Preparation method and application of soil remediation agent based on zinc slag-Zn-MOF

Abstract

The invention discloses a preparation method of a soil remediation agent based on zinc slag-Zn-MOF.The preparation method comprises the steps that firstly, solid waste zinc slag is adopted for preparing zinc slag Zn-MOF, then the zinc slag Zn-MOF serves as a carrier, sodium percarbonate and acid-containing ferrous sulfate are loaded on the zinc slag Zn-MOF, finally, the zinc slag Zn-MOF loaded with the sodium percarbonate and the zinc slag Zn-MOF loaded with the acid-containing ferrous sulfate are mixed according to the mass ratio of 1: (1-7), and the soil remediation agent is obtained. The soil remediation agent is obtained. Compared with the soil remediation agent in the prior art, the solid waste zinc slag is adopted as the main preparation raw material of the carrier material, resource utilization of the solid waste is achieved, waste can be turned into wealth, the waste treatment cost can be reduced, and the environmental pressure can be relieved; the prepared soil remediation agent has the efficient adsorption capacity of MOF and the strong oxidation performance of sodium percarbonate, and has a good remediation effect on organic contaminated soil.

Description

Technical Field

[0001] The present invention belongs to the field of environmental geotechnical engineering, and in particular relates to a preparation method of a soil remediation agent based on zinc slag-Zn-MOF and an application thereof. Background Art

[0002] With the increase of industrial activities, the problem of organic contaminated soil has become increasingly prominent. For the remediation of organic soil pollution, the common methods currently include physical remediation, chemical remediation and biological remediation. Chemical remediation has become one of the important remediation methods due to its fast processing speed and high efficiency. In chemical remediation technology, sodium percarbonate, as a commonly used oxidant, can effectively oxidize and decompose organic pollutants by releasing hydrogen peroxide ions. However, the direct use of sodium percarbonate has problems such as difficulty in control, fast reaction speed and difficulty in sustainability.

[0003] To solve these problems, loading sodium percarbonate on a solid carrier is an effective strategy. Metal-organic frameworks (MOFs) are excellent carrier materials due to their high specific surface area, adjustable structure, and good chemical stability. In particular, zinc-based MOFs (Zn-MOFs) have attracted attention not only for their potential applications in environmental remediation, but also because zinc is an essential trace element for organisms, and its environmental friendliness is particularly important in the remediation process.

[0004] On the other hand, zinc slag is the main solid waste generated in the zinc smelting process, but its resource utilization is currently insufficient, and the accumulation of solid waste has brought serious environmental pressure.

[0005] Based on this, the present invention proposes a concept of synthesizing Zn-MOF using zinc slag and loading the repair agent on it to form a new soil repair agent. The agent can combine the high-efficiency adsorption capacity of MOF and the strong oxidation performance of sodium percarbonate, providing a new idea for the repair of organic contaminated soil. Summary of the invention

[0006] The purpose of the present invention is to solve the deficiencies of the prior art and to provide a method for preparing a soil remediation agent based on zinc slag-Zn-MOF. The soil remediation agent prepared by the method has an excellent remediation effect on organic contaminated soil.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A method for preparing a soil remediation agent based on zinc slag-Zn-MOF comprises the following steps:

[0009] (1) crushing the zinc slag, sieving it, and then performing a heat treatment, cooling it after the treatment, adding concentrated sulfuric acid and stirring to mix it evenly, and finally separating the solid from the liquid to obtain a liquid product;

[0010] (2) adding sodium hydroxide to the liquid product until the pH value of the system is 8 to obtain zinc hydroxide precipitate, washing and calcining the precipitate to obtain zinc oxide, and mixing the zinc oxide with a sulfuric acid solution to obtain a zinc sulfate solution;

[0011] (3) dissolving 2-amino-tert-butyl alcohol in dimethylformamide to obtain a 2-amino-tert-butyl alcohol solution, adding the 2-amino-tert-butyl alcohol solution to the zinc sulfate solution obtained in step (2), ultrasonically stirring and uniformly obtaining a mixed solution, and after solid-liquid separation, washing the obtained solid, then freeze-drying, and finally grinding and sieving to obtain zinc slag Zn-MOF;

[0012] (4) uniformly mixing the zinc slag Zn-MOF and the sodium percarbonate solution, and washing and freeze-drying the obtained mixed solution after solid-liquid separation to obtain the zinc slag Zn-MOF loaded with sodium percarbonate;

[0013] (5) mixing ferrous sulfate, citric acid and deionized water to obtain an acid-containing ferrous sulfate solution, and uniformly mixing the acid-containing ferrous sulfate solution with the zinc slag Zn-MOF, and washing and freeze-drying the obtained mixed solution after solid-liquid separation to obtain the zinc slag Zn-MOF loaded with acid-containing ferrous sulfate;

[0014] (6) The sodium percarbonate-loaded zinc slag Zn-MOF prepared in step (4) and the acid-containing ferrous sulfate-loaded zinc slag Zn-MOF prepared in step (5) are uniformly mixed to obtain.

[0015] Furthermore, in step (1), the heat treatment temperature is 220-280° C. and the time is 40-50 hours.

