A method for preparing high-purity basic copper carbonate

Abstract

The present invention relates to the technical field of chemical product preparation, and more specifically, to a method for preparing high-purity basic copper carbonate. The key technical solution comprises the following steps: S1, obtaining an ammonium carbonate solution; S2, adding a copper-containing compound to the ammonium carbonate solution, stirring in a water bath, and separating the solid and liquid after the reaction is complete to obtain a copper-based precursor and ammoniacal copper carbonate solution; S3, adding the copper-based precursor to water, heating and decomposing the solution under negative pressure to obtain high-purity basic copper carbonate; S4, heating and decomposing the ammoniacal copper carbonate solution under negative pressure to obtain ordinary basic copper carbonate. The present invention has the advantages of reducing raw material costs and increasing the purity and yield of basic copper carbonate.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical product preparation, and more particularly to a method for preparing high-purity basic copper carbonate. Background Art

[0002] Basic copper carbonate is an important copper salt product. It is used in the inorganic salt industry to prepare various copper compounds, in the organic industry as a catalyst for organic synthesis, and in the copper-tin alloy electroplating industry as a copper additive. It is also used in fireworks manufacturing, pigments, as a smut preventer, in electronic ceramics, and as a dealkalizer for crude oil storage. Furthermore, in the UK and the US, basic copper carbonate is used as a wood preservative, a water algaecide, in containerized seedling cultivation, a crop fungicide, and a feed additive. Basic copper carbonate has a wide range of applications.

[0003] At present, the most commonly used production methods for basic copper carbonate are acid-base neutralization method and ammonia method.

[0004] The acid-base neutralization method uses copper salts and alkali metal carbonates as raw materials, controlling the reaction temperature at 40-70°C and a weakly acidic pH to produce basic copper carbonate. This method is low-cost and simple to operate; however, it produces a large amount of wastewater, and the product contains a large number of difficult-to-remove impurities.

[0005] The ammonia process uses metallic copper and ammonium carbonate as raw materials. Air or oxygen is introduced to oxidize the metallic copper. The pH and reaction temperature are controlled, and excess carbonate and ammonia in the solution are separated through stripping, steam stripping, and vacuum ammonia evaporation to produce basic copper carbonate. This method produces high-quality basic copper carbonate with minimal wastewater, but requires significant equipment investment and raw material costs. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the object of the present invention is to provide a method for preparing high-purity basic copper carbonate, which has the advantages of improving the purity of basic copper carbonate and reducing costs.

[0007] The above technical objectives of the present invention are achieved through the following technical solutions: a method for preparing high-purity basic copper carbonate, comprising the following steps:

[0008] S1, obtaining ammonium carbonate solution;

[0009] S2, adding the copper-containing compound to the ammonium carbonate solution, stirring in a water bath, and separating the solid and liquid after the reaction is complete to obtain a copper-based precursor and ammonia copper carbonate solution;

[0010] S3, adding the copper-based precursor to water, heating and decomposing it under negative pressure to obtain high-purity basic copper carbonate;

[0011] S4, heating and decomposing the copper carbonate ammonia solution under negative pressure to obtain common basic copper carbonate.

[0012] In one embodiment, the concentration of the ammonium carbonate solution is 50-900 g / L.

[0013] In one embodiment, the step S1 further includes adjusting the pH of the ammonium carbonate solution to 8-10.

[0014] In one embodiment, the copper-containing compound includes one or more of copper oxide, copper hydroxide and common basic copper carbonate.

[0015] In one embodiment, the molar ratio of the ammonium carbonate solution to the copper-containing compound is 1.1:1 to 4.5:1.

[0016] In one embodiment, the water bath temperature is 10-70°C.

[0017] In one embodiment, the water bath stirring rate is 100-600 r / min, and the stirring time is 15-300 min.

[0018] In one embodiment, the weight ratio of water to the copper-based precursor is 2:1 to 10:1.

