CN109317089B - Magnetic adsorption material, preparation method thereof and method for treating thallium-containing wastewater by using magnetic adsorption material - Google Patents
Magnetic adsorption material, preparation method thereof and method for treating thallium-containing wastewater by using magnetic adsorption material Download PDFInfo
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- CN109317089B CN109317089B CN201811439179.5A CN201811439179A CN109317089B CN 109317089 B CN109317089 B CN 109317089B CN 201811439179 A CN201811439179 A CN 201811439179A CN 109317089 B CN109317089 B CN 109317089B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
- B01J20/06—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising oxides or hydroxides of metals not provided for in group B01J20/04
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28002—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their physical properties
- B01J20/28009—Magnetic properties
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/28—Treatment of water, waste water, or sewage by sorption
- C02F1/281—Treatment of water, waste water, or sewage by sorption using inorganic sorbents
Abstract
The invention discloses a magnetic adsorption material, a preparation method thereof and a method for treating thallium-containing wastewater. The preparation method comprises dissolving manganese acetate in water, adding citric acid for dissolving and diluting, adding manganese ferrite, mixing, drying, pulverizing, and roasting. The method for treating the thallium-containing wastewater by using the magnetic adsorbing material comprises the following steps: step 1, adding manganese dioxide loaded manganese ferrite into thallium-containing industrial wastewater, and adsorbing thallium in the industrial wastewater by using a magnetic adsorption material; step 2, an external magnetic field attracts the magnetic adsorption material attached with thallium; step 3, performing solid-liquid separation, wherein the supernatant is the treated water from which the thallium element is removed; the method for recovering thallium by using the magnetic adsorption material comprises the following steps: adding nitric acid into the magnetic adsorption material with thallium attached to adjust the pH value, externally adding a magnetic field to attract the desorbed magnetic adsorption material, and performing solid-liquid separation to obtain supernatant, namely the enriched recovery solution concentrated with thallium.
Description
Technical Field
The invention belongs to the technical field of environmental protection, and particularly relates to manganese dioxide (MnO)2) Loaded manganese ferrite (MnFe)2O4) Magnetic adsorption material and preparation and application thereof.
Background
Thallium (Tl) belongs to a rare dispersion element in the earth crust, is often associated with metal sulfide ores such as iron, zinc, copper and the like, and exists in coal fields and petroleum in a form of organic matter combination. Thallium and the compound thereof have high-intensity biological toxicity, the toxicity to mammals is even stronger than that of heavy metals such as lead, mercury and the like, the thallium and the compound thereof are easy to accumulate in organisms, and the excessive exposure of human bodies can cause permanent toxic injury to nervous systems, digestive systems, skins, hairs and the like.
At present, the demand of mineral resources in China is increased, and the exploitation scale of low-temperature ore deposits accompanied by thallium is continuously enlarged, so that the problem of serious thallium pollution is caused. In recent years, more thallium pollution events with larger influence occur in China. In 2010, the Shaoguan smelter illegally discharges thallium-containing wastewater, so that thallium at the middle and upstream river section of Guangdong north river exceeds the standard, and water supply of a plurality of cities is influenced. In 2013, the water body of the Guangxi Hejiang is polluted by cadmium and thallium, and the thallium exceeds the standard by 2.4 times. The problem of thallium pollution of water bodies increasingly draws wide attention. The American Environmental Protection Agency (EPA) stipulates that thallium does not exceed 0.14mg/L in industrial discharged water and thallium does not exceed 2 mug/L in domestic drinking water, while the national thallium pollutant discharge Standard for Industrial wastewater (DB 44/1989-2017) stipulates that the limit value of thallium concentration is 0.005mg/L and the maximum content of thallium is 0.12 mug/L in the sanitary Standard for domestic drinking water.
The prior treatment methods of thallium-containing water bodies and soil comprise a phytoremediation method, an ion exchange method, a chemical precipitation method, a solution extraction method, a microbiological technology method, an adsorption method and the like. The adsorption method is mainly used for treating thallium ions by utilizing the huge specific surface area and abundant surface functional groups of the porous structure material. Compared with other methods, the adsorption method has the advantages of good selectivity, low cost, high efficiency, strong operability and the like, so the adsorption method is the optimal method for treating the thallium-containing wastewater.
However, the existing thallium removal technology for wastewater does not have the functions of thallium element enrichment, concentration and recovery, so that the thallium element removal material becomes a dangerous waste with higher treatment cost. In addition, the existing wastewater thallium removal technology is high in input cost of reagent materials and unstable in thallium removal effect.
