Micron-sized molecular sieve supported nano-iron material preparation method

Abstract

The invention provides a micron-sized molecular sieve supported nano-iron material preparation method. The method comprises a step of molecular sieve support pretreatment and a step of preparation of a molecular sieve supported nano-iron material. An MCM-41 meso-porous molecular sieve is treated as a support, nano-iron particles are generated on the molecular sieve support in an in situ mode through a liquid phase reduction process, the nano-iron mass loading rate of the molecular sieve supported nano-iron material is 25-90%, and the prepared molecular sieve supported nano-iron material has a particle size range of 1.2-20mum and an aperture range of 1.5-4.5nm. The MCM-41 meso-porous molecular sieve is coupled with nano-iron to prepare the high-activity micron-sized supported nano-iron material. The method has the advantages of effective improvement of the stability of the nano-iron in air, increase of the dispersibility of the nano-iron in an aqueous medium, effective inhibition of the agglomeration effect of nano-iron particles, increase of the active sites of the nano-iron material, and increase of the surface activity of the nano-iron material, and allows the nano-iron material to be easy separated and recovered in the water treatment technology and the recovery rate to reach 100%.

Description

technical field

[0001] The invention relates to inorganic functional materials and fine chemical preparation technology, in particular to a preparation method of micron molecular sieve-loaded nano-iron material. Background technique

[0002] With the maturity of nanotechnology, a large number of nanomaterials have been invented, prepared and used. It is precisely because nanomaterials have excellent physical and chemical characteristics, such as quantum size effect, surface effect and quantum tunneling effect. These characteristics are applied in the process of environmental protection and water body restoration, and some traditional materials will not be able to replace them, which makes nanomaterials more widely used.

[0003] As an emerging environmental remediation engineering material, nano-iron is mainly used in the remediation of soil and groundwater. Nano-iron has important characteristics that ordinary zero-valent iron does not have, such as: large specific surfac...

Examples

preparation example Construction

[0026] The preparation method of micron grade molecular sieve loaded nano-iron material of the present invention, the method comprises the following steps:

[0027] (1) Activation pretreatment of molecular sieve carrier

[0028] MCM-41 mesoporous molecular sieve is used as the carrier of micron-sized molecular sieve-loaded nano-iron material, and the carrier is activated and pretreated by heat treatment activation method and acid activation method;

[0029] Heat treatment activation method: the carrier is placed in a muffle furnace, and the carrier is heat-treated to activate the carrier by a stepwise heating and holding method. The activation steps are: heating to 200°C-250°C within 1h-2h, and constant temperature for 1h-2h; Then raise the temperature to 350°C-400°C within 1h-2h, keep the temperature constant for 1h-2h; finally raise the temperature to 550°C-600°C within 1h-2h, keep the temperature constant for 4h-6h;

[0030] Acid activation method: place the carrier activa...

Embodiment 1

[0041] Example 1 Preparation of nano-iron material with a nano-sized molecular sieve-loaded nano-iron material with a mass loading of 25%

[0042] 100ml0.2mol / L FeSO 4 ·7H 2 O can be reduced to produce 1.1g nano-iron

[0043] The mass of the added MCM-41 carrier was 3.0 g.

[0044] The mass loading of nano-iron (%)=1.1g / (1.1g+3.0)×100%=25%.

[0045] Using liquid phase reduction method: for FeSO 4 The ethanol-water solution system, using drop-strengthening reducing agent NaBH 4 to Fe 2+ Reduction is carried out to obtain nano-iron particles.

[0046] At a temperature of 15°C-35°C, mix 3.0g of activated MCM-41 mesoporous molecular sieve with 100ml of 0.2mol / L FeSO 4 ·7H 2 O aqueous solution is placed in a three-necked flask, sealed, and recorded as component A; component A is placed on a magnetic stirrer, nitrogen protection is passed into the three-necked flask, and component A is ultrasonically dispersed for 10 minutes, and magnetic stirring is turned on to make the co...

Embodiment 2

[0049] Example 2 Preparation of nanometer-sized molecular sieve-loaded nano-iron material with a mass loading of nano-iron of 35%

[0050] 100ml0.2mol / L FeSO 4 ·7H 2 O can be reduced to produce 1.1g nano-iron

[0051] The mass of the added MCM-41 carrier was 2.0 g.

[0052] The mass loading of nano-iron (%)=1.1g / (1.1g+2.0)×100%=35%.