[0019] In one embodiment, the negative pressure of S3 and S4 are both -0.001 to -0.1 MPa.

[0020] The above-mentioned method for preparing high-purity basic copper carbonate has the following beneficial effects:

[0021] First, the high-purity basic copper carbonate prepared by the present invention has a high yield, with a yield of up to 82%;

[0022] Secondly, the present invention adopts the coordination deposition method to significantly reduce the impurities in basic copper carbonate and improve the purity of basic copper carbonate. At the same time, ordinary basic copper carbonate prepared by the present invention can also be added as a raw material of copper-containing compounds to remove impurities and purify basic copper carbonate.

[0023] Third, the present invention uses low-cost copper-containing compounds to replace high-purity basic copper carbonate of metallic copper, thereby reducing raw material costs without increasing capital investment in additional equipment. The operation method is simple and suitable for industrialization. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic flow diagram of the present invention;

[0025] Figure 2 is a SEM image of the copper-based precursor in Example 1;

[0026] Figure 3 is a SEM image of high-purity basic copper carbonate in Example 1;

[0027] Figure 4 This is the XRD comparison diagram of the high-purity basic copper carbonate in Example 1. DETAILED DESCRIPTION

[0028] The present invention is described in further detail below in conjunction with the embodiments. It should be noted that the embodiments described below are intended to facilitate understanding of the present invention and are not intended to limit the present invention in any way. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as those of ordinary skill in the art to which the present invention belongs. In the event of a conflict, the definitions in this specification shall prevail.

[0029] As used herein, the term "prepared from" is synonymous with "comprising." As used herein, the terms "comprising," "including," "having," "containing," or any other variations thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises the listed elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0030] The conjunction "consisting of" excludes any unspecified element, step, or component. If used in a claim, this phrase renders the claim closed, excluding materials other than those described, except for conventional impurities associated therewith. When the phrase "consisting of" appears in a clause of the body of a claim, rather than immediately following the subject matter, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.

[0031] When amount, concentration or other value or parameter is represented with range, preferred range or the range that a series of upper preferred value and lower preferred value limit are expressed, this should be understood as specifically disclosing all ranges formed by any pairing of any range upper limit or preferred value and any range lower limit or preferred value, no matter whether this range is disclosed separately.For example, when disclosing scope "1 to 5", described scope should be interpreted as including scope "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5" etc.When numerical range is described in this article, unless otherwise stated, otherwise this scope is intended to include its end value and all integers and fractions within this range.

[0032] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0033] See Figure 1 A method for preparing high-purity basic copper carbonate comprises the following steps:

[0034] S1, obtaining ammonium carbonate solution;

[0035] In actual operation, ammonium carbonate solution can be prepared by directly dissolving ammonium carbonate solid in water, or by reacting ammonia water, carbon dioxide, ammonium bicarbonate and water to prepare the ammonium carbonate solution.

[0036] S2. Add the copper-containing compound to the ammonium carbonate solution, stir in a water bath, and separate the solid and liquid after the reaction is complete to obtain a copper-based precursor and ammoniacal copper carbonate solution;

[0037] In actual operation, whether the reaction is complete is determined by observing whether blue-purple or dark-purple crystals are completely formed during the reaction.

[0038] S3, adding the copper-based precursor to water, heating and decomposing under negative pressure to obtain high-purity basic copper carbonate;

[0039] In actual operation, the copper-based precursor is mixed with water for slurrying, and then heated under negative pressure to evaporate the ammonia, and then the solid-liquid separation is performed to obtain high-purity basic copper carbonate.

[0040] S4, heating and decomposing the copper carbonate ammonia solution under negative pressure to obtain ordinary basic copper carbonate;

[0041] The copper carbonate ammonia solution is heated under negative pressure to evaporate the ammonia gas, and then the solid-liquid separation is performed to obtain ordinary basic copper carbonate.

