WO2017075950A1

WO2017075950A1 - Method for preparing iron-ferrous sulfide composite

Info

Publication number: WO2017075950A1
Application number: PCT/CN2016/080692
Authority: WO
Inventors: 何锋; 谷亚威; 万顺利
Original assignee: 浙江工业大学
Priority date: 2015-11-06
Filing date: 2016-04-29
Publication date: 2017-05-11
Also published as: CN105414554A

Abstract

A method for preparing an iron-ferrous sulfide composite, comprising: mixing elemental sulfur powder and iron sulfide powder at a mass ratio of 1 : 5-60 or mixing pyrite powder and micron iron powder at a mass ratio of 1 : 5-60 to obtain a mixed raw material; putting the mixed raw material into a ball mill tank of a ball mill, wherein the ball mill tank is filled with grinding media, and the ball mill tank is in a vacuum environment or inert gas atmosphere; starting the ball mill for grinding at a speed of 400-4000 rpm for 2-30 hours; and separating the grinding media from a product after the grinding, to obtain an iron-ferrous sulfide composite having a particle size of 10 μm or below. This preparation method is simple, has low material costs, and does not use or generate poisonous and harmful dangerous chemicals. The prepared iron-ferrous sulfide composite can efficiently purify chlorine-containing organic pollutants and heavy metals in water, and is particularly suitable for in-situ remediation of polluted underground water.

Description

Preparation method of iron-ferrous sulfide composite

(1) Technical field

The invention relates to a preparation method of an iron-sulfur sulfide composite, and more particularly to a preparation method of an efficient and environmentally friendly iron-sulfur sulfide composite.

(2) Background technology

As an emerging in-situ remediation technology for groundwater, zero-valent iron has received extensive attention at home and abroad. However, there are still many problems in the practical application of zero-valent iron. For example, strong magnetism and high surface energy will make it aggregate into large particles, which will make some active sites unable to be effectively released, and the utilization rate of active components is very low. Meanwhile, zero A dense oxide film on the surface of the valence iron will greatly hinder the contact of the active ingredient with the target contaminant, thereby reducing the activity of zero-valent iron; in addition, the hydrophilic zero-valent iron has poor affinity with the hydrophobic organic pollutants in the solution. .

In order to overcome the shortcomings of the above-mentioned simple zero-valent iron in practical applications, domestic and foreign scholars have been trying to modify the surface of zero-valent iron or to compound with other substances. For example, Zhang et al [Treatment of chlorinated organic contaminants with nanoscale bimetallic particles. Catal. Today. 1998, 40 (4), 387-395.] after loading precious metals such as platinum, palladium, silver, etc., to zero-valent iron, zero-valent iron degrades organic The rate of contaminants has increased several times and the degradation products are simpler. Although precious metals such as platinum, palladium and silver can significantly increase the activity of zero-valent iron, the cost is high, and it is easy to cause secondary pollution when it is lost to the environmental medium.

In recent years, ferrous sulfide has gradually become a new type of zero-valent iron modifier. It has been found that the presence of ferrous sulfide can greatly enhance the degradation activity of zero-valent iron on pollutants [Enhanced reductive dechlorination of trichloroethylene by sulfidatednanoscalezerovalent iron.Water research 2015, 78, 144-53.; Facile Synthesis and Characterization of Fe/FeS Nanoparticles for Environmental Applications. ACS Appl Mater Interfaces 2011, 3(5), 1457-62.]. This is mainly due to two points: (1) the hydrophobicity of ferrous sulfide makes the ferrous sulfide-modified zero-valent iron easier to combine with organic pollutants; (2) ferrous sulfide is a semiconductor, its existence can be greatly improved The efficiency of electron transfer from zero-valent iron to target pollutants. Therefore, the ferrous sulfide-modified zero-valent iron has broad application prospects in the field of repairing actual polluted water bodies. However, the existing zero-valent iron-loaded ferrous sulfide or a combination of zero-valent iron and ferrous sulfide is prepared by a chemical method. The preparation methods are roughly divided into two categories: one is to first use iron as a precursor (ferrous salt). The hydride is reduced to zero-valent iron, then sulfide is added, and the sulfide forms ferrous sulfide with the remaining ferrous ions. Precipitated on the surface of zero-valent iron, eventually forming zero-valent iron-loaded ferrous sulfide. Second, a borohydride solution containing dithionite is added to the iron salt solution to form a complex of zero-valent iron and ferrous sulfide. Although the composite of iron and ferrous sulfide prepared by chemical method is small, the preparation process has many shortcomings: (1) the synthesis method is cumbersome; (2) the iron is easily oxidized during the synthesis; (3) the raw material cost is high. And a large amount of wastewater will be produced; (4) borohydride will generate hydrogen, and there is a certain risk in the synthesis process.

