Preparation method and application of iron-manganese-titanium composite metal adsorbent for removing thallium

Abstract

The invention provides a preparation method and application of an iron-manganese-titanium composite metal adsorbent for removing thallium, and relates to the technical field of preparation of composite metal adsorbents. The preparation method of the adsorbent comprises the following steps: firstly, dissolving manganese chloride, ferrous sulfate heptahydrate and titanium sulfate in water, slowly dropwise adding a sodium hydroxide solution serving as a precipitator into a mixed liquid of the three solutions, carrying out suction filtration separation and drying on the liquid and the solid, fully grinding to obtain primary powder, and calcining the primary powder in a Markov furnace to obtain secondary powder; and grinding and sieving through a mesh sieve to obtain the iron-manganese-titanium composite metal adsorbent. The adsorbent has high adsorption capacity, good selectivity and excellent regeneration performance, can effectively remove the thallium element in a water body, and is one of effective ways for removing the thallium element in the water body.

Description

Technical Field

[0001] The invention relates to the technical field of composite metal adsorbent preparation, in particular to a preparation method and application of an iron-manganese-titanium composite metal adsorbent for removing thallium. Background Art

[0002] Thallium is a toxic heavy metal element, which is widely present in industrial wastewater and poses a serious threat to the environment and human health. At present, the methods used to remove Tl(I) from water include adsorption, redox precipitation, solvent extraction, biological purification, chemical coagulation, ion exchange and adsorption. Among them, adsorption has attracted wide attention due to its simple operation, low cost and significant effect. However, existing adsorption materials often have problems such as low adsorption capacity, poor selectivity and difficulty in regeneration. Summary of the invention

[0003] In order to solve the above technical problems existing in the prior art, the embodiment of the present invention provides a preparation method and application of an iron-manganese-titanium composite metal adsorbent for removing thallium. The technical solution is as follows:

[0004] A method for preparing an iron-manganese-titanium composite metal adsorbent for removing thallium comprises the following steps:

[0005] S1, dissolving manganese chloride, ferrous sulfate heptahydrate, and titanium sulfate in water at room temperature in proportion, and then mixing the solutions to prepare a mixed solution;

[0006] S2, adding the sodium hydroxide solution dropwise into the mixed solution prepared in step S1, stirring with a magnetic stirrer, and then separating the liquid and solid by suction filtration;

[0007] S3, the solid obtained by suction filtration was placed in a blast drying oven for drying, taken out and put into a mortar for full grinding, and then passed through a 100 mesh sieve to obtain a primary powder;

[0008] S4. The primary powder is placed in a Marsh furnace for calcination, and then further ground and sieved to obtain an iron-manganese-titanium composite metal adsorbent.

[0009] In the step S1, the molar ratio of manganese chloride: ferrous sulfate heptahydrate: titanium sulfate is 1-1.05: 3-3.05: 3-3.05.

[0010] In the mixed solution in step S1, the concentration of manganese chloride is 0.33-0.34 mol / L, the concentration of ferrous sulfate heptahydrate is 1-1.02 mol / L, the concentration of titanium sulfate is 1-1.02 mol / L, and the amount of water used is 300-305 ml.

[0011] In step S2, the concentration of the sodium hydroxide solution is 1 mol / L, and the volume ratio of the sodium hydroxide solution to the mixed solution is 1:3; the sodium hydroxide solution is added dropwise into the mixed solution at a rate of 1 drop / s; and the speed of the magnetic stirrer is 75 r / min.

[0012] In step S3, the drying temperature is 60-70° C. and the drying time is 20-24 hours.

[0013] The temperature of the Martens furnace in step S4 is 500° C., the heating rate is 10° C. / min, the insulation time is 2-2.5 h, and after grinding, the iron-manganese-titanium composite metal adsorbent is obtained by passing through a 100-mesh sieve.