[0053] Using liquid phase reduction method: for FeSO 4 The ethanol-water solution system, using drop-strengthening reducing agent KBH 4 to Fe 2+ Reduction is carried out to obtain nano-iron particles.

[0054] At a temperature of 15°C-35°C, mix 2.0g of activated MCM-41 mesoporous molecular sieve with 100ml of 0.2mol / L FeSO 4 ·7H 2 O aqueous solution is placed in a three-necked flask, sealed, and recorded as component A; component A is placed on a magnetic stirrer, nitrogen protection is passed into the three-necked flask, and component A is ultrasonically dispersed for 10 minutes, and magnetic stirring is turned on to make the component A...

technical field

[0001] The invention relates to inorganic functional materials and fine chemical preparation technology, in particular to a preparation method of micron molecular sieve-loaded nano-iron material. Background technique

[0002] With the maturity of nanotechnology, a large number of nanomaterials have been invented, prepared and used. It is precisely because nanomaterials have excellent physical and chemical characteristics, such as quantum size effect, surface effect and quantum tunneling effect. These characteristics are applied in the process of environmental protection and water body restoration, and some traditional materials will not be able to replace them, which makes nanomaterials more widely used.

[0003] As an emerging environmental remediation engineering material, nano-iron is mainly used in the remediation of soil and groundwater. Nano-iron has important characteristics that ordinary zero-valent iron does not have, such as: large specific surfac...

Examples

preparation example Construction

[0026] The preparation method of micron grade molecular sieve loaded nano-iron material of the present invention, the method comprises the following steps:

[0027] (1) Activation pretreatment of molecular sieve carrier

[0028] MCM-41 mesoporous molecular sieve is used as the carrier of micron-sized molecular sieve-loaded nano-iron material, and the carrier is activated and pretreated by heat treatment activation method and acid activation method;

[0029] Heat treatment activation method: the carrier is placed in a muffle furnace, and the carrier is heat-treated to activate the carrier by a stepwise heating and holding method. The activation steps are: heating to 200°C-250°C within 1h-2h, and constant temperature for 1h-2h; Then raise the temperature to 350°C-400°C within 1h-2h, keep the temperature constant for 1h-2h; finally raise the temperature to 550°C-600°C within 1h-2h, keep the temperature constant for 4h-6h;

[0030] Acid activation method: place the carrier activa...

Embodiment 1

[0041] Example 1 Preparation of nano-iron material with a nano-sized molecular sieve-loaded nano-iron material with a mass loading of 25%

[0042] 100ml0.2mol / L FeSO 4 ·7H 2 O can be reduced to produce 1.1g nano-iron

[0043] The mass of the added MCM-41 carrier was 3.0 g.

[0044] The mass loading of nano-iron (%)=1.1g / (1.1g+3.0)×100%=25%.

[0045] Using liquid phase reduction method: for FeSO 4 The ethanol-water solution system, using drop-strengthening reducing agent NaBH 4 to Fe 2+ Reduction is carried out to obtain nano-iron particles.

[0046] At a temperature of 15°C-35°C, mix 3.0g of activated MCM-41 mesoporous molecular sieve with 100ml of 0.2mol / L FeSO 4 ·7H 2 O aqueous solution is placed in a three-necked flask, sealed, and recorded as component A; component A is placed on a magnetic stirrer, nitrogen protection is passed into the three-necked flask, and component A is ultrasonically dispersed for 10 minutes, and magnetic stirring is turned on to make the co...

Embodiment 2

[0049] Example 2 Preparation of nanometer-sized molecular sieve-loaded nano-iron material with a mass loading of nano-iron of 35%

[0050] 100ml0.2mol / L FeSO 4 ·7H 2 O can be reduced to produce 1.1g nano-iron

[0051] The mass of the added MCM-41 carrier was 2.0 g.

[0052] The mass loading of nano-iron (%)=1.1g / (1.1g+2.0)×100%=35%.

[0053] Using liquid phase reduction method: for FeSO 4 The ethanol-water solution system, using drop-strengthening reducing agent KBH 4 to Fe 2+ Reduction is carried out to obtain nano-iron particles.

[0054] At a temperature of 15°C-35°C, mix 2.0g of activated MCM-41 mesoporous molecular sieve with 100ml of 0.2mol / L FeSO 4 ·7H 2 O aqueous solution is placed in a three-necked flask, sealed, and recorded as component A; component A is placed on a magnetic stirrer, nitrogen protection is passed into the three-necked flask, and component A is ultrasonically dispersed for 10 minutes, and magnetic stirring is turned on to make the component A...

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