(3) Invention content

The object of the present invention is to overcome the deficiencies of the prior art chemical preparation of the iron-sulfur sulphide composite, and to provide a physical preparation method of the iron-sulfur ferrous complex which is simple, efficient, clean and safe in preparation process.

The invention discloses a physical preparation method of an iron-sulfur sulphide composite. The method is simple, efficient, clean and safe, and can effectively solve the deficiencies of the prior art to prepare iron and ferrous sulfide composite by chemical method.

The technical solution adopted by the invention is:

A method for preparing an iron-sulfur sulphide composite, wherein the method comprises the following steps: mixing elemental sulfur powder or iron sulfide powder or pyrite powder with micron-sized iron powder at a mass ratio of 1:5-60, and mixing the obtained raw materials It is placed in a ball mill tank of a ball mill. The ball mill tank is filled with grinding medium. The ball mill tank is filled with a vacuum environment or an inert gas atmosphere. The ball mill is turned on, the grinding speed is 400-4000 rpm, and the grinding is performed for 2 to 30 hours. After grinding, the grinding medium and the product are separated. The iron-sulfur sulfide composite is produced.

The micron-sized iron powder is iron powder having a particle diameter of less than 100 micrometers and can be directly purchased on the market.

The iron sulfide may be ferrous sulfide, ferrous sulfide, diiron trisulfide or the like.

The pyrite may be pyrite, pyrrhotite, pyrite, sulfur concentrate, Mackinawite, and the like.

The ball mill of the present invention may be a planetary ball mill, a vibratory ball mill, a sand mill or the like.

The ball mill tank is provided with a grinding medium which is an iron ball, a steel ball, a silicon nitride ball or a zirconia ball having a diameter of 0.15 mm to 10 mm, preferably a zirconia ball or a silicon nitride ball.

The amount of the grinding medium to be charged is generally 10 to 50%, preferably 15% to 20%, based on the volume of the cavity of the ball mill tank.

The inside of the ball mill tank is an inert gas atmosphere or a vacuum environment, preferably an inert gas atmosphere, and the inert gas may be nitrogen or argon.

After the grinding, the grinding medium and the product are separated, and the grinding medium and the product can be separated by a sieve under an inert gas atmosphere.

The iron-sulfur sulphide composite provided by the invention is a powdery particle, and can control the particle by adjusting the grinding time Grain size. The iron-iron sulfide composite particles obtained by the method of the present invention have a particle diameter of 50 nm to 10 μm.

The mass ratio of the elemental sulfur powder or iron sulfide powder or pyrite powder to the micron-sized iron powder is preferably 1:8 to 52, more preferably 1:9 to 18, and most preferably 1:17.5.

The grinding speed of the ball mill is preferably 500 to 3000 rpm, more preferably 500 to 1000 rpm.

The polishing time is preferably 5 to 30 hours.

Specifically, it is preferred that the method of the present invention is carried out according to the following steps: the elemental sulfur powder or the iron sulfide powder or the pyrite powder and the micron-sized iron powder are mixed at a mass ratio of 1:9 to 18, and the obtained mixed raw material is placed in a ball mill tank of a ball mill. Inside, the ball mill tank is filled with 10 to 50% of the grinding medium volume, the ball mill tank is an inert gas atmosphere, the ball mill is turned on, the grinding speed is 500-1000 rpm, and the grinding is performed for 5 to 30 hours. After grinding, the grinding medium and the product are separated, that is, Preparing the iron-ferrous sulfide composite; the micron-sized iron powder is iron powder having a particle diameter of less than 100 μm; and the grinding medium is an iron ball, a steel ball, a silicon nitride ball having a diameter of 0.15 mm to 10 mm or Zirconia balls.