[0014] The application of the above-mentioned iron-manganese-titanium composite metal adsorbent for removing thallium comprises the following steps:

[0015] (1) Adding the prepared iron-manganese-titanium composite metal adsorbent into a thallium-containing water body with a pH of 7;

[0016] (2) Stir the water and adsorbent using a magnetic stirrer at room temperature for 10 to 60 minutes;

[0017] (3) After the adsorption is completed, the adsorbent that has adsorbed thallium is regenerated.

[0018] In the step (1), the thallium content in the thallium-containing water is 10-11 mg / L, and the amount of adsorbent used is 0.5 g / L.

[0019] The rotation speed of the magnetic stirrer in step (2) is 150 r / min.

[0020] The regeneration treatment in step (3) includes acid washing, alkali washing and heat treatment.

[0021] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0022] In the above method, the prepared adsorbent has high adsorption capacity, good selectivity and excellent regeneration performance, and can effectively remove thallium from water. Through the synergistic effect of the iron-manganese-titanium composite metal, the adsorption capacity and selectivity of the adsorbent for thallium are improved; the preparation method is simple, low-cost, and easy to mass produce; the adsorbent has good regeneration performance and can be reused, reducing the processing cost. After the adsorption, the concentration of thallium is reduced to about 3ppb, which is far lower than the national thallium emission standard. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 The present invention provides a flow chart of a method for preparing and applying an iron-manganese-titanium composite metal adsorbent for removing thallium. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is described below in conjunction with the accompanying drawings.

[0026] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the word "example" is intended to present the concept in a specific way. In addition, in the embodiments of the present invention, the meaning expressed by "and / or" can be both, or it can be either of the two.

[0027] In the embodiments of the present invention, sometimes a subscript such as W1 may be written as a non-subscript such as W1. When the difference is not emphasized, the meanings to be expressed are the same.

[0028] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0029] The embodiment of the present invention provides a preparation method and application of an iron-manganese-titanium composite metal adsorbent for removing thallium. Figure 1 The process flow chart of the preparation and application of the iron-manganese-titanium composite metal adsorbent for removing thallium shown includes the following steps:

[0030] A method for preparing an iron-manganese-titanium composite metal adsorbent for removing thallium comprises the following steps:

[0031] S1, dissolving manganese chloride, ferrous sulfate heptahydrate, and titanium sulfate in water at room temperature in proportion, and then mixing the solutions to prepare a mixed solution;

[0032] S2, adding the sodium hydroxide solution dropwise into the mixed solution prepared in step S1, stirring with a magnetic stirrer, and then separating the liquid and solid by suction filtration;

[0033] S3, the solid obtained by suction filtration was placed in a blast drying oven for drying, taken out and put into a mortar for full grinding, and then passed through a 100 mesh sieve to obtain a primary powder;

[0034] S4. The primary powder is placed in a Marsh furnace for calcination, and then further ground and sieved to obtain an iron-manganese-titanium composite metal adsorbent.

[0035] The application of the composite metal adsorbent comprises the following steps:

[0036] (1) Adding the prepared iron-manganese-titanium composite metal adsorbent into a thallium-containing water body with a pH of 7;

[0037] (2) Stir the water and adsorbent using a magnetic stirrer at room temperature for 10 to 60 minutes;

[0038] (3) After the adsorption is completed, the adsorbent that has adsorbed thallium is regenerated.

[0039] This will be described below with reference to specific embodiments.

[0040] Example 1

[0041] according to Figure 1 In the process shown, in a molar ratio of manganese chloride (Mn): ferrous sulfate heptahydrate (Fe): titanium sulfate (Ti) = 1:3:3, they are dissolved in water and added to a beaker for mixing, and stirred with a magnetic stirrer at a rate of 75 r / min, and then 100 ml of 1 mol / L sodium hydroxide solution is slowly added to the mixed solution at a rate of 1 drop / s.

[0042] After the dropwise addition was completed, the liquid and solid were separated by suction filtration, and the obtained solid was placed in a blower dryer and dried at 70° C. for 24 h. The solid was taken out and ground to obtain a primary powder.

[0043] The primary powder was placed in a Marsh furnace, heated at 500°C for 2 h at a heating rate of 10°C / min, then ground with a mortar and passed through a 100-mesh sieve to obtain an adsorbent.

