CN115353187B

CN115353187B - Ce doped pyrite FeS 2 Environment purifying material for treating V and Cr (VI) pollution

Info

Publication number: CN115353187B
Application number: CN202210996393.0A
Authority: CN
Inventors: 李峻峰; 林雨听; 陈愫英; 舒雨玫; 周皓东; 唐柳群; 黄艺; 张佩聪; 余大明
Original assignee: Chengdu Univeristy of Technology
Current assignee: Chengdu Univeristy of Technology
Priority date: 2022-08-19
Filing date: 2022-08-19
Publication date: 2023-05-12
Anticipated expiration: 2042-08-19
Also published as: CN115353187A

Abstract

The invention provides Ce-doped pyrite FeS ₂ An environment purifying material for treating V and Cr (VI) pollution, which belongs to the field of environment purifying materials. The environment purification material of the invention is a certain amount of Ce doped pyrite FeS ₂ Has the capability of cooperatively treating V and Cr (VI) pollution through adsorption and redox. The material is synthesized by taking ferrous sulfate, cerium nitrate, thiourea and sulfur powder as raw materials and obtaining Ce-doped pyrite under the hydrothermal condition of 160-200 ℃. The material can degrade mixed heavy metal pollution of V and Cr (VI) at the same time, has the advantages of simple preparation method, low cost, convenient use and the like, and has good application prospect in the field of heavy metal sewage purification.

Description

Ce doped pyrite FeS 2 Environment purifying material for treating V and Cr (VI) pollution

Technical Field

The invention provides aCe doped pyrite FeS ₂ An environment purifying material for treating V and Cr (VI) pollution, which belongs to the field of environment purifying materials.

Background

With the continuous development of industries such as mine development and metallurgy smelting, the problem of heavy metal pollution is increasingly emphasized. Development of metal minerals containing vanadium, chromium and the like can generate a large amount of tailings, slag and other wastes, and a large amount of accumulated wastes can migrate into a water environment through flushing of rainwater to cause serious water body pollution. How to solve the problem of environmental heavy metal pollution by using an efficient and energy-saving mode becomes a product development hot spot in recent years. Vanadium metal V is a trace element necessary for organisms, however, high concentration of V can affect the growth of organisms and cause diseases and even death of organisms; the heavy metal Cr (VI) has high toxicity, high fluidity, carcinogenicity and distortion, and is heavy metal pollution with high toxicity. Taking a slag field of Panzhihua vanadium titanomagnetite as an example, chromium elements are often associated in vanadium slag, so that sewage near the slag field often contains two heavy metals of V and Cr (VI) at the same time, a complex system for polluting an aqueous phase by composite heavy metals is required, and the treatment means and cost are greatly increased, so that it is necessary to find a material capable of degrading V and Cr (VI) at the same time.

For the coexisting sewage of heavy metals V and Cr (VI), an ion exchange adsorption method and a precipitation method are mainly used for treatment at present, (1) the ion exchange method mainly adsorbs vanadium and chromium ions in a solution through ion exchange resin, then purer vanadium and chromium blend liquid is obtained through analysis, vanadium precipitation is carried out on the blend liquid through ammonium salt or calcium alkali, and chromates are obtained through modes of alkali adjustment, barium salt addition, heating recrystallization and the like. For example, patent CN104556522a adopts ion exchange resin to treat sewage in which vanadium and chromium coexist, and after resolving in alkaline solution, vanadium and chromium are precipitated and crystallized, so that the treatment and recovery of vanadium and chromium can be realized; the patent CN104628087A adopts ion exchange fiber to treat sewage with coexisting vanadium and chromium, then uses calcium salt to precipitate vanadium, and uses sodium hydroxide and barium salt to precipitate chromium. However, the ion exchange method still has a plurality of problems, such as the defects of slower resin treatment rate, harsh resin use condition, large drug addition amount, large process control difficulty, higher treatment cost, easy secondary pollution and the like. (2) The precipitation method mainly comprises the steps of firstly reducing vanadium and chromium elements to move to a new lower low valence state, then adding alkali to precipitate vanadium and chromium simultaneously, for example, patent CN102531221A adopts reducing agents such as sodium metabisulfite, sodium bisulphite and the like to reduce pentavalent vanadium and hexavalent chromium to trivalent, and then adding alkali liquor to the reduced solution to precipitate the vanadium and chromium in the lower valence state. The precipitation method has the defects of large consumption of the required reducing agent and alkali, long reaction treatment time, high process control difficulty, high treatment cost and the like. The existing treatment methods for V and Cr (VI) coexisting sewage have the defects of complex treatment process, high treatment cost, easiness in causing secondary pollution and the like, and in order to meet the actual treatment of V and Cr (VI) coexisting sewage, the development of materials capable of efficiently degrading V and Cr (VI), simple treatment process, low treatment cost and no secondary pollution is urgently needed at present.