The iron-sulfur sulphide composite prepared by the invention can be used for in situ repair of chlorinated organic pollutants and heavy metals in groundwater. The chlorine-containing organic pollutants may be vinyl chloride such as vinyl chloride, dichloroethylene, trichloroethylene or tetrachloroethylene, chloroethanes such as trichloroethane or tetrachloroethane, and carbon tetrachloride. The heavy metal may be hexavalent chromium, cadmium ions or the like.

The preparation method of the invention is simple, and the iron-sulfur sulfide composite can be obtained only by simple grinding. Compared with the chemical synthesis method, the toxic and harmful chemical raw materials are not used in the preparation process of the method, no waste water is generated, no dangerous gas is generated, and the raw materials are produced. Low cost and an environmentally friendly process. The iron-sulfur sulphide composite prepared by the method has high catalytic activity, can be quickly affinity with organic pollutants, and is continuously degraded, and finally is reduced to non-polluting ethane, ethylene, etc., and is very suitable for groundwater in situ. repair.

(4) Description of the drawings

The drawing is an X-ray diffraction pattern of the iron-sulfur sulfide composite prepared in Example 1.

(5) Specific implementation methods

The invention is further described below in conjunction with specific embodiments, but the scope of protection of the invention is not limited thereto.

Example 1

The iron-sulfur sulphide composite is prepared by a planetary ball mill. The steps are as follows: (1) A zirconia ball-milling bead having a volume of 20% (0.6 mm in diameter) is placed in a ball mill tank as a grinding medium; (2) 0.256 g single Sulfur powder and 2.244g of zero-valent iron powder (particle size 38μm ~ 74μm) (sulfur iron mass ratio 1:8.76) placed in the ball mill tank, and filled with nitrogen in the tank; (3) open the ball mill, will grind The speed was adjusted to 500 rpm and ground for 5 hours; (4) The iron-sulfur sulphide composite obtained was separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulfide composite.

Taking trichloroethylene as an example, the activity of the above materials was examined. Add 4.25g of iron-sulfur ferrous complex to the 425mL reagent bottle, top up with deionized water, cover with Teflon septum cover, then add trichloroethylene concentrate to control the initial trichloroethylene At a concentration of 10 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 5 h of reaction, the concentration of TCE decreased to 0.5 mg L ^-1 and the degradation rate was 95%.

Example 2

The iron-sulfur sulphide composite is prepared by a planetary ball mill. The steps are as follows: (1) 20% cavity volume of zirconia ball beads (particle size 0.6 mm) is placed in a ball mill tank as a grinding medium; (2) weighing 0.135g elemental sulfur powder and 2.365g of zero-valent iron powder (particle size 38μm to 74μm) (sulfur iron mass ratio: 1:17.5) are continuously stirred and mixed uniformly in the ball mill tank, and filled with nitrogen in the tank; (3) The ball mill was turned on, the grinding speed was adjusted to 500 rpm, and the grinding was carried out for 5 hours. (4) The obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking trichloroethylene as an example, the activity of the above materials was examined. Add 4.25g of iron-sulfur ferrous complex to the 425mL reagent bottle, top up with deionized water, cover with Teflon septum cover, then add trichloroethylene concentrate to control the initial trichloroethylene At a concentration of 10 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 5 h of reaction, the concentration of TCE decreased to 0.9 mg L ^-1 and the degradation rate was 91%.

Example 3

The iron-sulfur sulphide composite is prepared by a planetary ball mill. The steps are as follows: (1) 20% cavity volume of steel ball beads (particle size 0.8mm) is loaded into a ball mill tank as a grinding medium; (2) Weighing 0.069g elemental sulfur powder and 2.43g of zero-valent iron powder (particle size 38μm to 74μm) (sulfur iron mass ratio 1:35.2) are continuously stirred and mixed uniformly in the ball mill tank, filled with nitrogen in the tank; (3) open In a ball mill, the grinding speed was adjusted to 500 rpm and ground for 5 hours; (4) The obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking trichloroethylene as an example, the activity of the above materials was examined. Add 4.25g of iron-sulfur ferrous complex to the 425mL reagent bottle, fill it up with deionized water, cover with a lid with Teflon septum, and then control the trichloroethylene with trichloroethylene concentrate. The initial concentration was 10 mg L ^-1 and the reagent bottle was shaken on a shaker. After 5 h of reaction, the concentration of TCE decreased to 1.2 mg L ^-1 and the degradation rate was 88%.

