Micro-pore silicon carbide fiber and preparing method thereof

Abstract

The invention relates to micropore carbofrax fiber and a process for preparation. Micropore carbofrax fiber is characterized in that the content of Si is 40-65 wt%, the content of C is 25-45 wt%, residual material is O, micropore carbofrax fiber takes continuous fibrous shape, the volume of micropore (pore diameter <= 2nm) accounts for more than 85 vol% of total pore volume, average pore size is 1.30-2.00nm, and specific surface area is 1100-2100m 2 / g. The process for preparation is characterized in that carbofrax fiber which is rich with C is firstly prepared by blending mixing, non-melting and cracking through poly carbon silicon alky and carbonaceous high polymer, then micropore carbofrax fiber is obtained through activating carbon removing technology. The volume of micropore of micropore carbofrax fiber of the invention has high content, and pore diameter is stable and hard to collapse, and has high specific surface area, high thermally insulating property and good oxidation resistance property, and the invention has good application prospect in the field of environmental control, energy storage, medical health and the like.

Description

Technical field

[0001] The invention relates to a microporous material and a preparation method thereof, in particular to a microporous silicon carbide fiber and a preparation method thereof. Background technique

[0002] Macroporous and mesoporous materials are mainly used as catalyst carriers, filtering macromolecular substances, and heat insulation, heat preservation, sound insulation materials, etc., while microporous materials are mostly used in the fields of adsorption and separation of small molecular substances and energy storage. Microporous materials are The research hotspots in recent years have been placed high hopes in the fields of environmental governance, medicine and health, and energy storage.

[0003] Inorganic non-metallic microporous materials have become the focus of research due to their good stability, temperature resistance and corrosion resistance. Among them, the most researched microporous materials are mainly carbon materials, such as super activated ...

Examples

Embodiment 1

[0025] The Si content of the microporous silicon carbide fiber in this embodiment is 55wt%, the C content is 31wt%, and the O content is 14wt%. It is in the form of continuous fibers. The microscopic morphology is shown in Figure 1, and the fiber pore size distribution is shown in Figure 2. , The volume of the micropores (pore size≤2nm, the same below) accounts for 95vol% of the total pore volume, the specific surface area is 2085m2 / g, and the average pore size is 1.72nm.

[0026] Preparation: Take 10g of PCS and 16g of phenolic with a softening point of 180-190℃ to dissolve in tetrahydrofuran, stir and mix uniformly, distill off the solvent under the protection of high-purity nitrogen with a purity of ≥99%, and place the blend precursor in In the melt spinning device, under the protection of high-purity nitrogen with a purity of ≥99%, it is heated to 330°C and defoamed, and then melt-spinning is performed at 280°C, 0.5MPa and 100m / min at a speed of 100m / min to obtain raw yarn ; P...

Embodiment 2

[0028] The Si content of the microporous silicon carbide fiber in this embodiment is 63wt%, the C content is 24wt%, and the O content is 13wt%. It is in the form of continuous fibers. The micropore volume accounts for 88vol% of the total pore volume, and the specific surface area is 1200m. 2 / g, the average pore diameter is 1.25nm.

[0029] Preparation: The only difference from Example 1 is that the raw materials are blended with 10g PCS and 3g phenolic with a softening point of 180-190°C.

Embodiment 3

[0031] The Si content of the microporous silicon carbide fiber of this embodiment is 48wt%, the C content is 38wt%, and the O content is 14wt%. It is in the form of continuous fibers. The micropore volume accounts for 89vol% of the total pore volume, and the specific surface area is 1609m. 2 / g, the average pore size is 1.95nm.

[0032] Preparation: The only difference from Example 1 is that the raw materials are blended with 10 g of PCS and 25 g of phenolic with a softening point of 180-190°C.

Technical field

[0001] The invention relates to a microporous material and a preparation method thereof, in particular to a microporous silicon carbide fiber and a preparation method thereof. Background technique

[0002] Macroporous and mesoporous materials are mainly used as catalyst carriers, filtering macromolecular substances, and heat insulation, heat preservation, sound insulation materials, etc., while microporous materials are mostly used in the fields of adsorption and separation of small molecular substances and energy storage. Microporous materials are The research hotspots in recent years have been placed high hopes in the fields of environmental governance, medicine and health, and energy storage.

[0003] Inorganic non-metallic microporous materials have become the focus of research due to their good stability, temperature resistance and corrosion resistance. Among them, the most researched microporous materials are mainly carbon materials, such as super activated ...

Examples

Embodiment 1

[0025] The Si content of the microporous silicon carbide fiber in this embodiment is 55wt%, the C content is 31wt%, and the O content is 14wt%. It is in the form of continuous fibers. The microscopic morphology is shown in Figure 1, and the fiber pore size distribution is shown in Figure 2. , The volume of the micropores (pore size≤2nm, the same below) accounts for 95vol% of the total pore volume, the specific surface area is 2085m2 / g, and the average pore size is 1.72nm.

[0026] Preparation: Take 10g of PCS and 16g of phenolic with a softening point of 180-190℃ to dissolve in tetrahydrofuran, stir and mix uniformly, distill off the solvent under the protection of high-purity nitrogen with a purity of ≥99%, and place the blend precursor in In the melt spinning device, under the protection of high-purity nitrogen with a purity of ≥99%, it is heated to 330°C and defoamed, and then melt-spinning is performed at 280°C, 0.5MPa and 100m / min at a speed of 100m / min to obtain raw yarn ; P...

Embodiment 2

[0028] The Si content of the microporous silicon carbide fiber in this embodiment is 63wt%, the C content is 24wt%, and the O content is 13wt%. It is in the form of continuous fibers. The micropore volume accounts for 88vol% of the total pore volume, and the specific surface area is 1200m. 2 / g, the average pore diameter is 1.25nm.

[0029] Preparation: The only difference from Example 1 is that the raw materials are blended with 10g PCS and 3g phenolic with a softening point of 180-190°C.

Embodiment 3

[0031] The Si content of the microporous silicon carbide fiber of this embodiment is 48wt%, the C content is 38wt%, and the O content is 14wt%. It is in the form of continuous fibers. The micropore volume accounts for 89vol% of the total pore volume, and the specific surface area is 1609m. 2 / g, the average pore size is 1.95nm.

[0032] Preparation: The only difference from Example 1 is that the raw materials are blended with 10 g of PCS and 25 g of phenolic with a softening point of 180-190°C.

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