[0016] Furthermore, in step (1), the mass ratio of the zinc slag to concentrated sulfuric acid is 1:(1.5-3).

[0017] Furthermore, in steps (1) and (3), the stirring speed is 70 to 90 r / min, and the stirring time is 30 to 60 min.

[0018] Furthermore, in step (2), the calcination temperature is 550-650° C. and the calcination time is 6-10 hours.

[0019] Furthermore, in step (3), the mass ratio of 2-amino-tert-butyl alcohol to zinc oxide is 1:(1-5).

[0020] Furthermore, in steps (3), (4) and (5), the freeze-drying temperature is -50°C.

[0021] Furthermore, in step (4), the mass ratio of the zinc slag Zn-MOF to sodium percarbonate is 1.5:1.

[0022] Furthermore, in step (5), the mass ratio of ferrous sulfate to citric acid is (1.1-1.5):1, and the mass ratio of zinc slag Zn-MOF to ferrous sulfate is 1:(2-4).

[0023] Furthermore, in step (6), the mass ratio of the zinc slag Zn-MOF loaded with sodium percarbonate to the zinc slag Zn-MOF loaded with acid-containing ferrous sulfate is 1:(1-7).

[0024] Application of the soil remediation agent prepared by the above method in remediating organic contaminated soil: air-dry the organic contaminated soil and remove large stones, then test the moisture content and organic pollutant concentration of the organic contaminated soil, add the soil remediation agent prepared by the above method according to the tested organic pollutant concentration, stir evenly and add deionized water to adjust the moisture content to 24-28%, and maintain for 7 days to obtain the remediated soil;

[0025] The amount of soil remediation agent added is determined according to the concentration of organic pollutants, specifically: when the concentration of organic pollutants is ≤4000mg / kg, the amount of soil remediation agent added is 2% of the total mass of organic polluted soil; when the concentration of organic pollutants is 4000mg / kg<the concentration of organic pollutants is ≤8000mg / kg, the amount of soil remediation agent added is 4% of the total mass of organic polluted soil; when the concentration of organic pollutants is 8000mg / kg<the concentration of organic pollutants is ≤12000mg / kg, the amount of soil remediation agent added is 6% of the total mass of organic polluted soil; when the concentration of organic pollutants is >12000mg / kg, the amount of soil remediation agent added needs to be increased by 2% for every 4000mg / kg increase in concentration.

[0026] Beneficial effects of the present invention: The present invention provides a method for preparing a soil remediation agent based on zinc slag-Zn-MOF, firstly using zinc slag to prepare zinc slag Zn-MOF, then using it as a carrier to load sodium percarbonate and acid-containing ferrous sulfate respectively, and finally mixing the zinc slag Zn-MOF loaded with sodium percarbonate and the zinc slag Zn-MOF loaded with acid-containing ferrous sulfate in a specific ratio to obtain a soil remediation agent. Compared with the soil remediation agent in the prior art, the present invention has the following advantages:

[0027] 1) The present invention uses solid waste zinc slag as the main raw material for preparing the carrier material, thereby realizing the resource utilization of solid waste, which can not only turn waste into treasure, but also reduce waste treatment costs and alleviate environmental pressure;

[0028] 2) The soil remediation agent prepared by the present invention has both the high-efficiency adsorption capacity of MOF and the strong oxidation performance of sodium percarbonate, and has a good remediation effect on organically contaminated soil;

[0029] 3) The present invention uses a loading agent to load sodium percarbonate and ferrous sulfate, which can enable the reaction to proceed continuously, achieve continuous repair of organic pollutants, and enhance the repair efficiency. DETAILED DESCRIPTION

[0030] The technical solution of the present invention is described in detail below in conjunction with specific embodiments, but the protection scope of the present invention is not limited to the embodiments.

[0031] Example 1

[0032] A method for preparing a soil remediation agent based on zinc slag-Zn-MOF comprises the following steps:

[0033] (1) crushing the zinc slag and passing it through a 2 mm sieve, taking 200 g of the sieved zinc slag and heat treating it at 250° C. in a muffle furnace for 48 h, cooling it, adding 400 g of concentrated sulfuric acid, stirring it at a speed of 75 r / min for 35 min, and then performing solid-liquid separation to obtain a liquid product;

[0034] (2) adding sodium hydroxide to the liquid product until the pH value of the system reaches 8 to obtain zinc hydroxide precipitate, washing the precipitate 5 times, and calcining the precipitate at 600° C. for 8 h to obtain zinc oxide, and mixing 80 g of zinc oxide with 1200 mL of a 1 mol / L sulfuric acid solution to obtain a zinc sulfate solution;

[0035] (3) 80 g of 2-amino tert-butanol was dissolved in 100 g of dimethylformamide to obtain a 2-amino tert-butanol solution, which was added to the zinc sulfate solution obtained in step (2), and ultrasonicated and stirred evenly (ultrasonic power of 110 W, ultrasonic time of 35 min, stirring speed of 75 r / min, stirring time of 35 min) to obtain a mixed solution, and then solid-liquid separation was performed, and the obtained solid was washed with dimethylformamide for 5 times, and then freeze-dried at -50°C for 48 h, and finally ground through a 0.075 mm sieve to obtain zinc slag Zn-MOF;