Example 4

The iron-sulfur sulphide composite is prepared by a planetary ball mill. The steps are as follows: (1) 20% cavity volume of zirconia ball beads (particle size 0.6 mm) is placed in a ball mill tank as a grinding medium; (2) weighing 0.047g elemental sulfur powder and 2.45g of zero-valent iron powder (particle size 38 microns to 74 microns) (sulfur iron mass ratio 1:52.1) are placed in a ball mill tank and filled with nitrogen in the tank; (3) the ball mill is turned on, The grinding speed was adjusted to 500 rpm and ground for 5 hours; (4) The obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking trichloroethylene as an example, the activity of the above materials was examined. Add 4.25g of iron-sulfur ferrous complex to the 425mL reagent bottle, top up with deionized water, cover with Teflon septum cover, then add trichloroethylene concentrate to control the initial trichloroethylene At a concentration of 10 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 5 h of reaction, the concentration of TCE decreased to 1.6 mg L ^-1 and the degradation rate was 84%.

Example 5

The iron-sulfur sulphide composite is prepared by a planetary ball mill. The steps are as follows: (1) A steel ball bead of 20% cavity volume (particle size 0.6 mm) is placed in a ball mill tank as a grinding medium; (2) Weighing 0.135g of elemental sulfur powder and 2.365g of zero-valent iron powder (particle size 38 microns to 74 microns) (sulfur iron mass ratio of 1:17.5) are placed in a ball mill tank and filled with nitrogen in the tank; (3) the ball mill is turned on, The grinding speed was adjusted to 500 rpm and ground for 2 hours; (4) The obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking trichloroethylene as an example, the activity of the above materials was examined. Add 4.25g of iron-sulfur ferrous complex to the 425mL reagent bottle, top up with deionized water, cover with Teflon septum cover, then add trichloroethylene concentrate to control the initial trichloroethylene At a concentration of 10 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 5 h of reaction, the concentration of TCE decreased to 1.1 mg L ^-1 and the degradation rate was 89%.

Example 6

The iron-sulfur sulphide composite is prepared by a planetary ball mill. The steps are as follows: (1) 20% cavity volume of zirconia ball beads (particle size 6 mm) is placed in a ball mill tank as a grinding medium; (2) 0.135 is weighed g elemental sulfur powder and 2.365g of zero-valent iron powder (particle size 38 microns to 74 microns) (sulfur iron mass ratio of 1:17.5) are continuously stirred and mixed uniformly in the ball mill tank, and filled with nitrogen in the tank; (3) open Ball mill, the grinding speed is adjusted to 500 rpm, grinding for 10 hours; (4) under nitrogen atmosphere, using the sieve to separate the obtained particles and grinding media Off, that is, the finished iron-sulfur sulphide composite.

Taking trichloroethylene as an example, the activity of the above materials was examined. Add 4.25g of iron-sulfur ferrous complex to the 425mL reagent bottle, top up with deionized water, cover with Teflon septum cover, then add trichloroethylene concentrate to control the initial trichloroethylene At a concentration of 10 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 5 h of reaction, the concentration of TCE decreased to 0.8 mg L ^-1 and the degradation rate was 92%.

Example 7

The iron-sulfur sulphide composite is prepared by a planetary ball mill. The steps are as follows: (1) 20% cavity volume of zirconia ball beads (particle size 1 mm) is placed in a ball mill tank as a grinding medium; (2) 0.135 is weighed g elemental sulfur powder and 2.365g of zero-valent iron powder (particle size 38 microns to 74 microns) (sulfur iron mass ratio of 1:17.5) are continuously stirred and mixed uniformly in the ball mill tank, filled with nitrogen in the tank; (3) open the ball mill The grinding speed was adjusted to 500 rpm and ground for 20 hours; (4) The obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking trichloroethylene as an example, the activity of the above materials was examined. Add 4.25g of iron-sulfur ferrous complex to the 425mL reagent bottle, top up with deionized water, cover with Teflon septum cover, then add trichloroethylene concentrate to control the initial trichloroethylene At a concentration of 10 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 5 h of reaction, the concentration of TCE decreased to 0.4 mg L ^-1 and the degradation rate was 96%.

