CN1163231A

CN1163231A - Commercial production technology for hydrated sodium-potassium antimonate method

Info

Publication number: CN1163231A
Application number: CN 96118121
Authority: CN
Inventors: 尹作栋; 肖祥湘; 陈效兰; 邱景生
Original assignee: CHEMICAL INDUSTRY INST ZHUZHOU CITY
Current assignee: CHEMICAL INDUSTRY INST ZHUZHOU CITY
Priority date: 1996-04-23
Filing date: 1996-04-23
Publication date: 1997-10-29

Abstract

The production process includes the following steps: preparing basic solution, oxidation of diantimony trioxide powder in water solution of potassium hhdroxide adding hydrogen peroxide solution into potassium antimonate at the conditions of normal pressure and 60-105 deg.C, metathesis between clarified potassium antimonate solution and sodium hydroxide solution to produce hydrate sodium antimonate, filtering to obtain hydrated sodium antimonate, and the reuse of mother liquor by adding proper amount of diantimony trioxide, hydrogen peroxide solution or sodium hydroxide, potassium hhdroxide before returning to oxidation step.

Description

Industrial production process of hydrated sodium-potassium antimonate

The invention relates to a hydrated sodium-potassium antimonate industrial production process, belonging to the class of metal preparation compounds.

Sodium antimonate hydrate, also known as sodium pyroantimonate, is mainly used as a flame retardant, a clarifier for high-grade glass and a milk-white agent for enamel. The common production method of the sodium antimonate hydrate comprises an alkali oxidation method, the requirement on raw materials is strict, a chlorine (salt) oxidation method is easy to cause environmental pollution, the production cost is higher, and the equipment is complex when the sodium antimonate hydrate is produced by a pressurization method.

The invention aims to provide an industrial production process of hydrated sodium antimonate, which can reduce the cost and reduce the production cost.

The main technological process includes adding hydrogen peroxide into potassium hydroxide solution at normal temperature or below 100 deg.c to oxidize antimony trioxide into potassium antimonate, adding sodium sulfide to eliminate heavy metal and clarify to eliminate impurity, adding sodium hydroxide solution to perform double decomposition reaction to obtain hydrated sodium antimonate insoluble in water, filtering and drying.

The invention has the advantages of wide raw material taking range and good product quality: the whiteness is more than or equal to 70, the fluidity is good, the reaction process does not need heating, the energy is saved, the environment is not polluted by waste gas, and the whole reaction process is mild; the potassium hydroxide solution is recycled, and the production cost is reduced.

The process flow of the invention is shown in the attached drawings, and the specific process of the process is described by combining the attached drawings:

raw material preparation

Antimony oxide powder or antimony ore powder, the content of antimony trioxide is not less than 50%

Hydrogen peroxide: industrial grade

Potassium hydroxide:industrial grade

Sodium hydroxide: industrial grade

Sodium sulfide or ammonium sulfide: industrial grade

1. Preparing aqueous solution of potassium hydroxide and sodium hydroxide with certain concentration

A: taking a certain amount of potassium hydroxide to prepare an aqueous solution with the concentration of 14-20 Baume.

B: taking a certain amount of sodium hydroxide to prepare an aqueous solution with the concentration of 10-40 Baume.

The concentration is measured by a specific gravity meter at a temperature of 60 ℃, and the same is true throughout the text.

2. Oxidation reaction

Adding a certain amount of potassium hydroxide solution such as 1000L and 250Kg of antimony oxide powder into an oxidation reaction kettle, adding hydrogen peroxide for oxidation at normal temperature or below 100 ℃, stirring until antimony trioxide is completely converted into potassium antimonate, and carrying out the reaction at normal pressure, wherein the reaction temperature is controlled at 60-1Between 05 ℃. The reaction equation is as follows:

3. removing impurities

After the oxidation reaction is completed, when the impurities of lead and the like need to be removed, a proper amount of sodium sulfide (or ammonium sulfide or potassium sulfide, hydrogen sulfide) solution which is prepared in advance is added, and the concentration and the amount of the sodium sulfide (or ammonium sulfide or potassium sulfide, hydrogen sulfide) solution are specifically determined according to the condition of raw materials. And after five minutes, putting the reaction liquid into a clarifying tank for clarifying and removing impurities,wherein the clarifying time is not less than half an hour.

4. Metathesis reactions

Firstly, adding a water solution with the concentration of 10-40 Baume and containing 62kg of sodium hydroxide into a double decomposition reaction kettle, then pumping a clear potassium antimonate solution, carrying out double decomposition reaction, carrying out the reaction at the normal pressure and the temperature of 50-100 ℃, and properly stirring to convert potassium antimonate into sodium antimonate hydrate which is difficult to dissolve in water, wherein the reaction equation is as follows:

5. separating, and collecting the product from the reaction mixture

And cooling the suspension obtained by the double decomposition reaction to below 50 ℃, filtering, centrifugally drying, drying at the temperature lower than 120 ℃, and packaging to obtain a finished product.