[0036] (4) 25 g of sodium percarbonate was mixed with 100 g of deionized water to obtain a sodium percarbonate solution, which was then mixed evenly with 37.5 g of zinc slag Zn-MOF and placed in a horizontal oscillator for 24 h. After the obtained mixed solution was separated into solid and liquid, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with sodium percarbonate;

[0037] (5) 25 g of ferrous sulfate, 18.75 g of citric acid and 100 g of deionized water were mixed to obtain an acid-containing ferrous sulfate solution, which was mixed evenly with 10 g of zinc slag Zn-MOF. After the obtained mixed solution was solid-liquid separated, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with acid-containing ferrous sulfate;

[0038] (6) The sodium percarbonate-loaded zinc slag Zn-MOF prepared in step (4) and the acid-containing ferrous sulfate-loaded zinc slag Zn-MOF prepared in step (5) are uniformly mixed in a mass ratio of 1:2 to obtain.

[0039] Example 2

[0040] A method for preparing a soil remediation agent based on zinc slag-Zn-MOF comprises the following steps:

[0041] (1) crushing the zinc slag and passing it through a 2 mm sieve, taking 200 g of the sieved zinc slag and heat treating it at 250° C. in a muffle furnace for 48 h, cooling it, adding 400 g of concentrated sulfuric acid, stirring it at a speed of 75 r / min for 35 min, and then performing solid-liquid separation to obtain a liquid product;

[0042] (2) adding sodium hydroxide to the liquid product until the pH value of the system reaches 8 to obtain zinc hydroxide precipitate, washing the precipitate 5 times, and calcining the precipitate at 600° C. for 8 h to obtain zinc oxide, and mixing 80 g of zinc oxide with 1200 mL of a 1 mol / L sulfuric acid solution to obtain a zinc sulfate solution;

[0043] (3) Dissolve 26.67 g of 2-amino-tert-butanol in 100 g of dimethylformamide to obtain a 2-amino-tert-butanol solution, add the 2-amino-tert-butanol solution to the zinc sulfate solution obtained in step (2), ultrasonicate and stir evenly (ultrasonic power of 110 W, ultrasonic time of 35 min, stirring speed of 75 r / min, stirring time of 35 min) to obtain a mixed solution, then separate the solid from the liquid, wash the obtained solid with dimethylformamide 5 times, freeze-dry at -50 ° C for 48 h, and finally grind through a 0.075 mm sieve to obtain zinc slag Zn-MOF;

[0044] (4) 25 g of sodium percarbonate was mixed with 100 g of deionized water to obtain a sodium percarbonate solution, which was then mixed evenly with 37.5 g of zinc slag Zn-MOF and placed in a horizontal oscillator for 24 h. After the obtained mixed solution was separated into solid and liquid, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with sodium percarbonate;

[0045] (5) 25 g of ferrous sulfate, 18.75 g of citric acid and 100 g of deionized water were mixed to obtain an acid-containing ferrous sulfate solution, which was mixed evenly with 10 g of zinc slag Zn-MOF. After the obtained mixed solution was solid-liquid separated, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with acid-containing ferrous sulfate;

[0046] (6) The sodium percarbonate-loaded zinc slag Zn-MOF prepared in step (4) and the acid-containing ferrous sulfate-loaded zinc slag Zn-MOF prepared in step (5) are uniformly mixed in a mass ratio of 1:2 to obtain.

[0047] Example 3

[0048] A method for preparing a soil remediation agent based on zinc slag-Zn-MOF comprises the following steps:

[0049] (1) crushing the zinc slag and passing it through a 2 mm sieve, taking 200 g of the sieved zinc slag and heat treating it at 250° C. in a muffle furnace for 48 h, cooling it, adding 400 g of concentrated sulfuric acid, stirring it at a speed of 75 r / min for 35 min, and then performing solid-liquid separation to obtain a liquid product;

[0050] (2) adding sodium hydroxide to the liquid product until the pH value of the system reaches 8 to obtain zinc hydroxide precipitate, washing the precipitate 5 times, and calcining the precipitate at 600° C. for 8 h to obtain zinc oxide, and mixing 80 g of zinc oxide with 1200 mL of a 1 mol / L sulfuric acid solution to obtain a zinc sulfate solution;

[0051] (3) dissolving 16 g of 2-amino-tert-butyl alcohol in 100 g of dimethylformamide to obtain a 2-amino-tert-butyl alcohol solution, adding the 2-amino-tert-butyl alcohol solution to the zinc sulfate solution obtained in step (2), ultrasonically stirring and uniformly (ultrasonic power of 110 W, ultrasonic time of 35 min, stirring speed of 75 r / min, stirring time of 35 min) to obtain a mixed solution, and then separating the solid from the liquid, washing the obtained solid with dimethylformamide for 5 times, and then freeze-drying it at -50°C for 48 h, and finally grinding it through a 0.075 mm sieve to obtain zinc slag Zn-MOF;

[0052] (4) 25 g of sodium percarbonate was mixed with 100 g of deionized water to obtain a sodium percarbonate solution, which was then mixed evenly with 37.5 g of zinc slag Zn-MOF and placed in a horizontal oscillator for 24 h. After the obtained mixed solution was separated into solid and liquid, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with sodium percarbonate;

[0053] (5) 25 g of ferrous sulfate, 18.75 g of citric acid and 100 g of deionized water were mixed to obtain an acid-containing ferrous sulfate solution, which was mixed evenly with 10 g of zinc slag Zn-MOF. After the obtained mixed solution was solid-liquid separated, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with acid-containing ferrous sulfate;

[0054] (6) The sodium percarbonate-loaded zinc slag Zn-MOF prepared in step (4) and the acid-containing ferrous sulfate-loaded zinc slag Zn-MOF prepared in step (5) are uniformly mixed in a mass ratio of 1:2 to obtain.

