CN1123807A - Method for producing white carbon black from husk of rice - Google Patents

Abstract

The method for producing white carbon black using rice husk includes such steps as removing impurities, treating with inorganic acid solution to remove metallic impurities and bioligand, washing with treated water to remove hydrogen ion, metallic impurities and bioligand from the surface of rice husk and burning.

Description

Method with producing white carbon black from husk of rice

The present invention relates to method with producing white carbon black from husk of rice.

White carbon black has purposes widely in industrial aspect, can be used as the filler of rubber plastic, improves intensity, tear strength, sliding resistance, the grease proofness of rubber plastic, and particularly manufacturing is white, colored, the light-colour rubber plastics are more suitable; Can be used as the additive of paint, building materials, daily-use chemical industry, medicine, agricultural chemicals etc.; In paper industry, can be used as the top layer filler of weighting agent and paper, or the like.

At present, the production method for white carbon black of comparative maturity is the dry method (combustion method) and the precipitator method.Dry method is through pyrohydrolysis or high temperature oxidation and get with silicoorganic compound (as silicon tetrachloride, methyl chlorosilane etc.).The precipitator method are to be raw material with the water glass, with acid and water glass effect, get the mass consumption industrial chemicals and the energy, cost height, complex process through rinsing, drying, calcining.

Recent study finds that it is very high to contain silica volume in the agricultural wastes such as husk, straw, as dioxide-containing silica in the rice husk about 15%.At present, these raw materials obtain certain utilization at the energy, building materials (as the rice husk composition board), building aspects such as (as cement), but utilization ratio is lower.

Raw material sources such as husk are abundant, and cheap and easy to get, people are devoted to develop its silicon source always, and as Chinese patent 86107192 and 86104705 (application number), its invention is done a lot of work at aspects such as production technique and product structures per capita.But from the cell tissue configuration aspects, in cell life movement whole process, the always continuous and environment exchange inorganic substance of cell, certainly existing a large amount of inorganic substance in these raw materials, in with these raw material production white carbon black processes, how removing metallic impurity becomes an important ring, because the existence of metallics, dialogue sooty application influence is very big.Last patent (86107192) does not consider how to remove metallic impurity; Back one patent (86104705) is though considered the removal metallic impurity, but on technology, be worth discussing, metallic impurity in these raw materials are under the situation of high-temp combustion, all do not exist with pure simple oxide form, but form mixture with silicon-dioxide in large quantities, go to handle with dilute hydrochloric acid and dilute sulphuric acid, can not decompose these mixtures in a large number to reach the purpose of removing metallic impurity.The existence of metallic impurity and silica composite makes the white carbon black outward appearance can not become pure white, but also influences the perfect combustion of raw material, and in retort furnace, constant temperature (600 ℃) is difficult to perfect combustion.

In the moiety of husk, except that Mierocrystalline cellulose, hemicellulose, xylogen, silicon-dioxide, also exist materials such as protein, lipid, these materials are the metallic impurity factor of relying and existing just, metallic impurity exist with the bio-ligand form, as conjugated protein, metalloporphyrin, chloroplast(id), pigment or the like.

The objective of the invention is to destroy the structure of above-mentioned bio-ligand, bio-ligand or metallic impurity can be disintegrated down from raw material, produce the white carbon black that color and luster is white, purity is high.

For achieving the above object, production technique of the present invention comprises following step:

A, at first husk is carried out purifying treatment, available air blast process or sieve method are removed foreign material such as shrivelled kernel and earth in the husk;

B, then husk is removed metallic impurity and bio-ligand and handle, in temperature is under the condition of 0 ℃ of-250 ℃ of scope, in encloses container, be that inorganic acid solution more than 1% is handled husk with hydrogen ion concentration, by agitation and hydrionic effect, metallic impurity or bio-ligand are disintegrated down from husk;

C, then water cleaning are taken out husk from acidic solution, with treated water, clean hydrogen ion, metallic impurity and the bio-ligand on husk surface as distilled water, ion exchanged water, high purity water etc., and drain, and be stand-by;

D, postheating burning husk, begin from indirect heating, make the husk moisture evaporation, and reach its point of ignition, utilize the heat energy of husk own, carry out the albefaction burning, make organic substance and charcoal perfect combustion, temperature is controlled at more than 350 ℃, needs in the combustion processes to ventilate, be supplemental oxygen, and discharge products of combustion;

E, at last product is pulverized, the white carbon black form after the burning is the form that silicon-dioxide exists in husk, can require to pulverize according to user's particle diameter get product, then packing.

The invention has the advantages that on production craft step, the step that will remove metallic impurity and bio-ligand to raw material is by coming before the burning, so both improved the effect of removing metallic impurity greatly, the quality of product is improved greatly, and help burning, only need several hours combustion time.

Provide specific embodiment of the present invention below, this example carries out in the laboratory, and detailed process is:

Get 200 milliliters of rice husks under the state of nature, remove shrivelled kernel and foreign material, rice husk is joined in 200 milliliter 6% the hydrochloric acid soln, boil half an hour on electric furnace under the normal pressure, the acid solution that desalts cleans with ion exchanged water, and finish scavenging solution PH＞5, drains; Rice husk is contained in the furnace pot, place retort furnace, 580 ℃ of following thermostatically heating burnings, promptly got white products in one hour, outward appearance is a pure white, dioxide-containing silica＞95%, except that metal ion and corresponding negatively charged ion, all the other are carbon residue in the impurity, can be by adjusting burning, after-flame carbon residue, thereby the percentage composition of raising silicon-dioxide.

This product is analyzed through the modern analysis center ICP of Nanjing University (emission of ions spectrum), foreign matter content be (unit: ppm):

Iron: 302; Copper: 5.64; Manganese: 48.6;

Plumbous: 5.28.

(extracts GB10517-89: silicon-dioxide＞=90%; Iron＜=1000; Copper＜=30; Manganese＜=50).

Claims (2)

1, a kind of method with producing white carbon black from husk of rice, it is characterized in that: it comprises following step,

A, at first husk is carried out purifying treatment, available air blast process or sieve method are removed foreign material such as shrivelled kernel and earth in the husk;

B, then husk is removed metallic impurity and bio-ligand and handle, in temperature is under the condition of 0 ℃ of-250 ℃ of scope, in encloses container, be that inorganic acid solution more than 1% is handled husk with hydrogen ion concentration, by agitation and hydrionic effect, metallic impurity or bio-ligand are disintegrated down from husk;

C, then water cleaning are taken out husk from acidic solution, with treated water, clean hydrogen ion, metallic impurity and the bio-ligand on husk surface as distilled water, ion exchanged water, high purity water etc., and drain, and be stand-by;

D, postheating burning husk, begin from indirect heating, make the husk moisture evaporation, and reach its point of ignition, utilize the heat energy of husk own, carry out the albefaction burning, make organic substance and charcoal perfect combustion, temperature is controlled at more than 350 ℃, needs in the combustion processes to ventilate, be supplemental oxygen, and discharge products of combustion;

E, at last product is pulverized, the white carbon black form after the burning is the form that silicon-dioxide exists in husk, can require to pulverize according to user's particle diameter get product, then packing.

2, method of producing white carbon black with paddy according to claim 1 is characterized in that: can replace producing white carbon black from husk of rice with straw.