CN100377997C - Method for extracting nano silicon dioxide from calcium-base bentonite - Google Patents

Abstract

The present invention discloses a method for extracting nanometer silicon dioxide from calcium bentonite, which comprises the steps as follows: calcium bentonite is matched into water slurry, added with a cationic surface active agent as an intercalation agent for layer expansion, and added with concentrated sulfuric acid for ion exchange; after the reaction, an anion surface active agent or a non-ionic surface active agent is adopted for preventing the aggregation of particles, and the mixed solution is repeatedly pressed and filtered, and centrifugally spray dried in the end. The nanometer silicon dioxide product prepared with the present invention has high product quality and contains about 95% of silicon dioxide. The particle size of nanometer silicon dioxide is from 20 to 90 nanometers, more than 80% of the particle size is 50 nanometers, and the nanometer silicon dioxide shapes approximately to a ball. The present invention has simple equipment and low production cost which is approximately 20% of that of the traditional method for preparing silicon dioxide.

Description

From calcium-base bentonite, extract the method for nano silicon

Technical field

The invention belongs to a kind of extraction process of nano silicon, specifically is a kind of method of extracting nano silicon from calcium-base bentonite.

Background technology

Along with the development of Chinese national economy, the nanometer titanium dioxide silicon materials are extensively paid attention to and are used, and domestic annual usage quantity increases considerably.Nearly 2 years, the nano silica powder field of using was expanded rapidly, now has been applied to tens fields.Because traditional fabrication method cost height, the equipment price costliness causes nano silica powder material market price height, thereby has restricted the application of nano material.

China's calcium-base bentonite reserves are very big, use also very extensively, but have not yet to see the report that is used to extract silicon-dioxide.

Summary of the invention

The purpose of this invention is to provide a kind of method of from calcium-base bentonite, extracting nano silicon, can reduce the production cost of nano silicon greatly, and the quality product height.

Technical scheme of the present invention is as follows:

From calcium-base bentonite, extract the method for nano silicon, it is characterized in that may further comprise the steps successively:

(1), calcium-base bentonite is soaked in water, and removes impurity;

(2), preparation calcium-base bentonite aqueous slurry, wherein the calcium-base bentonite solid content is 20-60%;

(3), add cats product as intercalator, reaction times: 2-4 hour, temperature: 80-130 ℃;

(4), add 98% vitriol oil by the 10-30% volume ratio and carry out ion exchange reaction, temperature of reaction 80-130 ℃, time 2-4 hour;

(5), adding negatively charged ion or nonionogenic tenside, to add weight be the 0.05%-1% of solid content, and silicon dioxide microparticle is carried out surface protection, stops silicon dioxide microparticle to be reunited;

(6), press filtration obtains silicon-dioxide;

(7), repeat above (2)-(6) step, two to three times;

(8), silicon-dioxide is made into the aqueous solution after the press filtration, and making beating, adding negatively charged ion or nonionogenic tenside again, to add weight be the 0.05%-1% of solid content, and silicon dioxide microparticle is carried out surface protection, stops silicon dioxide microparticle to be reunited;

(9), centrifugal spray drying, promptly get nano silicon.

Described cats product is a quaternary ammonium salt cationic surfactant, and anion surfactant is the sulfonate type anion surfactant, and nonionogenic tenside is an alkylphenol polyoxyethylene type nonionogenic tenside.

Compare with prior art, the present invention extracts nano silicon quality height, and dioxide-containing silica about 95% in its product, silicon-dioxide particle diameter 20-90 nanometer, 50 nanometers account for more than 80% the form almost spherical.Its production cost is about 20% of traditional silicon dioxide production cost.

Embodiment

From calcium-base bentonite, extract the method for nano silicon, may further comprise the steps successively:

(1), calcium-base bentonite is soaked in water, and removes impurity;

(2), preparation calcium-base bentonite aqueous slurry, wherein the calcium-base bentonite solid content is 20-60%;

3), add cats product as intercalator, reaction times: 2-4 hour, temperature: 80-130 ℃;

(4), add 98% vitriol oil by the 10-30% volume ratio and carry out ion exchange reaction, temperature of reaction 80-130 ℃, time 2-4 hour;

(5), adding negatively charged ion or nonionogenic tenside, to add weight be the 0.05%-1% of solid content, and silicon dioxide microparticle is carried out surface protection, stops silicon dioxide microparticle to be reunited;

(6), press filtration obtains silicon-dioxide;

(7), repeat above (2)-(6) step, two to three times;

(8), silicon-dioxide is made into the aqueous solution after the press filtration, through the hollander making beating, adding negatively charged ion or nonionogenic tenside again, to add weight be the 0.05%-1% of solid content, and silicon dioxide microparticle is carried out surface protection, stops silicon dioxide microparticle to be reunited;

(9), centrifugal spray drying, promptly get nano silicon.

Cats product is a quaternary ammonium salt cationic surfactant, and anion surfactant is the sulfonate type anion surfactant, and nonionogenic tenside is an alkylphenol polyoxyethylene type nonionogenic tenside.

Above-described each parameter all can be implemented in its interval range.

Claims (1)

1. from calcium-base bentonite, extract the method for nano silicon, it is characterized in that may further comprise the steps successively:

(1), calcium-base bentonite is soaked in water, and removes impurity;

(2), preparation calcium-base bentonite aqueous slurry, wherein the calcium-base bentonite solid content is 20-60%;

(3), add cats product as intercalator, reaction times: 2-4 hour, temperature: 80-130 ℃;

(4), add 98% vitriol oil by the 10-30% volume ratio and carry out ion exchange reaction, temperature of reaction 80-130 ℃, time 2-4 hour;

(5), adding negatively charged ion or nonionogenic tenside, to add weight be the 0.05%-1% of solid content, and silicon dioxide microparticle is carried out surface protection, stops silicon dioxide microparticle to be reunited;

(6), press filtration obtains silicon-dioxide;

(7), repeat above (2)-(6) step, two to three times;

(8), silicon-dioxide is made into the aqueous solution after the press filtration, and making beating, adding negatively charged ion or nonionogenic tenside again, to add weight be the 0.05%-1% of solid content, and silicon dioxide microparticle is carried out surface protection, stops silicon dioxide microparticle to be reunited;

(9), centrifugal spray drying, promptly get nano silicon;

Described cats product is a quaternary ammonium salt cationic surfactant, and anion surfactant is the sulfonate type anion surfactant, and nonionogenic tenside is an alkylphenol polyoxyethylene type nonionogenic tenside.