[0055] Example 4

[0056] A method for preparing a soil remediation agent based on zinc slag-Zn-MOF comprises the following steps:

[0057] (1) crushing the zinc slag and passing it through a 2 mm sieve, taking 200 g of the sieved zinc slag and heat treating it at 250° C. in a muffle furnace for 48 h, cooling it, adding 400 g of concentrated sulfuric acid, stirring it at a speed of 75 r / min for 35 min, and then performing solid-liquid separation to obtain a liquid product;

[0058] (2) adding sodium hydroxide to the liquid product until the pH value of the system reaches 8 to obtain zinc hydroxide precipitate, washing the precipitate 5 times, and calcining the precipitate at 600° C. for 8 h to obtain zinc oxide, and mixing 80 g of zinc oxide with 1200 mL of a 1 mol / L sulfuric acid solution to obtain a zinc sulfate solution;

[0059] (3) 80 g of 2-amino tert-butanol was dissolved in 100 g of dimethylformamide to obtain a 2-amino tert-butanol solution, which was added to the zinc sulfate solution obtained in step (2), and ultrasonicated and stirred evenly (ultrasonic power of 110 W, ultrasonic time of 35 min, stirring speed of 75 r / min, stirring time of 35 min) to obtain a mixed solution, and then solid-liquid separation was performed, and the obtained solid was washed with dimethylformamide for 5 times, and then freeze-dried at -50°C for 48 h, and finally ground through a 0.075 mm sieve to obtain zinc slag Zn-MOF;

[0060] (4) 25 g of sodium percarbonate was mixed with 100 g of deionized water to obtain a sodium percarbonate solution, which was then mixed evenly with 37.5 g of zinc slag Zn-MOF and placed in a horizontal oscillator for 24 h. After the obtained mixed solution was separated into solid and liquid, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with sodium percarbonate;

[0061] (5) 25 g of ferrous sulfate, 18.75 g of citric acid and 100 g of deionized water were mixed to obtain an acid-containing ferrous sulfate solution, which was mixed evenly with 10 g of zinc slag Zn-MOF. After the obtained mixed solution was solid-liquid separated, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with acid-containing ferrous sulfate;

[0062] (6) The sodium percarbonate-loaded zinc slag Zn-MOF prepared in step (4) and the acid-containing ferrous sulfate-loaded zinc slag Zn-MOF prepared in step (5) are uniformly mixed in a mass ratio of 1:4 to obtain.

[0063] Example 5

[0064] A method for preparing a soil remediation agent based on zinc slag-Zn-MOF comprises the following steps:

[0065] (1) crushing the zinc slag and passing it through a 2 mm sieve, taking 200 g of the sieved zinc slag and heat treating it at 250° C. in a muffle furnace for 48 h, cooling it, adding 400 g of concentrated sulfuric acid, stirring it at a speed of 75 r / min for 35 min, and then performing solid-liquid separation to obtain a liquid product;

[0066] (2) adding sodium hydroxide to the liquid product until the pH value of the system reaches 8 to obtain zinc hydroxide precipitate, washing the precipitate 5 times, and calcining the precipitate at 600° C. for 8 h to obtain zinc oxide, and mixing 80 g of zinc oxide with 1200 mL of a 1 mol / L sulfuric acid solution to obtain a zinc sulfate solution;

[0067] (3) Dissolve 26.67 g of 2-amino-tert-butanol in 100 g of dimethylformamide to obtain a 2-amino-tert-butanol solution, add the 2-amino-tert-butanol solution to the zinc sulfate solution obtained in step (2), ultrasonicate and stir evenly (ultrasonic power of 110 W, ultrasonic time of 35 min, stirring speed of 75 r / min, stirring time of 35 min) to obtain a mixed solution, then separate the solid from the liquid, wash the obtained solid with dimethylformamide 5 times, freeze-dry at -50 ° C for 48 h, and finally grind through a 0.075 mm sieve to obtain zinc slag Zn-MOF;

[0068] (4) 25 g of sodium percarbonate was mixed with 100 g of deionized water to obtain a sodium percarbonate solution, which was then mixed evenly with 37.5 g of zinc slag Zn-MOF and placed in a horizontal oscillator for 24 h. After the obtained mixed solution was separated into solid and liquid, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with sodium percarbonate;

[0069] (5) 25 g of ferrous sulfate, 18.75 g of citric acid and 100 g of deionized water were mixed to obtain an acid-containing ferrous sulfate solution, which was mixed evenly with 10 g of zinc slag Zn-MOF. After the obtained mixed solution was solid-liquid separated, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with acid-containing ferrous sulfate;

[0070] (6) The sodium percarbonate-loaded zinc slag Zn-MOF prepared in step (4) and the acid-containing ferrous sulfate-loaded zinc slag Zn-MOF prepared in step (5) are uniformly mixed in a mass ratio of 1:4 to obtain.

