CN104001934A - Preparing method for dispersing nanometer iron particles - Google Patents

Abstract

The invention provides a preparing method for dispersing nanometer iron particles and relates to a preparing method for nanometer metal particles. According to the preparing method, a certain dispersing agent is added, a liquid phase chemical reduction method is adopted for dissolving soluble ferrous iron or ferric iron salt in distilled water or mixed liquid of the distilled water and alcohol to form iron salt solution, and then a reducing agent like hydroboron with the strong reducing property is adopted for directly reducing iron ions into zero-valent iron. Vacuum drying is carried out on a product after the product is filtered and washed, and therefore a dusty nano-meter iron material which is provided with a nanometer microstructure and has the good dispersing performance is obtained. The nanometer iron particles prepared through the method are spherical, the grain size is small, the particle size range is small, and the particles have resistance to oxidation; the nanometer iron particles produced through the method have good dispersing performance, and the problem that the nanometer iron particles accumulate easily can be effectively solved; the purity of the product is high, the grain size is small and uniform, the process is simple and easy to control as the process is carried out at the normal temperature, and the actual requirement of production can be met.

Description

A kind of preparation method of dispersed nano-iron particles

technical field

The present invention relates to a preparation method of nano-metal particles, in particular to a preparation method of dispersed nano-iron particles.

Background technique

Powders or materials with a particle size in the range of 1 to 100 nanometers (nm) are usually called nanomaterials. Nanomaterials are widely used in various fields because of their unique properties. Because of its transition region between macroscopic conventional fine powder and microscopic atomic clusters, nano-iron exhibits some unique properties, one of which is the surface effect. Due to its small particle size, large specific surface area, and strong surface activity, nano-iron has more unique advantages than ordinary iron powder in the remediation of pollutants. Many foreign studies have shown that nano-iron can reduce and remove many pollutants in water, such as dissolved organic chlorides, PCBs and nitrobenzene compounds.

Due to the small particle size, strong activity, easy coalescence, and easy oxidation of nano-iron, it is often used on the spot and must be isolated from oxygen during preparation and use. It is inconvenient to use and high in cost. Therefore, it is limited in practical applications. , the commonly used preparation methods are physical method and chemical method. Some methods are feasible in theory, but the actual operating conditions are very demanding and not easy to implement.

Contents of the invention

The purpose of the present invention is to provide a method for preparing dispersed nano-iron particles. This method uses a solvent to directly add a dispersant in the liquid state reduction process, effectively preventing the agglomeration of nano-iron particles, uniform dispersion, narrow particle size range, and good practical application. Effect, and the process is simple, low cost, easy to further expand the scale of production.

The purpose of the present invention is achieved through the following technical solutions:

A method for preparing dispersed nano-iron particles, the method comprising the following preparation process:

(1) Using soluble ferrous iron or ferric salt as raw material, use distilled water or a mixed solution of distilled water and ethanol with a volume ratio of 7:3 to prepare the solution so that the concentration of iron ions in it reaches 0.2-2mol/L;

(2) Add surfactant to (1) to make the concentration reach 0.2-0.4g/L, add complexing agent to make the concentration reach 0.002-0.005g/L;

(3) Add dispersant to (2) so that its volume ratio reaches 2/5000;

(4) Configure borohydride aqueous solution so that its concentration is 0.02-0.1mol/L;

(5) When the solution obtained in (3) is in a stirring state, drop the solution (4) into it, the dropping speed is 1-10ml/s, the temperature of the reaction process is room temperature, add the solution (4) dropwise until the reaction is complete;

(6) After the process in (5) ends, the reaction product obtained is subjected to suction filtration, and washed several times with distilled water and absolute ethanol;

(7) (6) The obtained product is vacuum-dried at 60° C. for 10-24 hours to obtain black dispersed nano-iron particles.

In the method for preparing dispersed nano-iron particles, the ferrous salt is ferrous chloride, and the ferric salt is ferric sulfate or ferric chloride.

In the method for preparing dispersed nano-iron particles, the surfactant is soluble starch.

In the method for preparing dispersed iron nanoparticles, the complexing agent is citric acid.

In the preparation method of dispersed nano-iron particles, the dispersant is TH-904, that is, a water-based dispersant whose main component is anionic polymer.

In the method for preparing dispersed nano-iron particles, the reducing agent is sodium borohydride or potassium borohydride.

Advantage and effect of the present invention are:

1. The synthesized nano-iron particle material has good dispersion performance, effectively solving the problem of nano-iron particle agglomeration; and the product has high purity, small particle size, uniform particle size, and certain oxidation resistance;

2. The synthetic route is simple and the process control is easy;

3. The production and preparation process is carried out under normal temperature and pressure, which meets the actual needs of production.

Detailed ways

Below in conjunction with embodiment, the present invention is described in further detail.

Example 1

Prepare dispersed nano-iron particles, the preparation steps are:

(1) Weigh ferric chloride, dissolve it in distilled water, and make a solution with an iron ion concentration of 0.8 mol/liter;

(2) Add surfactant soluble starch to the solution obtained in (1) to make the concentration reach 0.4 g/L, add complexing agent citric acid to make the concentration reach 0.004 g/L;

(3) Dilute the TH-904 stock solution 100 times and add it to the solution obtained in (2), so that the TH-904 content is 1:2500 (volume ratio).