Example 8

The laboratory sand mill prepares the iron-ferrous sulfide composite by the following steps: (1) 20% cavity volume of zirconia ball beads (particle size 0.3mm) is loaded into the ball mill tank as grinding medium; (2) Take 0.135g of elemental sulfur powder and 2.365g of zero-valent iron powder (particle size 38μm to 74μm) (sulfur iron mass ratio: 1:17.5) in a ball mill tank, and fill the tank with nitrogen; (3) Turn on the ball mill The grinding speed was adjusted to 3000 rpm and ground for 30 hours; (4) The obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking trichloroethylene as an example, the activity of the above materials was examined. Add 4.25g of iron-sulfur ferrous complex to the 425mL reagent bottle, top up with deionized water, cover with Teflon septum cover, then add trichloroethylene concentrate to control the initial trichloroethylene At a concentration of 10 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 5 h of reaction, the concentration of TCE decreased to 0.2 mg L ^-1 and the degradation rate was 98%.

Example 9

The iron-sulfur sulphide composite is prepared by a planetary ball mill, and the steps are as follows: (1) 20% cavity body The zirconia ball beads (particle size 0.6mm) are placed in the ball mill tank as grinding media; (2) 0.256g elemental sulfur powder and 2.244g zero-valent iron powder (particle size 38 microns to 74 microns) (sulfur iron mass) The ratio is 1:8.76) placed in a ball mill jar and filled with nitrogen in the tank; (3) the ball mill is turned on, the grinding speed is adjusted to 500 rpm, and ground for 20 hours; (4) under a nitrogen atmosphere, a sieve is used. The particles are separated from the grinding media to obtain a finished iron-sulfur sulfide composite.

Taking heavy metal chromium as an example, the activity of the above materials was investigated. Add 3g of iron-sulfur ferrous complex to 300mL reagent bottle, fill it up with deionized water, cover with Teflon septum cover, and then add hexavalent chromium stock solution to control Cr(VI) initial At a concentration of 50 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 2 h of reaction, the concentration of Cr(VI) was 2.2 mg L ^-1 and the removal rate was 95.6%.

Example 10

The iron-sulfur sulphide composite is prepared by a planetary ball mill, and the steps are as follows: (1) 20% cavity volume of iron ball beads (particle size 0.6 mm) is placed in a ball mill tank as a grinding medium; (2) weighing 0.135g of elemental sulfur powder and 2.365g of zero-valent iron powder (particle size 38 microns to 74 microns) (sulfur iron mass ratio of 1:17.5) are placed in a ball mill tank and filled with nitrogen in the tank; (3) the ball mill is turned on, The grinding speed was adjusted to 500 rpm and ground for 20 hours; (4) The obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking heavy metal chromium as an example, the activity of the above materials was investigated. Add 3g of iron-sulfur composite in 300mL reagent bottle, fill it up with deionized water, cover with Teflon septum cover, then add hexavalent chromium stock solution to control the initial concentration of Cr(VI) For 50 mg L ^-1 , place the reagent bottle on the shaker and shake it. After 2 h of reaction, the concentration of Cr(VI) was 3 mg L ^-1 and the removal rate was 94%.

Example 11

FRITSCH planetary ball mill reinforced, preparation of iron-ferrous ferrous sulfide composite; (1) 20% cavity volume of zirconia ball beads (particle size 0.6mm) into the ball mill tank as grinding media; (2) weighing 0.069g of elemental sulfur powder and 2.43g of zero-valent iron powder (particle size 38 microns to 74 microns) (sulfur iron mass ratio 1:35.2) are placed in a ball mill tank and filled with nitrogen in the tank; (3) the ball mill is turned on, The grinding speed was adjusted to 1000 rpm and ground for 30 hours; (4) The obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking heavy metal chromium as an example, the activity of the above materials was investigated. Add 3g of iron-sulfur composite in 300mL reagent bottle, fill it up with deionized water, cover with Teflon septum cover, then add hexavalent chromium stock solution to control the initial concentration of Cr(VI) For 50 mg L ^-1 , place the reagent bottle on the shaker and shake it. After 2 h of reaction, the concentration of Cr(VI) was 4 mg L ^-1 and the removal rate was 92%.