[0071] Example 6

[0072] A method for preparing a soil remediation agent based on zinc slag-Zn-MOF comprises the following steps:

[0073] (1) crushing the zinc slag and passing it through a 2 mm sieve, taking 200 g of the sieved zinc slag and heat treating it at 250° C. in a muffle furnace for 48 h, cooling it, adding 400 g of concentrated sulfuric acid, stirring it at a speed of 75 r / min for 35 min, and then performing solid-liquid separation to obtain a liquid product;

[0074] (2) adding sodium hydroxide to the liquid product until the pH value of the system reaches 8 to obtain zinc hydroxide precipitate, washing the precipitate 5 times, and calcining the precipitate at 600° C. for 8 h to obtain zinc oxide, and mixing 80 g of zinc oxide with 1200 mL of a 1 mol / L sulfuric acid solution to obtain a zinc sulfate solution;

[0075] (3) dissolving 16 g of 2-amino-tert-butyl alcohol in 100 g of dimethylformamide to obtain a 2-amino-tert-butyl alcohol solution, adding the 2-amino-tert-butyl alcohol solution to the zinc sulfate solution obtained in step (2), ultrasonically stirring and uniformly (ultrasonic power of 110 W, ultrasonic time of 35 min, stirring speed of 75 r / min, stirring time of 35 min) to obtain a mixed solution, and then separating the solid from the liquid, washing the obtained solid with dimethylformamide for 5 times, and then freeze-drying it at -50°C for 48 h, and finally grinding it through a 0.075 mm sieve to obtain zinc slag Zn-MOF;

[0076] (4) 25 g of sodium percarbonate was mixed with 100 g of deionized water to obtain a sodium percarbonate solution, which was then mixed evenly with 37.5 g of zinc slag Zn-MOF and placed in a horizontal oscillator for 24 h. After the obtained mixed solution was separated into solid and liquid, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with sodium percarbonate;

[0077] (5) 25 g of ferrous sulfate, 18.75 g of citric acid and 100 g of deionized water were mixed to obtain an acid-containing ferrous sulfate solution, which was mixed evenly with 10 g of zinc slag Zn-MOF. After the obtained mixed solution was solid-liquid separated, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with acid-containing ferrous sulfate;

[0078] (6) The sodium percarbonate-loaded zinc slag Zn-MOF prepared in step (4) and the acid-containing ferrous sulfate-loaded zinc slag Zn-MOF prepared in step (5) are uniformly mixed in a mass ratio of 1:4 to obtain.

[0079] Example 7

[0080] A method for preparing a soil remediation agent based on zinc slag-Zn-MOF comprises the following steps:

[0081] (1) crushing the zinc slag and passing it through a 2 mm sieve, taking 200 g of the sieved zinc slag and heat treating it at 250° C. in a muffle furnace for 48 h, cooling it, adding 400 g of concentrated sulfuric acid, stirring it at a speed of 75 r / min for 35 min, and then performing solid-liquid separation to obtain a liquid product;

[0082] (2) adding sodium hydroxide to the liquid product until the pH value of the system reaches 8 to obtain zinc hydroxide precipitate, washing the precipitate 5 times, and calcining the precipitate at 600° C. for 8 h to obtain zinc oxide, and mixing 80 g of zinc oxide with 1200 mL of a 1 mol / L sulfuric acid solution to obtain a zinc sulfate solution;

[0083] (3) 80 g of 2-amino tert-butanol was dissolved in 100 g of dimethylformamide to obtain a 2-amino tert-butanol solution, which was added to the zinc sulfate solution obtained in step (2), and ultrasonicated and stirred evenly (ultrasonic power of 110 W, ultrasonic time of 35 min, stirring speed of 75 r / min, stirring time of 35 min) to obtain a mixed solution, and then solid-liquid separation was performed, and the obtained solid was washed with dimethylformamide for 5 times, and then freeze-dried at -50°C for 48 h, and finally ground through a 0.075 mm sieve to obtain zinc slag Zn-MOF;

[0084] (4) 25 g of sodium percarbonate was mixed with 100 g of deionized water to obtain a sodium percarbonate solution, which was then mixed evenly with 37.5 g of zinc slag Zn-MOF and placed in a horizontal oscillator for 24 h. After the obtained mixed solution was separated into solid and liquid, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with sodium percarbonate;

[0085] (5) 25 g of ferrous sulfate, 18.75 g of citric acid and 100 g of deionized water were mixed to obtain an acid-containing ferrous sulfate solution, which was mixed evenly with 10 g of zinc slag Zn-MOF. After the obtained mixed solution was solid-liquid separated, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with acid-containing ferrous sulfate;

[0086] (6) The sodium percarbonate-loaded zinc slag Zn-MOF prepared in step (4) and the acid-containing ferrous sulfate-loaded zinc slag Zn-MOF prepared in step (5) are uniformly mixed in a mass ratio of 1:6 to obtain.