[0042] The principle of this invention is that the copper-containing compound used as the raw material contains impurities such as chloride, sulfate, and heavy metal ions such as iron, lead, zinc, and nickel. During the reaction, these impurities dissolve in the copper carbonate ammonia solution and cannot be filtered out. Through a coordinated precipitation method, copper ions react with ammonium carbonate in solution to form a copper-based precursor solid, which can be separated from the impurities. The copper-based precursor is then heated and decomposed in water to produce basic copper carbonate.

[0043] The basic copper carbonate obtained through the above steps has a high yield, up to 82%, and can also improve the purity of the basic copper carbonate. Meanwhile, the obtained ordinary basic copper carbonate can also be added as a raw material for a copper-containing compound to remove impurities and purify the basic copper carbonate. The present invention uses an inexpensive copper-containing compound instead of metallic copper to produce high-purity basic copper carbonate, thereby reducing raw material costs without increasing the capital investment in additional equipment. The operation method is simple and suitable for industrialization.

[0044] Specifically, the concentration of the ammonium carbonate solution is 50 to 900 g / L.

[0045] Specifically, S1 further includes adjusting the pH of the ammonium carbonate solution to 8-10.

[0046] Specifically, the copper-containing compound includes one or more of copper oxide and copper hydroxide.

[0047] Specifically, the molar ratio of the ammonium carbonate solution to the copper-containing compound is 1.1:1 to 4.5:1.

[0048] Specifically, the water bath temperature is 10-70°C.

[0049] Specifically, the stirring rate of the water bath is 100 to 600 r / min, and the stirring time is 15 to 300 min.

[0050] Specifically, the weight ratio of water to the copper-based precursor is 2:1 to 10:1.

[0051] Specifically, the negative pressure of S3 and S4 is -0.001 to -0.1 MPa.

[0052] The following are specific examples:

[0053] Example 1

[0054] A method for preparing high-purity basic copper carbonate comprises the following steps:

[0055] S1. Dissolve 200 g of ammonium carbonate in 400 ml of water to obtain an ammonium carbonate solution;

[0056] S2. Add 150 g of copper hydroxide to the ammonium carbonate solution, stir in a water bath at 50° C. for 120 min, separate the solid and liquid, and obtain a copper-based precursor and ammoniacal copper carbonate solution;

[0057] S3, adding the copper-based precursor to water for slurrying, heating and distilling ammonia under a negative pressure of -0.005 MPa to precipitate a green solid powder, washing and filtering to obtain high-purity basic copper carbonate;

[0058] S4. The copper carbonate ammonia solution is heated under a negative pressure of -0.005 MPa to evaporate ammonia, and a green solid powder is precipitated. After washing and filtering, ordinary basic copper carbonate is obtained.

[0059] like Figure 2 As shown, the copper-based precursor in Example 1 was subjected to scanning electron microscopy (SEM) analysis. Figure 2 The image shown is at 100X, and the copper-based precursor in Example 1 is a square columnar substance.

[0060] like Figure 3-4 As shown, the high-purity basic copper carbonate in Example 1 was subjected to scanning electron microscope (SEM) analysis and XRD analysis. Figure 2 The image shown is 1.00KX, and the high-purity basic copper carbonate is uniform in size, without impurities, and has high purity; Figure 4 The XRD pattern can further confirm that the product is basic copper carbonate.

[0061] Example 2

[0062] S1. Dissolve 100 g of ammonium bicarbonate in 400 ml of water, and add 25% ammonia water to adjust the pH to 9.5 to obtain an ammonium carbonate solution.

[0063] S2. Add 80 g of copper hydroxide to the ammonium carbonate solution, stir in a water bath at 20° C. for 60 min, separate the solid and liquid, and obtain a copper-based precursor and ammonia copper carbonate solution;

[0064] S3, adding the copper-based precursor to water for slurrying, heating and distilling ammonia under a negative pressure of -0.06 MPa to precipitate a green solid powder, washing and filtering to obtain high-purity basic copper carbonate;

[0065] S4. The copper carbonate ammonia solution is heated under a negative pressure of -0.06 MPa to evaporate ammonia, and a green solid powder is precipitated. After washing and filtering, ordinary basic copper carbonate is obtained.