Example 12

FRITSCH planetary ball mill reinforced, preparation of iron-ferrous ferrous sulfide composite; (1) 20% cavity volume of zirconia ball beads (particle size 0.6mm) into the ball mill tank as grinding media; (2) weighing Single 0.047g sulfur powder and 2.45g zero-valent iron powder (particle size 38μm ~ 74μm) (sulfur iron mass ratio 1:52.1) placed in the ball mill tank, and filled with nitrogen in the tank; (3) open the ball mill The grinding speed was adjusted to 1000 rpm and ground for 30 hours; (4) The obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking heavy metal chromium as an example, the activity of the above materials was investigated. Add 3g of iron-sulfur composite in 300mL reagent bottle, fill it up with deionized water, cover with Teflon septum cover, then add hexavalent chromium stock solution to control the initial concentration of Cr(VI) For 50 mg L ^-1 , place the reagent bottle on the shaker and shake it. After 2 h of reaction, the concentration of Cr(VI) was 5 mg L ^-1 and the removal rate was 90%.

Example 13

The iron-sulfur sulphide composite is prepared by a planetary ball mill mill. The steps are as follows: (1) a zirconia ball bead (particle size 0.6 mm) having a volume of 15% is placed in a ball mill tank as a grinding medium; (2) Weighing 0.256g of elemental sulfur powder and 2.244g of zero-valent iron powder (particle size 38μm to 74μm) (sulfur iron mass ratio 1:8.76) is placed in the ball mill tank, and the tank is filled with nitrogen; (3) open In a ball mill, the grinding speed was adjusted to 500 rpm and ground for 5 hours; (4) The obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking heavy metal cadmium as an example, the activity of the above materials was investigated. Add 3g of iron-iron sulfide complex in 300mL reagent bottle, fill it up with deionized water, cover with Teflon septum cover, then add cadmium ion stock solution to control the initial concentration of Cd(II) 50 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 2 h of reaction, the concentration of Cd(II) was 4 mg L ^-1 and the removal rate was 92%.

Example 14

The iron-sulfur sulphide composite is prepared by a planetary ball mill mill. The steps are as follows: (1) a zirconia ball bead (particle size 0.6 mm) having a volume of 15% is placed in a ball mill tank as a grinding medium; (2) Weigh 0.135g of elemental sulfur powder and 2.365g of zero-valent iron powder (particle size 38μm to 74μm) (sulfur iron mass ratio: 1:17.5) in a ball mill tank, and fill the tank with nitrogen; (3) open Ball mill, the grinding speed is adjusted to 500rpm, The grinding was carried out for 5 hours; (4) the obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking heavy metal cadmium as an example, the activity of the above materials was investigated. Add 3g of iron-iron sulfide complex in 300mL reagent bottle, fill it up with deionized water, cover with Teflon septum cover, then add cadmium ion stock solution to control the initial concentration of Cd(II) 50 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 2 h of reaction, the concentration of Cd(II) was 5 mg L ^-1 and the removal rate was 90%.

Example 15

The iron-sulfur sulphide composite is prepared by a planetary ball mill mill. The steps are as follows: (1) a zirconia ball bead (particle size 0.6 mm) having a volume of 20% is placed in a ball mill tank as a grinding medium; (2) Weigh 0.069g of elemental sulfur powder and 2.43g of zero-valent iron powder (particle size 38μm to 74μm) (sulfur iron mass ratio 1:35.2) in a ball mill tank, and fill the tank with nitrogen; (3) open In a ball mill, the grinding speed was adjusted to 500 rpm and ground for 5 hours; (4) The obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking heavy metal cadmium as an example, the activity of the above materials was investigated. Add 3g of iron-iron sulfide complex in 300mL reagent bottle, fill it up with deionized water, cover with Teflon septum cover, then add cadmium ion stock solution to control the initial concentration of Cd(II) 50 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 2 h of reaction, the concentration of Cd(II) was 5.4 mg L ^-1 and the removal rate was 89.2%.

Example 16

Laboratory sand mill to prepare iron-ferrous sulfide composite; (1) 20% cavity volume of silicon nitride ball beads (particle size 0.3mm) into the ball mill tank as grinding media; (2) weighing 0.135g of elemental sulfur powder and 2.365g of zero-valent iron powder (particle size 38 microns to 74 microns) (sulfur iron mass ratio of 1:17.5) are placed in a ball mill tank and filled with nitrogen in the tank; (3) the ball mill is turned on, The grinding speed was adjusted to 2000 rpm and ground for 10 hours; (4) The obtained granules were separated from the grinding medium by a sieve under a nitrogen atmosphere to obtain a finished iron-sulfur sulphide composite.