Fe contained in ferrous disulfide component ²⁺ And S is ₂ ^2- Can reduce Cr (VI), such as the degradation of natural pyrite to Cr (VI) is studied in the patent CN1245781A, and the pyrite ferrous disulfide and biochar composite material prepared in the patent CN112897624A is used for removing Cr (VI) in the water phase, but the degradation rate of Cr (VI) treated by the materials is lower, the degradation speed is lower, and the actual requirement is difficult to meet; but at present there is no FeS ₂ Relevant reports for V adsorption degradation. To increase pyrite type FeS ₂ The material has the treatment effect on Cr (VI) and V, and the invention dopes Ce into pyrite type FeS ₂ In the method, the oxidation-reduction potential and the surface nuclear power characteristics of the material are changed by doping Ce, so that the reactivity is improved, and the pyrite type FeS with the suitable Ce doping proportion is prepared ₂ The material can cooperatively treat the mixed pollution of Cr (VI) and V, and can play a larger role in environmental purification in the mixed solution of Cr (VI) and V.

Disclosure of Invention

In order to realize the common degradation of heavy metals V and Cr (VI) in sewage, the invention provides Ce-doped pyrite FeS ₂ And (3) treating the environment purifying material polluted by V and Cr (VI).

In order to achieve the above purpose, the present invention adopts the following technical scheme:

step 1, weighing 0.2475-0.25mol of ferrous sulfate and 0.0025-0.0125mol of cerium nitrate, placing the mixture in 400ml of ethanol solution, stirring for 30 minutes, adding 1mol of thiourea and 0.1-0.4 mol of sulfur powder, and stirring for 5-30 minutes at normal temperature to obtain mixed suspension;

and 2, transferring the mixed suspension in the step 1 into a 1000ml solvent thermal reaction kettle, performing solvent thermal reaction for 24-72 hours at a high temperature of 160-200 ℃, taking out, cooling to room temperature, performing solid-liquid separation, cleaning with 300ml ethanol for 3 times, cleaning with 300ml ultrapure water for 3 times, drying at 50-60 ℃ for 6 hours, and grinding to be smaller than 200 meshes.

The invention has the following advantages and beneficial effects: in 40mg/L of V-contaminated liquid, the material can degrade 88.1% of V within 10 minutes; in 40mg/L of Cr (VI) pollution solution, the material can degrade 90.3% of Cr (VI) within 10 minutes; in a mixed pollution solution of V and Cr (VI) of 40mg/L, the material can degrade 99.6 percent of V and 99.0 percent of Cr (VI) within 10 minutes. Compared with other pollution treatment materials which only have degradation effect on one pollutant, the material can realize rapid synergistic degradation of V and Cr (VI), can exert better environmental purification effect in V and Cr (VI) coexisting pollutant liquid, and has the advantages of simple preparation method, high environmental purification efficiency, simple treatment process, low treatment cost, no secondary pollution and the like.

Description of the drawings:

FIG. 1 is a 4% Ce doped pyrite FeS made in accordance with the present invention ₂ XRD spectrum of the material.

FIG. 2 is a 4% Ce doped pyrite FeS made in accordance with the present invention ₂ SEM image of the material.

FIG. 3 is a 4% Ce doped pyrite FeS made in accordance with the present invention ₂ The degradation rate of the material on V and Cr (VI) in mixed pollution liquid of V and Cr (VI) of 40mg/L is shown.

FIG. 4 is a 4% Ce doped pyrite FeS made in accordance with the present invention ₂ Material and pure pyrite FeS ₂ The degradation rate of the material on V and Cr (VI) after the mixed pollution liquid of V and Cr (VI) with the concentration of 40mg/L is reacted for 2 hours is compared with the degradation rate of the material on V and Cr (VI).

The specific embodiment is as follows:

the invention is further illustrated below in connection with the following examples.

Example 1

Ce doped pyrite FeS ₂ And (3) treating the environment purifying material polluted by V and Cr (VI). 0.2475mol of ferrous sulfate and 0.0025mol of cerium nitrate are weighed and placed in 400ml of ethanol, 1mol of thiourea and 0.1mol of sulfur powder are added, and stirring is carried out for 10 minutes at normal temperature; transferring the prepared mixed suspension into a 1000ml solvothermal reaction kettle, solvothermal treating for 24 hours at the temperature of 200 ℃, taking out a sample, washing with ethanol and deionized water for 3 times, drying for 3 hours at the temperature of 60 ℃, and grinding to obtain the sample.

