CN103466644A - Method for preparing hydrophobic white carbon black - Google Patents

Abstract

The invention relates to a method for preparing hydrophobic white carbon black. The method comprises the steps of (a) weighing 1,000 parts by weight of sodium silicate solution with the concentration of 12-15%, adding 100-120 parts by weight of sodium sulfate into the sodium silicate solution, and uniformly stirring thoroughly so as to obtain mixed liquid; (b) adding 10-15% of sulfuric acid solution into the obtained mixed liquid, reacting until sodium silicate reaction is completed, and continuously stirring a reaction system at the rate of 1,200-1,500rpm while dropwise adding 0.1-0.2 part by weight of simethicone, so as to enable precipitates to appear in the reaction system. The method has the beneficial effects that through adding simethicone to coat silicon dioxide particles, the hydrophobicity of silicon dioxide is improved, the aggregation of the silicon dioxide particles is slowed down, the particle diameter of the white carbon black product is reduced, and the specific surface area is increased.

Description

A kind of preparation method of hydrophabic silica

Technical field:

The present invention relates to technical field prepared by the chemical field white carbon black, be specifically related to a kind of preparation method of hydrophabic silica.

Background technology:

White carbon black is lightweight hydrated SiO 2 material, with the micropore powder form of amorphous state, exists, and be a kind of purposes important Chemicals very widely.The white carbon black specific surface area is larger, usually be greater than 130m2/g, powder particle has a large amount of microvoid structures, the rich surface hydroxyl, the characteristics such as good absorption, fire-retardant, insulation, suspension, thixotropy, thixotroping, scattering of light, surface graft modification are arranged, and its remarkable strengthening action obtains important application at the rubber item manufacture field.

The precipitator method are divided into sulfuric acid process and salt acid system usually according to adopted sour kind difference, and wherein sulfuric acid process is the major way of production common white carbon black.

Water glass at first under hydrochloric acid or effect of sulfuric acid silicate ion wherein hydrolysis occurs obtains the silicic acid molecule, the silicic acid molecule continues dehydration again and obtains silicon dioxide molecules, silicon dioxide molecules and then rapidly polymerization obtain the silicon dioxide granule of polymeric form.In the preparation process of white carbon black, the size from collecting process and the polymerization degree of silicic acid molecule has determined the size of particles of white carbon black product, and more little more being easy to of product cut size disperseed.

Summary of the invention:

There are the problems such as the polymerization degree is too high, particle diameter large, specific surface is less, bad dispersibility in the present invention for the white carbon black that solves existing common precipitator method explained hereafter, avoid the sodium sulfate wastewater produced in the Production By Sulfuric Acid Process process to discharge the problem of environmental pollution caused simultaneously, the preparation method of hydrophabic silica is provided.

Technical solution of the present invention is as follows:

A kind of preparation method of hydrophabic silica, is characterized in that, comprises the following steps:

A, get sodium silicate solution 1000 weight parts that concentration is 12-15%, add in sodium silicate solution:

The sodium sulfate of 100-120 weight part, stir and obtain mixed solution;

B, in the mixed solution obtained, add the 10-15% sulphuric acid soln to react complete to water glass reaction, reaction system 1200-1500 rev/min is continued to stir, drip the dimethyl silicone oil of 0.1-0.2 weight part simultaneously, throw out appears in reaction system;

C, by the still aging 4-5h of the throw out obtained, then carry out press filtration, obtain filter cake;

The water that d, use are added with the 1-2% Sodium dodecylbenzene sulfonate carries out repetitive scrubbing, washes away dimethyl silicone oil, then, more repeatedly uses the clear water rinsing, drying, then through grinding the white carbon black of the loose property that secures satisfactory grades.

The invention has the beneficial effects as follows: in the present invention, by adding dimethyl silicone oil, the coated silica particle, increased the hydrophobicity of silicon-dioxide, and the polymerization of the silicon dioxide granule that slowed down has reduced the particle diameter of white carbon black product, has increased specific surface area.

Embodiment

A kind of preparation method of hydrophabic silica comprises the following steps:

A, get sodium silicate solution 1000 weight parts that concentration is 15%, add in sodium silicate solution:

The sodium sulfate of 120 weight parts, stir and obtain mixed solution;

B, in the mixed solution obtained, add 15% sulphuric acid soln to react complete to water glass reaction, reaction system 1200-1500 rev/min is continued to stir, drip the dimethyl silicone oil of 0.15 weight part simultaneously, throw out appears in reaction system;

C, by the still aging 4-5h of the throw out obtained, then carry out press filtration, obtain filter cake;

The water that d, use are added with 1% Sodium dodecylbenzene sulfonate carries out repetitive scrubbing, washes away dimethyl silicone oil, then, more repeatedly uses the clear water rinsing, drying, then through grinding the white carbon black of the loose property that secures satisfactory grades.

The BET specific surface area 332m of the white carbon black that after testing, prepared by the present invention ²/ g, the DPB absorption value reaches 3.3cm ³/ g.

Claims (1)

1. the preparation method of a hydrophabic silica, is characterized in that, comprises the following steps:

A, get sodium silicate solution 1000 weight parts that concentration is 12-15%, add in sodium silicate solution:

The sodium sulfate of 100-120 weight part, stir and obtain mixed solution;

B, in the mixed solution obtained, add the 10-15% sulphuric acid soln to react complete to water glass reaction, reaction system 1200-1500 rev/min is continued to stir, drip the dimethyl silicone oil of 0.1-0.2 weight part simultaneously, throw out appears in reaction system;

C, by the still aging 4-5h of the throw out obtained, then carry out press filtration, obtain filter cake;

The water that d, use are added with the 1-2% Sodium dodecylbenzene sulfonate carries out repetitive scrubbing, washes away dimethyl silicone oil, then, more repeatedly uses the clear water rinsing, drying, then through grinding the white carbon black of the loose property that secures satisfactory grades.