Preparation method of high-purity barium carbonate_Industrial additives

Background technology of preparation method of high-purity barium carbonate

High-purity barium carbonate powder is an essential raw material for PTC thermal components, and its quality is directly related to the quality of PTC thermal electronic components. The traditional production methods of barium carbonate include carbonization method, metathesis method and toxinite method. Among them, the barium carbonate produced by the metathesis method has very low sulfur content and high purity, which is suitable for the production of PTC. However, the barium carbonate produced by the metathesis method also has shortcomings such as poor consistency, poor crystal form, and high ignition loss. It cannot meet the requirements of high-performance PTC heat. Processing of sensitive components.

Preparation method of high-purity barium carbonate Summary of the invention

In response to the above situation, the present invention provides a method for preparing high-purity barium carbonate with uniform particle size and good shape. The preparation method is as follows:

(1) Add 50-100 parts by mass of barium hydroxide to 500-1000 parts by mass of double distilled water, stir and dissolve in the reaction kettle at 40-80°C, and prepare a barium hydroxide solution;

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(2) Add 100-200 parts by mass of ammonium bicarbonate to 500-1000 parts by mass of twice-distilled water, stir and dissolve at room temperature in a container, and prepare an ammonium bicarbonate solution;

(3) Add 1-10 parts by mass of ethanol active agent to the barium hydroxide solution prepared in step (I), H. Stir at a constant temperature of 30-80°C for 30–90min;

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(4) Add the ammonium bicarbonate solution prepared in step (2) dropwise into the reaction kettle of step (1) at a certain dropping speed, stir and react with a stirrer at 40-60°C for 1-5 hours ;

(5) Add the reaction material completed in step (4) to a centrifuge for centrifugal separation, and rinse the separated solid with double distilled water;

(6) Add the rinsed solid into a roasting furnace and roast for a certain time to obtain high-purity barium carbonate.

The beneficial effects of the present invention are: using barium hydroxide and ammonium bicarbonate as raw materials, the reaction product is single, and except for barium carbonate, the rest of the products can be collected and discharged in the form of gas. At the same time, adding surfactant before the reaction generates precipitation can solve the problem of agglomeration of precipitation and fully shorten the digestion time of precipitation, realize the transformation of the product from rod-shaped to spherical crystal structure, and improve the uniformity of product particle size. Methoxy group Phenylboric acid. In addition, the roasting furnace adopts temperature gradient online control technology, which effectively reduces the impact of roasting conditions on the characteristics of barium carbonate powder, reduces the chance of aggregation and sintering of barium carbonate powder, and ensures the uniformity of product particle size and structure. stability and product quality, and a good crystal structure was obtained.

Preparation method of high purity barium carbonate Preparation method

Add 50g of barium hydroxide to 50g of 5ethoxycarbonylbenzeneboronic acid in twice-distilled water, stir and dissolve it in the reaction kettle at 60°C, and prepare a barium hydroxide solution; at the same time, add 100g of ammonium bicarbonate to Stir and dissolve 500g of double distilled water in a container at room temperature to prepare an ammonium bicarbonate solution; further add 3g of fatty acid glycerol to the barium hydroxide solution, and stir at a constant temperature of 50°C for 60 minutes; then add the carbonic acid solution The ammonium hydrogen solution was added dropwise to the reaction kettle containing the barium hydroxide solution at a dropping speed of 5g/min, and the reaction was stirred at 50 rpm at 60°C for 3 hours; the completed reaction materials were added to the centrifuge for centrifugation. , and rinse the separated solid with twice distilled water; finally, add the rinsed solid to the roasting furnace and roast it at 250°C for 90 minutes in the first stage, and roast it at 600°C for 60 minutes in the second stage to obtain high-purity barium carbonate. .