Disclosure of Invention
Aiming at the inherent technical defects of the prior thallium removal technology of wastewater, the invention aims to provide a magnetic adsorption material which has high thallium adsorption performance and excellent solid-liquid separation performance, can be recycled, and can realize thallium removal from wastewater and thallium enrichment recovery. The invention also provides a preparation method of the magnetic adsorption material. The invention also provides a method for treating thallium-containing wastewater by using the magnetic adsorbing material.
In order to solve the technical problems:
the invention provides a magnetic adsorption material, which is manganese dioxide loaded with manganese ferrite prepared by a sol-gel method by using manganese acetate as a raw material, manganese ferrite particles as a carrier and citric acid as a complexing agent.
The invention provides a preparation method of the magnetic adsorption material, which comprises the following steps: dissolving manganese acetate in water, adding citric acid for dissolving and diluting, adding manganese ferrite, uniformly mixing, drying, crushing and roasting to obtain manganese dioxide loaded manganese ferrite. In the preparation process, citric acid is used as a complexing agent, citric acid groups are complexed, and manganese ions can be chelated with the citric acid to form a metal chelate contained in a gel network; upon heating, manganese citrate forms manganese dioxide.
The invention provides a method for treating thallium-containing wastewater by using the magnetic adsorbing material, which comprises the following steps:
step 1, adding manganese dioxide loaded manganese ferrite into thallium-containing wastewater, and adsorbing thallium in the wastewater by using a magnetic adsorption material;
step 2, an external magnetic field attracts the magnetic adsorption material attached with thallium;
and 3, performing solid-liquid separation, wherein the supernatant is the treated water from which the thallium element is removed.
Further, thallium element is recovered by the magnetic adsorbent: and desorbing the magnetic adsorption material adsorbed with thallium, and enriching thallium elements adsorbed by the magnetic adsorption material into desorption solution.
The invention has the technical effects that: the thallium ion removal in the wastewater can reach the national standard of 'thallium pollutant emission Standard for Industrial wastewater' (DB 44/1989-2017), and thallium element can be recovered.
Detailed Description
The invention is further illustrated by the following examples:
example 1
The magnetic adsorption material comprises manganese ferrite, manganese dioxide and manganese dioxide (MnO)2) With manganese ferrite (MnFe)2O4) The mass ratio of (A) to (B) is 1: 5.
The preparation method of the magnetic adsorption material comprises the following steps: dissolving 12.10g (0.07mol) of manganese acetate in 50ml of distilled water, adding 29.42g (0.14mol) of citric acid for dissolving, adding water for diluting to 100ml, adjusting the pH value of the solution to be between 5.0 and 6.0 by using ammonia water, adding 30.45g of manganese ferrite, stirring uniformly, carrying out ultrasonic treatment for 30min to uniformly mix the manganese ferrite, paving the mixture in a culture dish, putting the culture dish into an oven for drying, grinding the mixture, carrying out roasting treatment to obtain manganese dioxide loaded manganese ferrite, and storing the manganese dioxide loaded manganese ferrite for later use while recording the production.
Wastewater sample 1: selecting the desulfurization wastewater with the thallium ion content of 950.0 mu g/L and the pH value of 6-7 in the steel industry.
Preparation of the experiment: and (3) respectively adding 10mg, 20mg, 30mg, 40mg and 50mg of magnetic adsorption materials into five beakers filled with 100ml of desulfurization wastewater in the steel industry, standing for 40min, and detecting the thallium ion content of supernatant liquid in the five beakers. The detection result is as follows: the thallium ion content of the supernatant obtained after the treatment by adding 30mg and 40mg of magnetic adsorption materials is similar, and both the thallium ion content and the thallium ion content are below 0.05 mu g/L, and the pH value is 7.0-8.5, so that the addition of 350mg of magnetic adsorption materials in each liter of desulfurization wastewater in the steel industry can be determined to be appropriate.
The method for treating the wastewater sample 1 by using the magnetic adsorption material of the embodiment comprises the following steps:
step 1, adding the prepared magnetic adsorption material into the desulfurization wastewater of the steel industry for reaction, wherein the liquid medicine added into each liter of the desulfurization wastewater of the steel industry contains 350mg of the magnetic adsorption material, and the reaction time is 60 min.