[0087] Example 8

[0088] A method for preparing a soil remediation agent based on zinc slag-Zn-MOF comprises the following steps:

[0089] (1) crushing the zinc slag and passing it through a 2 mm sieve, taking 200 g of the sieved zinc slag and heat treating it at 250° C. in a muffle furnace for 48 h, cooling it, adding 400 g of concentrated sulfuric acid, stirring it at a speed of 75 r / min for 35 min, and then performing solid-liquid separation to obtain a liquid product;

[0090] (2) adding sodium hydroxide to the liquid product until the pH value of the system reaches 8 to obtain zinc hydroxide precipitate, washing the precipitate 5 times, and calcining the precipitate at 600° C. for 8 h to obtain zinc oxide, and mixing 80 g of zinc oxide with 1200 mL of a 1 mol / L sulfuric acid solution to obtain a zinc sulfate solution;

[0091] (3) Dissolve 26.67 g of 2-amino-tert-butanol in 100 g of dimethylformamide to obtain a 2-amino-tert-butanol solution, add the 2-amino-tert-butanol solution to the zinc sulfate solution obtained in step (2), ultrasonicate and stir evenly (ultrasonic power of 110 W, ultrasonic time of 35 min, stirring speed of 75 r / min, stirring time of 35 min) to obtain a mixed solution, then separate the solid from the liquid, wash the obtained solid with dimethylformamide 5 times, freeze-dry at -50 ° C for 48 h, and finally grind through a 0.075 mm sieve to obtain zinc slag Zn-MOF;

[0092] (4) 25 g of sodium percarbonate was mixed with 100 g of deionized water to obtain a sodium percarbonate solution, which was then mixed evenly with 37.5 g of zinc slag Zn-MOF and placed in a horizontal oscillator for 24 h. After the obtained mixed solution was separated into solid and liquid, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with sodium percarbonate;

[0093] (5) 25 g of ferrous sulfate, 18.75 g of citric acid and 100 g of deionized water were mixed to obtain an acid-containing ferrous sulfate solution, which was mixed evenly with 10 g of zinc slag Zn-MOF. After the obtained mixed solution was solid-liquid separated, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with acid-containing ferrous sulfate;

[0094] (6) The sodium percarbonate-loaded zinc slag Zn-MOF prepared in step (4) and the acid-containing ferrous sulfate-loaded zinc slag Zn-MOF prepared in step (5) are uniformly mixed in a mass ratio of 1:6 to obtain.

[0095] Example 9

[0096] A method for preparing a soil remediation agent based on zinc slag-Zn-MOF comprises the following steps:

[0097] (1) crushing the zinc slag and passing it through a 2 mm sieve, taking 200 g of the sieved zinc slag and heat treating it at 250° C. in a muffle furnace for 48 h, cooling it, adding 400 g of concentrated sulfuric acid, stirring it at a speed of 75 r / min for 35 min, and then performing solid-liquid separation to obtain a liquid product;

[0098] (2) adding sodium hydroxide to the liquid product until the pH value of the system reaches 8 to obtain zinc hydroxide precipitate, washing the precipitate 5 times, and calcining the precipitate at 600° C. for 8 h to obtain zinc oxide, and mixing 80 g of zinc oxide with 1200 mL of a 1 mol / L sulfuric acid solution to obtain a zinc sulfate solution;

[0099] (3) dissolving 16 g of 2-amino-tert-butyl alcohol in 100 g of dimethylformamide to obtain a 2-amino-tert-butyl alcohol solution, adding the 2-amino-tert-butyl alcohol solution to the zinc sulfate solution obtained in step (2), ultrasonically stirring and uniformly (ultrasonic power of 110 W, ultrasonic time of 35 min, stirring speed of 75 r / min, stirring time of 35 min) to obtain a mixed solution, and then separating the solid from the liquid, washing the obtained solid with dimethylformamide for 5 times, and then freeze-drying it at -50°C for 48 h, and finally grinding it through a 0.075 mm sieve to obtain zinc slag Zn-MOF;

[0100] (4) 25 g of sodium percarbonate was mixed with 100 g of deionized water to obtain a sodium percarbonate solution, which was then mixed evenly with 37.5 g of zinc slag Zn-MOF and placed in a horizontal oscillator for 24 h. After the obtained mixed solution was separated into solid and liquid, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with sodium percarbonate;

[0101] (5) 25 g of ferrous sulfate, 18.75 g of citric acid and 100 g of deionized water were mixed to obtain an acid-containing ferrous sulfate solution, which was mixed evenly with 10 g of zinc slag Zn-MOF. After the obtained mixed solution was solid-liquid separated, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with acid-containing ferrous sulfate;

[0102] (6) The sodium percarbonate-loaded zinc slag Zn-MOF prepared in step (4) and the acid-containing ferrous sulfate-loaded zinc slag Zn-MOF prepared in step (5) are uniformly mixed in a mass ratio of 1:6 to obtain.

[0103] Comparative Example 1

[0104] A method for preparing a soil remediation agent: sodium percarbonate and ferrous sulfate are uniformly mixed in a mass ratio of 1:2 to obtain the agent.

