Method for continuously and automatically saponifying extraction agent through calcium

Abstract

The invention relates to the technical field of metallurgy and chemical industry, in particular to a continuous automatic calcium saponification extraction agent method which comprises the following steps: placing calcium oxide or calcium hydroxide powder in pure water for constant volume, and carrying out digestion reaction to obtain calcium hydroxide slurry; mixing the calcium hydroxide slurry with an ammonia salt solution, and filtering to obtain an ammonia-calcium composite clear solution; the ammonia-calcium composite clear liquid and the blank organic phase are subjected to a continuous saponification reaction, saponification wastewater is discharged, and the reacted calcium saponification organic phase is subjected to extraction separation; according to the calcium saponification extraction method, the ammonium-containing aqueous solution is used as a raw material, ammonium radicals are recycled, ammonia-nitrogen wastewater is not generated in the saponification and extraction process, the pollution of the ammonia-nitrogen wastewater to the environment can be eliminated, the water circulation rate after wastewater treatment can reach 93.3% or above, and the water circulation rate can reach 93.3% or above. Compared with an original process method, the average generation amount of calcium saponification organic phases is reduced by 64% or above, and a new stage is achieved in the aspect of environmental protection.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgy and chemical industry, and in particular to a method for continuous and automated calcium saponification of an extractant. Background Art

[0002] Liquid-liquid extraction refers to the separation technology using two or more liquid phases that are basically immiscible with each other. It is a process of transferring the required substance from one liquid phase to another. It is particularly suitable for elements with similar chemical properties that are difficult to separate by conventional methods. Extraction separation is an important hydrometallurgical method. During the extraction process, in order to increase and stabilize the ion loading capacity and separation factor of the organic phase of the extractant, most of the organic phase of the extractant needs to be saponified with sodium hydroxide or ammonia water before the extraction reaction, which is called sodium soap or ammonia soap. This type of saponification technology is widely used in my country and is introduced in great detail. For example, Xu Guangxian, chief editor, Rare Earth, Rare Earth Complete Separation Process of Medium Yttrium-Rich Europium Ion Rare Earth Ore; Ammoniated P507 Solvent Extraction Separation Process of Mixed Rare Earths, etc. are all introduced in detail.

[0003] After the saponified organic phase undergoes ion exchange with the element to be extracted, the organic phase is loaded with the element to be extracted, and the organic phase can be recycled after back extraction; the aqueous phase is a sodium or ammonium salt solution, and a large amount of ammonium ions in the wastewater will cause pollution to the environment. Summary of the invention

[0004] The purpose of the present invention is to provide a method for continuous and automated calcium saponification of an extractant, aiming to solve the problem that wastewater pollutes the environment after ion exchange between the existing saponified organic phase and the element to be extracted.

[0005] To achieve the above object, the present invention provides a method for continuous automated calcium saponification of an extractant, comprising the following steps:

[0006] Calcium oxide or calcium hydroxide powder is placed in pure water to make up the volume, and a digestion reaction is performed to obtain calcium hydroxide slurry;

[0007] The calcium hydroxide slurry is mixed with an ammonia salt solution, and filtered to obtain an ammonia-calcium composite clear solution;

[0008] The ammonia-calcium composite clear liquid and the blank organic phase are subjected to continuous saponification reaction, saponification wastewater is discharged, and the calcium saponification organic phase after the reaction is extracted and separated;

[0009] The saponification wastewater is allowed to settle and the floating oil is removed to purify the saponification wastewater.

[0010] The specific method of taking calcium oxide or calcium hydroxide powder and placing it in pure water to make up the volume and performing a digestion reaction to obtain calcium hydroxide slurry is as follows:

[0011] Take 100g of calcium oxide or calcium hydroxide powder and add it to a 2L beaker, and add pure water to make up to 0.8L;

[0012] The beaker was placed in a thermostatic water bath at a constant temperature of 60° C., and an electromagnetic stirrer was started for digestion for 60 minutes to obtain calcium hydroxide slurry.

[0013] The calcium oxide or calcium hydroxide powder has a content of 95.25%, acid insoluble matter ≤ 0.1%, Fe2O3 0.008%, SiO2 0.024%, Al2O3 0.014%, and passes through a 100-mesh sieve.