Taking heavy metal cadmium as an example, the activity of the above materials was investigated. Add 3g of iron-iron sulfide complex in 300mL reagent bottle, fill it up with deionized water, cover with Teflon septum cover, then add cadmium ion stock solution to control the initial concentration of Cd(II) 50mg L ^-1, reagent bottle was shaken on a shaker. The concentration of Cd(II) in the reagent bottle was monitored periodically. After 2 h of reaction, the concentration of Cd(II) was 3.85 mg L ^-1 , and the removal rate was 92.3%.

Example 17

Laboratory vibratory ball mill to prepare iron-ferrous sulfide composite; (1) oxidation of 20% cavity volume Zirconium ball beads (particle size 10mm) were placed in a ball mill tank as grinding media; (2) 0.135g elemental sulfur powder and 2.365g zero-valent iron (particle size 38 microns to 74 microns) were weighed (the mass ratio of sulfur to iron was 1: 17.5) placed in a ball mill tank and filled with nitrogen in the tank; (3) Turn on the ball mill, adjust the grinding speed to 3000 times/min (about 3000 rpm), grind for 10 hours; (4) Use a sieve under a nitrogen atmosphere. The net separates the prepared granules from the grinding media to obtain a finished iron-sulfur sulphide composite.

Taking heavy metal cadmium as an example, the activity of the above materials was investigated. Add 3g of iron-iron sulfide complex in 300mL reagent bottle, fill it up with deionized water, cover with Teflon septum cover, then add cadmium ion stock solution to control the initial concentration of Cd(II) 50 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. The concentration of Cd(II) in the reagent bottle was monitored periodically. After 2 h of reaction, the concentration of Cd(II) was 3.88 mg L ^-1 , and the removal rate was 92.24%.

Example 18

The iron-sulfur sulphide composite is prepared by a planetary ball mill. The steps are as follows: (1) A zirconia ball-milling bead having a volume of 20% (0.6 mm in diameter) is placed in a ball mill tank as a grinding medium; (2) 0.256 g ferrous sulfide powder and 2.244g of zero-valent iron powder (particle size 38 microns ~ 74 microns) placed in a ball mill tank, and filled with nitrogen in the tank; (3) open the ball mill, adjust the grinding speed to 500 rpm, grinding for 5 hours (4) Separating the prepared iron-ferrous sulfide composite with a grinding medium under a nitrogen atmosphere to obtain a finished iron-sulfur sulfide composite.

Taking trichloroethylene as an example, the activity of the above materials was examined. Add 4.25g of iron-sulfur ferrous complex to the 425mL reagent bottle, top up with deionized water, cover with Teflon septum cover, then add trichloroethylene concentrate to control the initial trichloroethylene At a concentration of 10 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 5 h of reaction, the concentration of TCE decreased to 0.6 mg L ^-1 and the degradation rate was 94%.

Example 19

The iron-sulfur sulphide composite is prepared by a planetary ball mill. The steps are as follows: (1) A zirconia ball-milling bead having a volume of 20% (0.6 mm in diameter) is placed in a ball mill tank as a grinding medium; (2) 0.256 g pyrite powder and 2.244g of zero-valent iron powder (particle size 38μm ~ 74μm) are placed in the ball mill tank, and the tank is filled with nitrogen; (3) the ball mill is turned on, the grinding speed is adjusted to 500rpm, grinding for 5 hours (4) Separating the prepared iron-ferrous sulfide composite with a grinding medium under a nitrogen atmosphere to obtain a finished iron-sulfur sulfide composite.

Taking trichloroethylene as an example, the activity of the above materials was examined. Add 4.25g of iron-sulfur ferrous complex to the 425mL reagent bottle, top up with deionized water, cover with Teflon septum cover, then add trichloroethylene concentrate to control the initial trichloroethylene At a concentration of 10 mg L ^-1 , the reagent bottle was placed on a shaker and shaken. After 5 h of reaction, the concentration of TCE decreased to 1.2 mg L ^-1 and the degradation rate was 88%.