[0105] Comparative Example 2

[0106] A method for preparing sodium percarbonate-loaded zinc slag Zn-MOF comprises the following steps:

[0107] (1) crushing the zinc slag and passing it through a 2 mm sieve, taking 200 g of the sieved zinc slag and heat treating it at 250° C. in a muffle furnace for 48 h, cooling it, adding 400 g of concentrated sulfuric acid, stirring it at a speed of 75 r / min for 35 min, and then performing solid-liquid separation to obtain a liquid product;

[0108] (2) adding sodium hydroxide to the liquid product until the pH value of the system reaches 8 to obtain zinc hydroxide precipitate, washing the precipitate 5 times, and calcining the precipitate at 600° C. for 8 h to obtain zinc oxide, and mixing 80 g of zinc oxide with 1200 mL of a 1 mol / L sulfuric acid solution to obtain a zinc sulfate solution;

[0109] (3) 80 g of 2-amino tert-butanol was dissolved in 100 g of dimethylformamide to obtain a 2-amino tert-butanol solution, which was added to the zinc sulfate solution obtained in step (2), and ultrasonicated and stirred evenly (ultrasonic power of 110 W, ultrasonic time of 35 min, stirring speed of 75 r / min, stirring time of 35 min) to obtain a mixed solution, and then solid-liquid separation was performed, and the obtained solid was washed with dimethylformamide for 5 times, and then freeze-dried at -50°C for 48 h, and finally ground through a 0.075 mm sieve to obtain zinc slag Zn-MOF;

[0110] (4) 25 g of sodium percarbonate was mixed with 100 g of deionized water to obtain a sodium percarbonate solution, which was then mixed evenly with 37.5 g of zinc slag Zn-MOF and placed in a horizontal oscillator for 24 h. After the obtained mixed solution was separated into a solid and liquid state, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain a zinc slag Zn-MOF loaded with sodium percarbonate.

[0111] Comparative Example 3

[0112] A method for preparing a soil remediation agent comprises the following steps:

[0113] (1) crushing the zinc slag and passing it through a 2 mm sieve, taking 200 g of the sieved zinc slag and heat treating it at 250° C. in a muffle furnace for 48 h, cooling it, adding 400 g of concentrated sulfuric acid, stirring it at a speed of 75 r / min for 35 min, and then performing solid-liquid separation to obtain a liquid product;

[0114] (2) adding sodium hydroxide to the liquid product until the pH value of the system reaches 8 to obtain zinc hydroxide precipitate, washing the precipitate 5 times, and calcining the precipitate at 600° C. for 8 h to obtain zinc oxide, and mixing 80 g of zinc oxide with 1200 mL of a 1 mol / L sulfuric acid solution to obtain a zinc sulfate solution;

[0115] (3) 80 g of 2-amino tert-butanol was dissolved in 100 g of dimethylformamide to obtain a 2-amino tert-butanol solution, which was added to the zinc sulfate solution obtained in step (2), and ultrasonicated and stirred evenly (ultrasonic power of 110 W, ultrasonic time of 35 min, stirring speed of 75 r / min, stirring time of 35 min) to obtain a mixed solution, and then solid-liquid separation was performed, and the obtained solid was washed with dimethylformamide for 5 times, and then freeze-dried at -50°C for 48 h, and finally ground through a 0.075 mm sieve to obtain zinc slag Zn-MOF;

[0116] (4) 25 g of sodium percarbonate was mixed with 100 g of deionized water to obtain a sodium percarbonate solution, which was then mixed evenly with 37.5 g of zinc slag Zn-MOF and placed in a horizontal oscillator for 24 h. After the obtained mixed solution was separated into solid and liquid, the solid product was washed 5 times with deionized water and freeze-dried at -50°C to obtain zinc slag Zn-MOF loaded with sodium percarbonate;

[0117] (5) The zinc slag Zn-MOF loaded with sodium percarbonate and ferrous sulfate are uniformly mixed in a mass ratio of 1:2 to obtain.

[0118] The soil remediation agents prepared in Examples 1-9 and Comparative Examples 1-3 were used to remediate petroleum hydrocarbon contaminated soil: 50 g of petroleum hydrocarbon contaminated soil was taken from a certain place, air-dried and large rocks removed, and the moisture content and petroleum hydrocarbon concentration of the contaminated soil were tested. The petroleum hydrocarbon concentration test was based on the Petroleum Hydrocarbons in Soil and Sediment (C 10 -C 40 ) was measured by gas chromatography (HJ 1021-2019), and the pollutant concentration was 8900 mg / kg. 2 g of soil remediation agent was added, stirred evenly, and deionized water was added to adjust the soil moisture content to 24-28%. After curing for 7 days, the remediated soil was obtained, and the concentration of petroleum hydrocarbons in the remediated soil was tested. The remediation efficiency of the soil remediation agent for petroleum hydrocarbon contaminated soil was calculated. The remediation efficiency was calculated according to the following formula:

[0119]

[0120] The repair efficiency test results are shown in Table 1:

[0121] Table 1

[0122]

[0123] It can be seen from the test results in Table 1 that compared with the soil remediation agents prepared in Comparative Examples 1-3, the soil remediation agents prepared in Examples 1-9 of the present invention have better remediation effects on petroleum hydrocarbon contaminated soil.