Step 2, after the reaction is finished, externally applying a magnetic field of 0.2T to attract the magnetic adsorption material attached with thallium;
and 3, performing solid-liquid separation for 30min to separate the magnetic adsorption material attached with thallium, obtain treated water, and removing the external magnetic field.
And detecting the treated water by an inductively coupled plasma mass spectrometer, and measuring that the content of thallium ions is 0.039 mug/L.
Further, thallium element is recovered from the magnetic adsorbent having thallium adhered thereto: taking out the magnetic adsorption material attached with the thallium, adding nitric acid into the magnetic adsorption material attached with the thallium to adjust the pH value to 1.5, and carrying out desorption reaction for 30 min; and (3) attracting the desorbed magnetic adsorption material by an external magnetic field of 0.2T, and carrying out solid-liquid separation for 30min to obtain supernatant, namely the enriched recovery solution concentrated with the thallium element.
For the wastewater sample 1 of this example, the thallium concentration of the enriched recovery solution was 47.31mg/L, and the enrichment recovery rate was 99.6%.
Wastewater sample 2: the thallium content of the untreated wastewater of a certain zinc processing plant in south China is 6.6 mg/L.
Method for treating wastewater sample 2 using magnetic adsorbent material:
step 1, adding the prepared magnetic adsorption material into untreated wastewater of the zinc processing plant for reaction, wherein 3g of the magnetic adsorption material is added into each liter of wastewater, and the reaction time is 60 min.
Step 2, after the reaction is finished, externally applying a magnetic field of 1.0T to attract the magnetic adsorption material attached with thallium;
and 3, performing solid-liquid separation for 15min to separate the magnetic adsorption material attached with thallium, obtain treated water, and removing the external magnetic field.
The treated water was examined to find that the thallium ion content was 1.1. mu.g/L.
Further, thallium element is recovered from the magnetic adsorbent having thallium adhered thereto: taking out the magnetic adsorption material attached with the thallium, adding nitric acid into the magnetic adsorption material attached with the thallium to adjust the pH value to 1.5, and carrying out desorption reaction for 30 min; and (3) attracting the desorbed magnetic adsorption material by an external magnetic field of 1.0T, and carrying out solid-liquid separation for 15min to obtain supernatant, namely the enriched recovery solution concentrated with the thallium element.
For the wastewater sample 2 of this example, the thallium concentration of the enriched recovery solution was 329.29mg/L, and the enrichment recovery rate was 99.8%.
Wastewater sample 3: and (3) manually preparing the thallium-containing simulated wastewater, wherein the thallium content is 10 mg/L.
Method for treating wastewater sample 3 using magnetic adsorbent material:
step 1, adding the prepared magnetic adsorption material into simulated wastewater for reaction, wherein the amount of the magnetic adsorption material added in each liter of the simulated wastewater is 150mg, and the reaction time is 60 min.
Step 2, after the reaction is finished, externally applying a magnetic field of 2.0T to attract the magnetic adsorption material attached with thallium;
and 3, performing solid-liquid separation for 10min to separate the magnetic adsorption material attached with thallium, obtain treated water, and removing the external magnetic field.
The treated water was examined to find that the thallium ion content was 1.2. mu.g/L.
Further, thallium element is recovered from the magnetic adsorbent having thallium adhered thereto: taking out the magnetic adsorption material attached with the thallium, adding nitric acid into the magnetic adsorption material attached with the thallium to adjust the pH value to 1.5, and carrying out desorption reaction for 30 min; and (3) attracting the desorbed magnetic adsorption material by an external magnetic field of 2.0T, carrying out solid-liquid separation for 10min, and obtaining supernatant which is the enriched recovery liquid concentrated with the thallium element.
For the wastewater sample 3 of this example, the thallium concentration of the enriched recovery solution was 498.94mg/L, and the enrichment recovery rate was 99.8%.
Example 2
The magnetic adsorption material comprises manganese ferrite, manganese dioxide and manganese dioxide (MnO)2) With manganese ferrite (MnFe)2O4) The mass ratio of (A) to (B) is 1: 6.
The preparation method of the magnetic adsorption material comprises the following steps: dissolving 12.10g (0.07mol) of manganese acetate in 50ml of distilled water, adding 29.42g (0.14mol) of citric acid for dissolving, adding water for diluting to 100ml, adjusting the pH value of the solution to be between 5.0 and 6.0 by using ammonia water, adding 36.54g of manganese ferrite, uniformly stirring, carrying out ultrasonic treatment for 30min to uniformly mix, then spreading in a culture dish, putting in an oven for drying, grinding, carrying out roasting treatment to obtain manganese dioxide loaded manganese ferrite, storing for later use, and simultaneously recording production.