Claims

A method for preparing an iron-sulfur sulphide composite, characterized in that the method comprises: mixing elemental sulfur powder and micron-sized iron powder by a mass ratio of 1:5 to 60, and placing the obtained mixed raw material in a ball mill tank of a ball mill Inside, the ball mill tank is filled with grinding medium, the ball mill tank is in a vacuum environment or an inert gas atmosphere, the ball mill is turned on, the grinding speed is 400-4000 rpm, and the grinding is performed for 2 to 30 hours. After grinding, the grinding medium and the product are separated, and the iron is prepared. A ferrous sulfide composite.
The method of claim 1 wherein said ball mill is a planetary ball mill, a vibratory ball mill or a sand mill.
The method of claim 1 wherein said micron-sized iron powder is iron powder having a particle size of less than 100 microns.
The method according to claim 1, wherein said grinding medium is an iron ball, a steel ball, a silicon nitride ball or a zirconia ball having a diameter of 0.15 mm to 10 mm.
The method of claim 1 wherein said grinding medium is charged in an amount of from 10 to 50% by volume of the ball mill tank.
The method of claim 1 wherein said ball mill tank is an inert gas atmosphere.
The method according to claim 1, wherein the mass ratio of the elemental sulfur powder to the micron-sized iron powder is 1:9 to 18.
The method of claim 1 wherein said grinding is for a period of from 5 to 30 hours.
The method of claim 1 wherein said ball mill has a grinding speed of from 500 to 1000 rpm.
The method of claim 1 wherein said method is: elemental sulfur powder And the micron-sized iron powder is mixed at a mass ratio of 1:9-18, and the obtained mixed raw material is placed in a ball mill tank of a ball mill, and the ball mill tank is filled with 10 to 50% of a grinding medium volume, and the ball mill tank is an inert gas. The atmosphere, the ball mill is turned on, the grinding speed is 500-1000 rpm, and the grinding is performed for 5 to 30 hours. After the grinding, the grinding medium and the product are separated to obtain the iron-sulfur sulfide composite; the micron-sized iron powder has a particle diameter of less than 100 micrometers. The iron powder; the grinding medium is an iron ball, a steel ball, a silicon nitride ball or a zirconia ball having a diameter of 0.15 mm to 10 mm.
A method for preparing an iron-sulfur sulphide composite, characterized in that the method comprises: mixing iron sulfide powder or pyrite powder with micron-sized iron powder by a mass ratio of 1:5 to 60, and placing the obtained mixed raw material In the ball mill tank of the ball mill, the ball mill tank is filled with grinding medium. The ball mill tank is in a vacuum environment or an inert gas atmosphere. The ball mill is turned on, the grinding speed is 400-4000 rpm, and the grinding is performed for 2 to 30 hours. After grinding, the grinding medium and the product are separated. The iron-sulfur sulfide composite is obtained.
The method of claim 11 wherein said ball mill is a planetary ball mill, a vibratory ball mill or a sand mill.
The method of claim 1 wherein said micron-sized iron powder is iron powder having a particle size of less than 100 microns.
The method according to claim 11, wherein said grinding medium is an iron ball, a steel ball, a silicon nitride ball or a zirconia ball having a diameter of 0.15 mm to 10 mm.
The method of claim 11 wherein said grinding medium is charged in an amount of from 10 to 50% by volume of the ball mill tank.
The method of claim 11 wherein said ball mill tank is an inert gas atmosphere.
The method according to claim 11, wherein the mass ratio of the iron sulfide powder or pyrite powder to the micron-sized iron powder is 1:9-18.
The method of claim 11 wherein said grinding is for a period of from 5 to 30 hours.
The method of claim 11 wherein said ball mill has a grinding speed of from 500 to 1000 rpm.
The method according to claim 1, wherein the method comprises: mixing iron sulfide powder or pyrite powder with micron-sized iron powder at a mass ratio of 1:9-18, and placing the obtained mixed raw material in a ball mill ball mill. In the tank, the ball mill tank is filled with 10 to 50% of the grinding medium volume, the ball mill tank is inert gas atmosphere, the ball mill is turned on, the grinding speed is 500-1000 rpm, the grinding is 5-30 hours, and the grinding medium and the product are separated after grinding. That is, the iron-sulfur sulphide composite is prepared; the micron-sized iron powder is iron powder having a particle diameter of less than 100 micrometers; and the grinding medium is iron spheres, steel balls, silicon nitride having a diameter of 0.15 mm to 10 mm. Ball or zirconia ball.