4mol/L of sodium bicarbonate.
Introducing air to lead Fe2+Oxidation of Ln to 4Fe3+Ln is recycled in the test process. And (3) introducing air into the alkaline solution, wherein the specific amount is converted according to the amount of the Fe complex. The ratio of the amount of substance of iron complexing agent to the amount of substance of oxygen in the air was 1: 1.2.
The above-described embodiments should not be construed as limiting the scope of the invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions can occur, depending on design requirements and other factors. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A method for preparing elemental sulfur from titanium gypsum, titanium white waste acid and yellow phosphorus tail gas comprises the following steps:
reacting titanium gypsum with CO purified by yellow phosphorus tail gas to generate calcium sulfide; the generated calcium sulfide reacts with the waste sulfuric acid to generate hydrogen sulfide gas; the generated hydrogen sulfide gas is treated by Fe in alkaline solution3+The complex of (a) is oxidized to form elemental sulfur.
2. The method for producing elemental sulfur according to claim 1, characterized in that: and the CO purified by the titanium gypsum and the yellow phosphorus tail gas is heated to 800-1000 ℃ at the heating rate of 2-20 ℃/min and reacts for 1.5-4.5 h.
3. The method of claim 2, wherein the elemental sulfur is selected from the group consisting of: and (3) raising the temperature to 820-950 ℃ at the temperature raising rate of 5 ℃/min for reacting for 2 h.
4. The method for producing elemental sulfur according to claim 1, characterized in that: the waste sulfuric acid is titanium white sulfuric acid wastewater.
5. The method for producing elemental sulfur according to claim 1, characterized in that: the mass ratio of the generated calcium sulfide to the titanium white sulfuric acid wastewater is 1 (4-5).
6. The method for producing elemental sulfur according to claim 1, characterized in that: the alkaline solution is an aqueous solution containing the following components in percentage by mass: 4.0 percent of trisodium citrate, 4.0 percent of ferric nitrate, 0.4mol/L of sodium carbonate and 0.4mol/L of sodium bicarbonate.
7. The method for producing elemental sulfur according to claim 1, characterized in that: said Fe3+The complex of (A) is 16Fe3+Ln。
8. The method of claim 1, wherein the method comprises: the generated hydrogen sulfide gas is treated by Fe in alkaline solution3+The complex is oxidized for 1 to 1.5 hours.
9. The method for producing elemental sulfur according to claim 1, characterized in that: and (3) putting the titanium gypsum into a quartz boat, putting the quartz boat into a tube furnace, and introducing CO purified by yellow phosphorus tail gas.
10. The method of claim 1, wherein the method comprises: introducing air into the alkaline solution, and reacting the Fe2+By complexation ofOxidation of the compound to Fe3+Complex of (2), Fe2+The ratio of the amount of substance of the complex of (a) to the amount of substance of oxygen in the air is 1: 1.2.
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