[0066] Example 3

[0067] (1) 300 ml of 25% ammonia water and 100 ml of water were placed in a sealed reaction vessel with stirring, and carbon dioxide was introduced until the pH reached 8.7 to obtain an ammonium carbonate solution;

[0068] (2) adding 50 g of copper oxide to ammonium carbonate solution, stirring in a water bath at 60° C. for 300 min, separating the solid and liquid, and obtaining a copper-based precursor and copper carbonate ammonia solution;

[0069] (3) adding the copper-based precursor to water for slurrying, heating and distilling ammonia under a negative pressure of -0.02 MPa to precipitate a green solid powder, which is then washed and filtered to obtain high-purity basic copper carbonate;

[0070] (4) The copper carbonate ammonia solution is heated under a negative pressure of -0.02 MPa to evaporate ammonia, and a green solid powder is precipitated. After washing and filtering, ordinary basic copper carbonate is obtained.

[0071] The chemical indicators of the high-purity basic copper carbonate prepared in Examples 1-3 of the present invention are shown in the following table:

[0072] Test items (%) Example 1 Example 2 Example 3 Copper (Cu) 56.08 55.91 56.2 Sodium(Na) <0.0010 <0.0010 <0.0010 Iron (Fe) 0.0006 0.0005 0.0006 Lead (Pb) <0.0005 <0.0005 <0.0005 Zinc (Zn) <0.0001 <0.0001 <0.0001 Calcium (Ca) <0.0005 <0.0005 <0.0005 Chromium (Cr) 0.0001 0.0004 0.00003 Cadmium (Cd) <0.00001 <0.00001 <0.00001 Arsenic (As) <0.000002 0.000007 0.000004 Hydrochloric acid insoluble matter 0.007 0.006 0.006 Chloride (as Cl) 0.0067 0.004 0.0081 <![CDATA[Sulfate (calculated as SO4)]]> <0.05 <0.05 <0.05

[0073] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A method for preparing high-purity basic copper carbonate, characterized in that: The following steps are involved: S1, obtaining ammonium carbonate solution; S2. Add the copper-containing compound to the ammonium carbonate solution, stir in a water bath, and separate the solid and liquid after the reaction is complete to obtain a copper-based precursor and ammonia copper carbonate solution, wherein the molar ratio of the ammonium carbonate solution to the copper-containing compound is 1.1:1 to 4.5:1; S3, adding the copper-based precursor to water, heating and decomposing it under negative pressure to obtain high-purity basic copper carbonate; S4, heating and decomposing the copper carbonate ammonia solution under negative pressure to obtain common basic copper carbonate; The negative pressures of S3 and S4 are both -0.001~-0.1MPa.

2. The method for preparing high-purity basic copper carbonate according to claim 1, wherein: The concentration of the ammonium carbonate solution is 50-900 g / L.

3. The method for preparing high-purity basic copper carbonate according to claim 1, wherein: The step S1 further includes adjusting the pH of the ammonium carbonate solution to 8-10.

4. The method for preparing high-purity basic copper carbonate according to claim 1, wherein: The copper-containing compound includes one or more of copper oxide, copper hydroxide and common basic copper carbonate.

5. The method for preparing high-purity basic copper carbonate according to claim 1, wherein: The water bath temperature is 10-70°C.

6. The method for preparing high-purity basic copper carbonate according to claim 1, wherein: The water bath stirring rate is 100-600 r / min, and the stirring time is 15-300 min.

7. The method for preparing high-purity basic copper carbonate according to claim 1, wherein: The weight ratio of water to the copper-based precursor is 2:1 to 10:1.

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