Claims

1. A method for preparing a soil remediation agent based on zinc slag-Zn-MOF, characterized in that: The steps include: (1) crushing the zinc slag, sieving it, and then performing a heat treatment, cooling it after the treatment, adding concentrated sulfuric acid and stirring to mix it evenly, and finally separating the solid from the liquid to obtain a liquid product; (2) adding sodium hydroxide to the liquid product until the pH value of the system is 8 to obtain zinc hydroxide precipitate, washing and calcining the precipitate to obtain zinc oxide, and mixing the zinc oxide with a sulfuric acid solution to obtain a zinc sulfate solution; (3) dissolving 2-amino-tert-butyl alcohol in dimethylformamide to obtain a 2-amino-tert-butyl alcohol solution, adding the 2-amino-tert-butyl alcohol solution to the zinc sulfate solution obtained in step (2), ultrasonically stirring and uniformly obtaining a mixed solution, and after solid-liquid separation, washing the obtained solid, then freeze-drying, and finally grinding and sieving to obtain zinc slag Zn-MOF; (4) uniformly mixing the zinc slag Zn-MOF and the sodium percarbonate solution, and washing and freeze-drying the obtained mixed solution after solid-liquid separation to obtain the zinc slag Zn-MOF loaded with sodium percarbonate; (5) mixing ferrous sulfate, citric acid and deionized water to obtain an acid-containing ferrous sulfate solution, and uniformly mixing the acid-containing ferrous sulfate solution with the zinc slag Zn-MOF, and washing and freeze-drying the obtained mixed solution after solid-liquid separation to obtain the zinc slag Zn-MOF loaded with acid-containing ferrous sulfate; (6) The sodium percarbonate-loaded zinc slag Zn-MOF prepared in step (4) and the acid-containing ferrous sulfate-loaded zinc slag Zn-MOF prepared in step (5) are uniformly mixed to obtain.

2. The method for preparing a soil remediation agent based on zinc slag-Zn-MOF according to claim 1, characterized in that: In step (1), the heat treatment temperature is 220-280° C. and the time is 40-50 hours.

3. The method for preparing the soil remediation agent based on zinc slag-Zn-MOF according to claim 1, characterized in that: In step (1), the mass ratio of the zinc slag to concentrated sulfuric acid is 1:(1.5-3).

4. The method for preparing the soil remediation agent based on zinc slag-Zn-MOF according to claim 1, characterized in that: In step (2), the calcination temperature is 550-650° C. and the calcination time is 6-10 hours.

5. The method for preparing the soil remediation agent based on zinc slag-Zn-MOF according to claim 1, characterized in that: In step (3), the mass ratio of 2-amino tert-butyl alcohol to zinc oxide is 1:(1-5).

6. The method for preparing the soil remediation agent based on zinc slag-Zn-MOF according to claim 1, characterized in that: In steps (3), (4) and (5), the freeze-drying temperature is -50°C.

7. The method for preparing the soil remediation agent based on zinc slag-Zn-MOF according to claim 1, characterized in that: In step (4), the mass ratio of the zinc slag Zn-MOF to sodium percarbonate is 1.5:

1.

8. The method for preparing the soil remediation agent based on zinc slag-Zn-MOF according to claim 1, characterized in that: In step (5), the mass ratio of ferrous sulfate to citric acid is (1.1-1.5):1, and the mass ratio of zinc slag Zn-MOF to ferrous sulfate is 1:(2-4).

9. The method for preparing the soil remediation agent based on zinc slag-Zn-MOF according to any one of claims 1 to 8, characterized in that: In step (6), the mass ratio of the zinc slag Zn-MOF loaded with sodium percarbonate to the zinc slag Zn-MOF loaded with acid-containing ferrous sulfate is 1:(1-7).

10. Use of the soil remediation agent prepared by the method according to any one of claims 1 to 9 in remediating organic contaminated soil, characterized in that: The organic contaminated soil was air-dried and large rocks were removed, and then the moisture content and organic pollutant concentration of the organic contaminated soil were tested. According to the tested organic pollutant concentration, the soil remediation agent prepared by the above method was added, stirred evenly, and deionized water was added to adjust the moisture content to 24-28%, and cured for 7 days to obtain the remediated soil; The amount of soil remediation agent added is determined according to the concentration of organic pollutants, specifically: when the concentration of organic pollutants is ≤4000mg / kg, the amount of soil remediation agent added is 2% of the total mass of organic polluted soil; when the concentration of organic pollutants is 4000mg / kg<the concentration of organic pollutants is ≤8000mg / kg, the amount of soil remediation agent added is 4% of the total mass of organic polluted soil; when the concentration of organic pollutants is 8000mg / kg<the concentration of organic pollutants is ≤12000mg / kg, the amount of soil remediation agent added is 6% of the total mass of organic polluted soil; when the concentration of organic pollutants is >12000mg / kg, the amount of soil remediation agent added needs to be increased by 2% for every 4000mg / kg increase in concentration.

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