Preparation and application of basic copper carbonate_Industrial additives

Preparation and application background and overview of basic copper carbonate

Basic copper carbonate belongs to the field of fine chemicals and is mainly used in organic catalysts, bactericides, electronic ceramics, crude oil storage dealkalizing agents, etc. Usually exists in the form of green basic copper carbonate and blue basic copper carbonate [2Cu(CO)₃·Cu(OH)₂]. It can be used as a coloring agent for low-temperature color glazes. Nowadays, the chemical raw material copper carbonate is mostly used, which is directly mixed into the low-temperature colored glaze.

Preparation and application of basic copper carbonate

1. A method for preparing high-purity basic copper carbonate, which produces no by-products and waste materials, has high raw material utilization, low cost and no pollution. Including the following steps:

(1) Preparation of ammonia water: Pass liquid ammonia into deionized water and liquid ammonia under a pressure of 0.2MPa to prepare ammonia water with a concentration of 10% to 12%, and store it for later use;

(2) Leaching synthesis reaction: Put strip-shaped electrolytic copper with a purity of ≥99.9% and pyridine tribromide into the copper bath, pump in the ammonia water prepared in step (1) until the electrolytic copper is submerged, and then press carbonic acid The ammonium bicarbonate/ammonia water molar ratio is ≥ 2. Add ammonium bicarbonate into the copper bath and use an air compressor to blow air from the bottom of the copper bath so that the air pressure in the copper bath is 1.01×10⁵~ 10⁶Pa, control the reaction temperature to 60℃~70℃ until the reaction meets the sulfuric acid test;

(3) Filtration: Use a pump to extract 3/4 of the copper ammonium solution in the copper bath in step (2) into the filter for coarse filtration, then introduce it into a precision filter for fine filtration, and finally pump it into the reaction kettle;

(4) Thermal decomposition: Use an air compressor to blow air into the reaction kettle, and heat the reaction kettle to 80-100°C to perform secondary oxidation and gas stripping to remove trace amounts of copper that have not been separated after two filtrations. powder, and at the same time, the copper ammonia compound undergoes a decomposition reaction to generate basic copper carbonate. After detecting the decomposition reaction, when the concentration of copper ions in the mixed liquid containing basic copper carbonate is less than 10g/L, the decomposition reaction ends; and the thermally decomposed The water vapor containing ammonia and carbon dioxide enters the condenser with the air, and the carbonized ammonia water generated during condensation is sent to the concentrated ammonia water preparation tank for later use;

(5) Water removal and rinsing: Pour the mixed liquid containing basic copper carbonate obtained by the thermal decomposition reaction into a centrifuge, first remove the mother liquor, and then wash it with deionized water until the chloride ions in the washing water are removed. End washing when the mass concentration is ≤20ppm, and lift out the basic copper carbonate containing a small amount of water from the centrifuge;

(6) Drying and pulverizing: Send the basic copper carbonate containing a small amount of moisture in step (5) to an oven with a set temperature of 50 to 70°C, dry it until the moisture is ≤ 2%, then pulverize it, and pass it through 100 After sieving, they are crushed and packaged to obtain basic copper carbonate products.

2. A method for producing basic copper carbonate from acidic etching waste liquid. The method for producing basic copper carbonate from acidic etching waste liquid includes the following steps:

The step is to pretreat the etching waste liquid, add sodium peroxide to the acidic etching waste liquid and stir the Cu⁺ dispersed in the solution, and all the Cu⁺ will be converted into Cu²⁺;

Step 2: Add a regulator to the pretreated etching waste liquid, filter it to remove insoluble impurities in the solution, and prepare a solution of divalent copper ions;

Step 3: Add the prepared baking soda solution with a mass ratio of 1:6 and the copper ion solution prepared in step 2 simultaneously into the original solution for reaction.

Step 4: After the reaction is complete, filter to obtain basic copper carbonate tide product, and the basic copper carbonate tide product is dried to obtain basic copper carbonate.

Preparation and application of basic copper carbonate

A method for continuously producing high-purity low-chlorine electroplating grade copper oxide from basic copper carbonate, including the following steps:

(1) Pre-fill water into the preparation container, pass liquid ammonia into the preparation container, so that the ammonia concentration in the preparation container reaches 85~135g/L, then pass in high-purity carbon dioxide to prepare carbonized ammonia water, and start cooling at the same time The water pipe valve is cooled by water, and the obtained carbonized ammonia water is poured into the storage container;

(2) Put the copper material into the copper bath, and inject the carbonized ammonia water obtained in step (1) from the storage container into the copper bath;

(3) Seal the copper pool cover and blow in air to react. The reaction proceeds according to the following reaction formula:

2Cu+2(NH₄)₂CO₃+O₂=2Cu(NH₃)₂CO3 +2H₂O

When it is detected that the concentration of copper ions in the cupro ammonia solution reaches 85~120g/L, stop air blowing, add hydrogen peroxide to the cupro ammonia solution and react fully to produce the cupro ammonia solution;

(4) Pour the cupro ammonia solution obtained in step (3) into the filter and filter, and pour the filtrate into the liquid storage container;

(5) Open the double centrifugal thin film evaporator, introduce steam, and pour the filtrate from the trifluoromethoxypyridine storage container obtained in step (4) into the evaporator. The following ammonia evaporation reaction occurs in the evaporator. :

3Cu(NH₃)₂CO₃ +H₂O=2CuCO₃ Cu(OH)₂+6NH₃↑+ CO₂↑

Discharge the mixed liquid containing basic copper carbonate from the bottom of the evaporator and pour it into the storage container;

(6) Start the centrifuge and put the mixed liquid containing basic copper carbonate obtained in step (5) into the centrifuge, shake off the original liquid and then wash it with deionized water before discharging;

(7) Put the material discharged from the centrifuge in step (6) into the oven, and discharge the material when the water content of the material is ≤2%;

(8) Crush the dried material obtained in step (7), sieve through 100 mesh, analyze, weigh, and package to obtain high-purity basic copper carbonate;

(9) Turn on the inner wall non-scaling rotary electric furnace for continuous preparation of electroplating grade copper oxide, add the high-purity basic copper carbonate obtained in step (8) into the rotary electric furnace and calcine to obtain copper oxide powder, and further cool and sieve to obtain oxidized copper. The finished copper product reacts according to the following reaction formula:

CuCO₃·Cu(OH)₂=2CuO+CO₂↑+H₂O.