6. Mother liquor treatment

Filtering the mother liquor after the sodium antimonate hydrate, and after qualitative detection, adding a proper amount of antimony trioxide and hydrogen peroxide to carry out oxidation treatment on redundant sodium; or adding a proper amount of sodium hydroxide to treat redundant potassium antimonate. And controlling the reaction temperature at 50-85 ℃ and normal pressure, filtering, detecting by a hydrometer, adding a proper amount of potassium hydroxide, recovering the concentration of the filtrate to 14-20 Baume, and returning to the oxidation process for recycling.

Examples of the present invention are as follows;

example 1

1100L of potassium hydroxide aqueous solution with the concentration of 18 Baume is prepared, 62Kg of sodium hydroxide is prepared into aqueous solution with the concentration of 40 Baume, the potassium hydroxide aqueous solution and 250Kg of antimony oxide powder containing 92.6 percent of antimony trioxide are added into an oxidation reaction kettle, the room temperature is 36 ℃, 220L of 27 percent hydrogen peroxide is added for oxidation under normal pressure, stirring is carried out, the reaction is carried out for releasing heat and heating, the temperature is raised to 90 ℃, after the antimony trioxide is completely converted into potassium antimonate, the hydrogen peroxide is completely decomposed, and the reaction is ended without bubbling. Putting the reaction liquid into a clarifying tank for clarification for half an hour; in the double decomposition reaction kettle, firstly adding the prepared sodium hydroxide aqueous solution, then pumping the potassium antimonate clear solution, carrying out the reaction under normal pressure, controlling the temperature between 50 and 105 ℃ until the potassium antimonate is completely converted into the sodium antimonate hydrate which is insoluble in water, collecting the product from the reaction mixture, namely about 375Kg of the sodium antimonate hydrate with the whiteness of more than or equal to 70, treating the mother liquor, detecting and adding 10Kg of antimony trioxide and 22L of 27 percent hydrogen peroxide to treat the redundant sodium, properly stirring, carrying out the reaction under normal pressure, measuring the temperature of the mother liquor at 55 ℃, adding 25Kg of potassium hydroxide after measuring by a gravimeter, keeping the concentration of the filtrate at 18 baume, and returning to the oxidation process.

Example 2:

preparing 1000L of potassium hydroxide aqueous solution with the concentration of 20 Baume, preparing 60kg of sodium hydroxide into aqueous solution with the concentration of 10 Baume, adding the potassium hydroxide solution and 250kg of antimony ore powder containing 90 percent of antimony trioxide into an oxidation reaction kettle, adding hydrogen peroxide at the room temperature of 20 ℃, stirring, oxidizing under normal pressure, raising the temperature to 80 ℃ due to the reaction heat release, continuously reacting until the antimony trioxide is completely converted into potassium antimonate, and adding 100g of sodium sulfide solution to remove lead impurities when lead removal is needed, wherein the reaction equation is that Clarifying the reaction liquid in clarifying tank for 40 min, adding sodium hydroxide solution and potassium antimonate clarifying liquid in decomposing reactor, reaction at normal pressure and 50-100 deg.c until the potassium antimonate is converted into water insoluble sodium antimonate hydrate, collecting the resultant, i.e. 370Kg sodium antimonate hydrate with whiteness not lower than 70, treating the filtered mother liquid, adding 6Kg sodium hydroxide to treat excessive potassium antimonate, reaction at normal pressure and 50-70 deg.c, stirring and filtering, measuring specific weight, adding 20Kg sodium antimonatePotassium hydroxide, returning to the oxidation process after the concentration is restored to 20 Baume.

Claims

An industrial production process of hydrated sodium and potassium antimonate by a method sequentially comprises the following steps.

1. Preparing potassium hydroxide and sodium hydroxide aqueous solution with certain concentration;
2. and (3) oxidation reaction: adding a certain amount of potassium hydroxide aqueous solution with the concentration of 14-20 Baume and a corresponding amount of antimony oxide powder containing more than 50% of antimony trioxide into an oxidation reaction kettle, adding hydrogen peroxide at normal temperature or below 100 ℃, oxidizing and stirring, and reacting at normal pressure and the temperature of 60-105 ℃ until the antimony trioxide is completely converted into potassium antimonate;
3. after the oxidation reaction is finished, putting the reaction liquid into a clarifying tank for clarification for not less than half an hour;
4. double decomposition reaction, adding 10-40 Baume sodium hydroxide water solution with the same content as antimony trioxide (or potassium antimonate) into a double decomposition reaction kettle, pumping the clarified potassium antimonate solution for double decomposition reaction, and converting the potassium antimonate into water-insoluble hydrated sodium antimonate at normal pressure and 50-100 ℃;
5. collecting the product from the reaction mixture;
6. mother liquor treatment, namely after the mother liquor obtained after filtering the hydrated sodium antimonate is qualitatively detected, adding a proper amount of antimony trioxide and hydrogen peroxide to treat redundant sodium; or adding a proper amount of sodium hydroxide to treat redundant potassium antimonate; the reaction is carried out at 50-85 ℃ and normal pressure, proper potassium hydroxide is added after filtration and detection, the concentration of the filtrate is recovered to 14-20 Baume, and then the oxidation process is returned.