For wastewater sample 1: the wastewater sample 1 was treated with the magnetic adsorbent in the same manner as in example 1.
The treated water was examined to determine that the thallium ion content was 0.073. mu.g/L.
For the wastewater sample 1 of this example, the thallium concentration of the enriched recovery solution was 47.07mg/L, and the enrichment recovery rate was 99.1%.
For wastewater sample 2: the wastewater sample 2 was treated with the magnetic adsorbent in the same manner as in example 1.
The treated water was examined to find that the thallium ion content was 1.5. mu.g/L.
For the wastewater sample 2 of this example, the thallium concentration of the enriched recovery solution was 327.94mg/L, and the enrichment recovery rate was 99.4%.
For wastewater sample 3: the wastewater sample 3 was treated with the magnetic adsorbent in the same manner as in example 1.
The treated water was examined to find that the thallium ion content was 1.8. mu.g/L.
For the wastewater sample 3 of this example, the thallium concentration of the enriched recovery solution was 496.41mg/L, and the enrichment recovery rate was 99.3%.
Claims (5)
1. A magnetic adsorption material is characterized in that: manganese acetate is used as a raw material, manganese ferrite particles are used as a carrier, citric acid is used as a complexing agent, and manganese dioxide loaded manganese ferrite prepared by a sol-gel method is adopted.
2. The magnetic adsorption material of claim 1, wherein the manganese dioxide-supported manganese ferrite has a mass ratio of manganese dioxide to manganese ferrite of 1: 5-6.
3. A method for preparing the magnetic adsorbent material according to claim 1 or 2, wherein: dissolving manganese acetate in water, adding citric acid for dissolving and diluting, adding manganese ferrite, uniformly mixing, drying, crushing and roasting to obtain manganese dioxide loaded manganese ferrite.
4. A process for the treatment of thallium containing wastewater using the magnetic adsorbent material of claim 1 or 2 characterized by the following steps:
step 1, adding manganese dioxide loaded manganese ferrite into thallium-containing wastewater, and adsorbing thallium in the wastewater by using a magnetic adsorption material;
step 2, an external magnetic field attracts the magnetic adsorption material attached with thallium;
and 3, performing solid-liquid separation, wherein the supernatant is the treated water from which the thallium element is removed.
5. The process for treating thallium containing wastewater as claimed in claim 4, wherein the magnetic adsorbent material is characterized by the following: and adding acid into the magnetic adsorption material with the thallium attached to adjust the pH value, externally adding a magnetic field to attract the desorbed magnetic adsorption material, and performing solid-liquid separation to obtain supernatant, namely the enriched recovery solution concentrated with the thallium element.
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| CN101186340A (en) * | 2007-11-28 | 2008-05-28 | 吴江市方霞企业信息咨询有限公司 | Method for preparing manganese dioxide by sol-gel |
| CN104150540A (en) * | 2014-07-14 | 2014-11-19 | 河南大学 | Heavy metal ion adsorbent ferrite hollow spheres MFe2O4 |
| CN105688793A (en) * | 2016-01-25 | 2016-06-22 | 华东交通大学 | Preparation method of MnO2-based magnetic nano Fe3O4 heavy metal adsorbing material |
| CN106365240A (en) * | 2016-10-13 | 2017-02-01 | 上海大学 | Method for removing heavy metals in waste water by recycling magnetic composite adsorption materials (MnO2-Fe3O4) |
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| CN101186340A (en) * | 2007-11-28 | 2008-05-28 | 吴江市方霞企业信息咨询有限公司 | Method for preparing manganese dioxide by sol-gel |
| CN104150540A (en) * | 2014-07-14 | 2014-11-19 | 河南大学 | Heavy metal ion adsorbent ferrite hollow spheres MFe2O4 |
| CN105688793A (en) * | 2016-01-25 | 2016-06-22 | 华东交通大学 | Preparation method of MnO2-based magnetic nano Fe3O4 heavy metal adsorbing material |
| CN106365240A (en) * | 2016-10-13 | 2017-02-01 | 上海大学 | Method for removing heavy metals in waste water by recycling magnetic composite adsorption materials (MnO2-Fe3O4) |
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