[0044] 100 ml of thallium solution with a concentration of 10 mg / L was prepared, the amount of adsorbent added was 0.5 g / L, the pH was adjusted to 7, the speed of the magnetic stirrer was 150 r / min, the solution was taken out at 10 min, 20 min, 30 min, 40 min, and 60 min, and the taken out solution was filtered with a 0.45 water filter head with a diameter of 13 mm, and then the thallium content in the solution was detected by ICP-ms, and the obtained liquid thallium concentration was 1 ppb to 3 ppb.

[0045] Obviously, the prepared composite metal adsorbent achieves effective adsorption and removal of thallium.

[0046] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for preparing an iron-manganese-titanium composite metal adsorbent for removing thallium, characterized in that: The steps include: S1, dissolving manganese chloride, ferrous sulfate heptahydrate, and titanium sulfate in water at room temperature in proportion, and then mixing the solutions to prepare a mixed solution; S2, adding the sodium hydroxide solution dropwise into the mixed solution prepared in step S1, stirring with a magnetic stirrer, and then separating the liquid and solid by suction filtration; S3, the solid obtained by suction filtration was placed in a blast drying oven for drying, taken out and put into a mortar for full grinding, and then passed through a 100 mesh sieve to obtain a primary powder; S4. The primary powder is placed in a Marsh furnace for calcination, and then further ground and sieved to obtain an iron-manganese-titanium composite metal adsorbent.

2. The method for preparing the iron-manganese-titanium composite metal adsorbent for removing thallium according to claim 1, characterized in that: In the step S1, the molar ratio of manganese chloride: ferrous sulfate heptahydrate: titanium sulfate is 1-1.05: 3-3.05: 3-3.

05.

3. The method for preparing the iron-manganese-titanium composite metal adsorbent for removing thallium according to claim 1, characterized in that: In the mixed solution in step S1, the concentration of manganese chloride is 0.33-0.34 mol / L, the concentration of ferrous sulfate heptahydrate is 1-1.02 mol / L, the concentration of titanium sulfate is 1-1.02 mol / L, and the amount of water used is 300-305 ml.

4. The method for preparing the iron-manganese-titanium composite metal adsorbent for removing thallium according to claim 1, characterized in that: In step S2, the concentration of the sodium hydroxide solution is 1 mol / L, and the volume ratio of the sodium hydroxide solution to the mixed solution is 1:3; the sodium hydroxide solution is added dropwise into the mixed solution at a rate of 1 drop / s; and the speed of the magnetic stirrer is 75 r / min.

5. The method for preparing the iron-manganese-titanium composite metal adsorbent for removing thallium according to claim 1, characterized in that: In step S3, the drying temperature is 60-70° C. and the drying time is 20-24 hours.

6. The method for preparing the iron-manganese-titanium composite metal adsorbent for removing thallium according to claim 1, characterized in that: The temperature of the Martens furnace in step S4 is 500° C., the heating rate is 10° C. / min, the insulation time is 2-2.5 h, and after grinding, the iron-manganese-titanium composite metal adsorbent is obtained by passing through a 100-mesh sieve.

7. The use of the iron-manganese-titanium composite metal adsorbent for removing thallium according to claim 1, characterized in that: The steps include: (1) Adding the prepared iron-manganese-titanium composite metal adsorbent into a thallium-containing water body with a pH of 7; (2) Stir the water and adsorbent using a magnetic stirrer at room temperature for 10 to 60 minutes; (3) After the adsorption is completed, the adsorbent that has adsorbed thallium is regenerated.

8. The use of the iron-manganese-titanium composite metal adsorbent for removing thallium according to claim 7, characterized in that: In the step (1), the thallium content in the thallium-containing water is 10-11 mg / L, and the amount of adsorbent used is 0.5 g / L.

9. The use of the iron-manganese-titanium composite metal adsorbent for removing thallium according to claim 7, characterized in that: The rotation speed of the magnetic stirrer in step (2) is 150 r / min.

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