(4) Weigh sodium borohydride and dissolve it in distilled water to prepare a solution with a sodium borohydride content of 0.02 mol/liter;

(5) When the solution obtained in (3) is in a stirring state, drop the solution (4) into the reduction reaction at a rate of 5 ml/s, and control the temperature at 20 degrees Celsius during the reaction until the reaction is complete;

(6) After the reaction in (5), the solid product obtained by the reaction was suction filtered, and the product was rinsed three times with distilled water and three times with absolute ethanol;

(7) The product obtained in (6) was vacuum-dried at 60 degrees Celsius for 10 hours to obtain black uniformly dispersed nano-iron particles.

Example 2

Prepare dispersed nano-iron particles, the preparation steps are:

(1) Weigh ferric sulfate, dissolve it in a mixed solution of distilled water and absolute ethanol (volume ratio = 7:3), and make a solution with an iron ion concentration of 0.2 mol/liter;

(2) add surfactant soluble starch in the solution gained in (1), make its concentration reach 0.2 gram/liter, add complexing agent citric acid, make its concentration reach 0.002 gram/liter;

(3) Dilute the TH-904 stock solution 100 times and add it to the solution obtained in (2), so that the TH-904 content is 1:2500 (volume ratio).

(4) Take sodium borohydride and dissolve it in distilled water to form a solution with a sodium borohydride content of 0.02 mol/liter;

(5) When the solution obtained in (3) is in a stirring state, drop the solution (4) to carry out the reduction reaction, the dropping rate is 10 ml/s, and the temperature is controlled at 20 degrees Celsius during the reaction until the reaction is complete;

(6) After the reaction in (5), the solid product obtained by the reaction was suction filtered, and the product was rinsed three times with distilled water and three times with absolute ethanol;

(7) Vacuum-dry the product obtained in (6) at 60 degrees Celsius for 24 hours to obtain black uniformly dispersed nano-iron particles.

Example 3

Prepare dispersed nano-iron particles, the preparation steps are:

(1) take ferrous chloride, be dissolved in distilled water, be made into the solution that iron ion concentration is 1.6 mol/liter;

(2) add surfactant soluble starch in the solution gained in (1), make its concentration reach 0.4 gram/liter, add complexing agent citric acid, make its concentration reach 0.004 gram/liter;

(3) Dilute the TH-904 stock solution 100 times and add it to the solution obtained in (2), so that the TH-904 content is 1:2500 (volume ratio).

(4) Potassium borohydride is weighed and dissolved in distilled water to form a solution with a potassium borohydride content of 0.02 mol/liter;

(5) When the solution obtained in (3) is in a stirring state, drop the solution (4) to carry out the reduction reaction, the dropping rate is 5 ml/s, and the temperature is controlled at 20 degrees Celsius during the reaction until the reaction is complete;

(6) After the reaction in (5), the solid product obtained by the reaction was suction filtered, and the product was rinsed three times with distilled water and three times with absolute ethanol;

(7) Vacuum-dry the product obtained in (6) at 60 degrees Celsius for 24 hours to obtain black uniformly dispersed nano-iron particles.

Claims (6)

1. a method for preparing dispersed nano-iron particles, characterized in that, the method comprises the following preparation process: (1) Using soluble ferrous iron or ferric salt as raw material, use distilled water or a mixed solution of distilled water and ethanol with a volume ratio of 7:3 to prepare the solution so that the concentration of iron ions in it reaches 0.2-2mol/L; (2) Add surfactant to (1) to make the concentration reach 0.2-0.4g/L, add complexing agent to make the concentration reach 0.002-0.005g/L; (3) Add dispersant to (2) to make its volume ratio reach 2/5000; (4) Prepare borohydride aqueous solution so that its concentration is 0.02-0.1mol/L; (5) When the solution obtained in (3) is in a stirring state, drop the solution (4) into it, the dropping speed is 1-10ml/s, the temperature of the reaction process is room temperature, drop the solution (4) until the reaction is complete; (6) After the process of (5) is finished, the obtained reaction product is subjected to suction filtration, and washed with distilled water and absolute ethanol for several times; (7) The product obtained in (6) is vacuum-dried at 60° C. for 10-24 hours to obtain black dispersed nano-iron particles. 2. A method for preparing dispersed nano-iron particles according to claim 1, wherein the ferrous salt is ferrous chloride, and the ferric salt is ferric sulfate or ferric chloride. 3. A method for preparing dispersed nano-iron particles according to claim 1, wherein the surfactant is soluble starch. 4. A method for preparing dispersed nano-iron particles according to claim 1, wherein the complexing agent is citric acid. 5 . The method for preparing dispersed nano-iron particles according to claim 1 , wherein the dispersant is TH-904, a water-based dispersant whose main component is an anionic polymer. 6 . The method for preparing dispersed nano-iron particles according to claim 1 , wherein the reducing agent is sodium borohydride or potassium borohydride.