Example 2

Ce doped pyrite FeS ₂ And (3) treating the environment purifying material polluted by V and Cr (VI). Weighing 0.2375mol of ferrous sulfate and 0.0125mol of cerium nitrate, placing in 400ml of ethanol, adding 1mol of thiourea and 0.2mol of sulfur powder, and stirring for 5 minutes at normal temperature; transferring the prepared mixed suspension into a 1000ml solvothermal reaction kettle, solvothermal treating for 72 hours at 180 ℃, taking out a sample, washing with ethanol and deionized water for 3 times, drying for 5 hours at 50 ℃, and grinding to obtain the sample.

Example 3

Ce doped pyrite FeS ₂ And (3) treating the environment purifying material polluted by V and Cr (VI). 0.2425mol of ferrous sulfate and 0.0075mol of cerium nitrate are weighed and placed in 400ml of ethanol, 1mol of thiourea and 0.3mol of sulfur powder are added, and stirring is carried out for 20 minutes at normal temperature; transferring the prepared mixed suspension into a 1000ml solvothermal reaction kettle, solvothermal treating at 200 ℃ for 36 hours, taking out the sample, washing with ethanol and deionized water for 3 times, drying at 50 ℃ for 6 hours, and grinding to obtain the sample.

Example 4

Ce doped pyrite FeS ₂ And (3) treating the environment purifying material polluted by V and Cr (VI). Weighing 0.24mol of ferrous sulfate and 0.01mol of cerium nitrate, placing the mixture in 400ml of ethanol, adding 1mol of thiourea and 0.4mol of sulfur powder, and stirring the mixture for 30 minutes at normal temperature; transferring the prepared mixed suspension into 1000ml of solvothermal solutionAnd in the reaction kettle, taking out the sample after solvothermal treatment at 180 ℃ for 72 hours, cleaning the sample with ethanol and deionized water for 3 times, drying the sample at 60 ℃ for 3 hours, and grinding the sample to obtain the sample.

Taking example 4 as an example, FIG. 1 shows the XRD spectrum of the obtained sample, and can be seen that the XRD spectrum of the obtained sample is well matched with pyrite PDF#42-1340, and no peak corresponding to sulfide or oxide of Ce appears, indicating that the method prepares Ce-doped pyrite FeS ₂ A material; FIG. 2 is an SEM image of the resulting sample, which was prepared as regular spheres of 3-5 μm.

FIG. 3 is Ce doped pyrite FeS ₂ The degradation rate graph (feed ratio is 2 g/L) of the material in the mixed pollution liquid of V and Cr (VI) of 40mg/L to V and Cr (VI) shows that the material can degrade 99.6% of V and 99.0% of Cr (VI) within 10 minutes, and the material can play a good role in environmental purification in the coexisting pollution liquid of V and Cr (VI).

FIG. 4 is a graph showing the degradation rate of pure phase pyrite and Ce doped pyrite on V and Cr (VI) in 40mg/L of mixed pollution solution of V and Cr (VI) (reaction time 2 hours), wherein pure Xiang Huangtie ore can degrade 90.1% of V and 86.1% of Cr (VI) within 2 hours, and Ce doped pyrite can degrade 99.6% of V and 99.0% of Cr (VI) within 2 hours. Experiments show that the pyrite doped with Ce can treat V and Cr (VI) coexisting pollutant liquid more effectively

The foregoing description is only illustrative of the present invention and is not intended to limit the scope of the invention, and all equivalent changes in the content of the description and drawings, or direct or indirect application in other related technical fields, are included in the scope of the invention.

Claims

1. Ce doped pyrite FeS ₂ An environmental purification material for treating V and Cr (VI) pollution, wherein the material is characterized by comprising the following components: pyrite phase FeS doped with Ce accounting for 1-5% of total metal ions ₂ 。

2. A Ce-doped pyrite FeS as described in claim 1 ₂ Environmental purification material for treating V and Cr (VI) pollution, the morphological characteristics of the material are 3-5 mu m microsphere FeS ₂ 。

3. A Ce-doped pyrite FeS as described in claim 1 ₂ The environment purifying material for treating V and Cr (VI) pollution has the functions of reducing and degrading Cr (VI) and adsorbing and degrading V, and can realize the synergistic degradation of V and Cr (VI), and the material can degrade 99.6% of V and 99.0% of Cr (VI) in 10 min.