CN1276343A

CN1276343A - Process for preparing activated zinc oxide

Info

Publication number: CN1276343A
Application number: CN99107856A
Authority: CN
Inventors: 王金刚
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-06-03
Filing date: 1999-06-03
Publication date: 2000-12-13
Anticipated expiration: 2019-06-03
Also published as: CN1111510C

Abstract

A process for preparing high-purity active zinc oxide from zinc ash, zinc slag, or zinc ore as raw material includes leaching with ammonia water or ammonium hydrogen carbonate, removing impurities, bleaching-refining with potassium permanganate and H2O2, deamination, drying, deawatering and calcining. The zinc powder is used as reducer. The activated carbon is used as absorbent. The deionized hot water is used for deamination to obtain Zn(OH)2 as intermediate product. Its advantages are no CO2 pollution in calcining, high purity and activity, low cost and saving energy.

Description

Process for preparing activated zinc oxide

The invention belongs to improvement, particularly produce the improvement of high-purity active zinc oxide technology the zinc oxide production technique.

Zinc oxide is a kind of important industrial raw material, and it is widely used in industries such as rubber, oil, coating, pigment, medicine, plays a part very important to the related products quality.High-purity active zinc oxide requires that its impure amount is few, whiteness is high, granularity is little, is the product of being badly in need of in the market.The traditional technology of producing at present highly pure active zinc oxide is divided into two kinds of dry combustion method and wet methods, it is raw material that dry combustion method is chosen zinc ingot metal, utilize the dry combustion method direct oxidation that metallic zinc is converted into zinc oxide, it is regardless of quality, because of the big market that made of the repeatability and the investment of its work is difficult to accept.The more employing yellow soda ash of the wet production active zinc flower precipitator method, its long flow path, the cost height, final quality is also wayward.Now existing people agricultural ammoniacal liquor on probation and bicarbonate of ammonia are made oxygenant, utilize secondary oxidative zinc to do trial for raw material, but still there are problems such as energy consumption height, environmental pollution be serious, cost is also still higher, how high-purity active zinc oxide technology is further improved, become the task of top priority for market provides high-quality, cheap product.

The objective of the invention is to produce with zinc ammonia coordination ion method the improvement of high-purity active zinc oxide technology, making it can be that base-material is produced high-quality active zinc flower with zinc gray, industrial cadmia or zinc ore, and cuts down the consumption of energy and reduce pollution, and cost is declined to a great extent.

The present invention adopt the character of new processing method change intermediates, thereby the energy consumption of greatly reducing has been eliminated carbon dioxide pollution, and cost is declined to a great extent according to material characteristic, and concrete technical process is as follows:

1. effective ingredient leaches:

In this procedure,, before feeding intake, should calculate the wherein content of effective ingredient according to the raw material analysis report because to choose industrial waste zinc gray, cadmia or zinc ore be base-material at every turn.Be standard value according to effective content then, by 1: 4: 0.1-0.3 (mol ratio) added ammoniacal liquor and bicarbonate of ammonia.Wherein to be as the criterion by effective mol ratio weight conversion calculations with existing agricultural ammoniacal liquor be the actual weight of agricultural ammoniacal liquor to ammoniacal liquor.It is mixed adding reactor internal heating to 30-38 ℃, and after question response finished, normal pressure filtered down and obtains filtrate.

2. remove beavy metal impurity:

Contained heavy metal atom is participated in reaction in the raw material, is mixed among the intermediates with similar resultant, can produce harm greatly to quality product, must be separated.3-5% by filtrate weight adds zinc powder, reacts 20-30 minute down at 30-38 ℃, produces replacement(metathesis)reaction, generates heavy metal simple substance, and normal pressure filters and obtains to replace filtrate then.

3. bleach refining:

Acquired displacement filtrate is added the potassium permanganate of 1-3% and the hydrogen peroxide of 4-7% by weight, make the filtrate decolouring bleach, and further residual valence heavy metal ions is oxidized at a low price, add the 1-2% gac more by volume and further absorb residual impurity in the filtrate, keep 10 minutes after-filtration to obtain smart filtrate.

4. deamination drying:

Be as the criterion by volume 1 with the smart filtrate of gained: 10-12 adds deionized water, heat 50-60 ℃, and hydrolysis kept 40-50 minute, obtains Zn (OH) 2 precipitations, and drying dehydration obtains intermediates Zn (OH) 2 dried filter cakes after the filtration.

5. roast dehydration:

Intermediates Zn (OH) 2 dried filter cakes are put into 300-400 ℃ of roasting furnace heating, kept the high-purity active zinc oxide powder after obtaining dewatering 3-4 hour.

This technology also can adopt secondary oxidative zinc as raw material, and it is better then to generate quality product, and this technology is the loss of ammonia of having done minimizing that leaching and removal of impurities handle at normal temperatures, has increased the rate that recycles of ammonia, also filtrate directly can be done the chemical fertilizer application.Saved a large amount of ionized waters owing to having removed spent acid wash water operation from, do not had CO2 to produce in the roast, temperature is low during roast, the time short, greatly reduces energy consumption, has reduced cost.Particularly few by the product granularity behind the multiple-stage treatment, whiteness is high, activity is strong, the consumption through the comparable similar product reduction 30-50% at the same level of the product of trying out this technology of application in rubber industry has the value of applying.

Claims

1, high-purity active zinc oxide new process of production includes effective constituent and leaches, removes beavy metal impurity, dehydration and calcining process in this technology, it is characterized in that concrete technical process is as follows:

1. effective ingredient leaches: adopting zinc gray, cadmia or zinc ore in this operation is base-material, the effective component content of measuring by the chemical examination that feeds intake is a standard, by 1: 4: 0.1-0.3 (mol ratio) adding ammoniacal liquor and bicarbonate of ammonia were after the reactor internal heating extremely reacts end to 30-38 °, normal pressure filters out filtrate

2. remove beavy metal impurity: add zinc powder by filtrate 3-5% (weight ratio),, obtain displacement filtrate 30-38 ℃ of reaction filtration once more in 20-30 minute down,

3. bleach refining: the hydrogen peroxide (above is weight ratio) by displacement filtrate 1-3% adding potassium permanganate and 4-7%, react adding 1-2% gac (volume ratio) after 20-30 minute, keep 10 minutes after-filtration to obtain smart filtrate,

4. deamination drying: with the smart filtrate of gained by 1: 10-12 (volume ratio) adds the deionized water hydrolysis, be heated to 50-60 ℃ and kept 40-50 minute, obtain Zn (OH) 2 precipitations, obtain moisture Zn (OH) 2 filter cakes after the filtration, obtain intermediates Zn (OH) 2 dried filter cakes behind the drying dehydration

5. roast dehydration: intermediates are inserted 300-400 ℃ of roasting furnace internal heating, kept 3-4 hour, the high-purity active zinc oxide powder after obtaining dewatering.