[0014] Wherein, the ammonia salt solution is an ammonium chloride solution containing 30-31% HCL, and the ammonia salt solution is 6 mol / L.

[0015] The specific method of continuously saponifying the ammonia-calcium composite clear liquid and the blank organic phase, discharging the saponified wastewater, and extracting and separating the calcium saponified organic phase after the reaction is as follows:

[0016] Get P507 extractant and sulfonated kerosene diluent in equal volume ratio and mix them to prepare a blank organic phase;

[0017] Take 500 ml of the blank organic phase and place it in a 1L beaker, and place it in a constant temperature water bath to preheat at 50°C;

[0018] Start the electromagnetic stirrer, then add the ammonia-calcium composite clear solution at a saponification degree of 0.48 to carry out continuous saponification reaction for 30 minutes, then let it stand for 60 minutes and measure the saponification degree;

[0019] Use a separatory funnel to discharge the saponification wastewater and extract and separate the calcium saponification organic phase.

[0020] The continuous saponification reaction requires the addition of an auxiliary extractant, which is calcium chloride, and the calcium chloride content is controlled to be above 2 g / L.

[0021] The specific method of purifying the saponification wastewater by allowing the saponification wastewater to settle and remove the floating oil is as follows:

[0022] The saponified wastewater is collected and allowed to stand, the pH is adjusted using an acidic solution, and then the adjusted wastewater is subjected to a precipitation treatment;

[0023] Add activated carbon to the settled wastewater to adsorb and remove floating oil on the surface and deep layers;

[0024] The wastewater after oil removal is filtered using membrane separation technology, and the pH is adjusted to the discharge standard using alkaline solution.

[0025] The invention discloses a method for preparing a continuous and automated calcium saponification extractant. The method comprises the following steps: taking calcium oxide or calcium hydroxide powder, placing it in pure water to a fixed volume, and performing a digestion reaction to obtain calcium hydroxide slurry; mixing the calcium hydroxide slurry with an ammonia salt solution, and filtering the mixture to obtain an ammonia-calcium composite clear liquid; performing a continuous saponification reaction on the ammonia-calcium composite clear liquid and a blank organic phase, discharging saponified waste water, and extracting and separating the calcium saponified organic phase after the reaction; and statically settling the saponified waste water, removing the floating oil, and purifying the saponified waste water. The calcium saponification extraction method uses an ammonium-containing aqueous solution as a raw material, and ammonium radicals are recycled. No ammonia nitrogen waste water is generated during the saponification and extraction process, and the pollution of the ammonia nitrogen waste water to the environment can be eliminated. The water circulation rate after the waste water is treated can reach more than 93.3%, and the average amount of the calcium saponified organic phase extracted by the original process method is reduced by more than 64%. The method has industrial promotion value, reaches a new level in terms of green environmental protection, and solves the problem that the waste water pollutes the environment after the existing saponified organic phase performs ion exchange with the element to be extracted. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 The present invention provides a flow chart of a method for continuous automated calcium saponification of an extractant.

[0028] Figure 2 The invention is a flow chart of a specific method of taking calcium oxide or calcium hydroxide powder, placing it in pure water to make up the volume, and carrying out a digestion reaction to obtain calcium hydroxide slurry.

[0029] Figure 3 The invention is a flow chart of a specific method of continuously saponifying the ammonia-calcium composite clear liquid and a blank organic phase, discharging saponification waste water, and extracting and separating the calcium saponified organic phase after the reaction.

[0030] Figure 4 The present invention is a flow chart of a specific method for purifying the saponification wastewater by allowing the saponification wastewater to settle and remove the floating oil.

[0031] Figure 5 This is a schematic diagram showing the effect of different digestion water on the amount of foam produced.

[0032] Figure 6 This is a schematic diagram of the effect of different water samples on the production of three-phase substances. DETAILED DESCRIPTION

[0033] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0034] See also Figures 1 to 6 The present invention provides a method for continuous automated calcium saponification of an extractant, comprising the following steps:

[0035] S1: Calcium oxide or calcium hydroxide powder is placed in pure water to make up the volume, and a digestion reaction is performed to obtain calcium hydroxide slurry;

[0036] Specific method:

[0037] S11 Take 100g of calcium oxide or calcium hydroxide powder and add it to a 2L beaker, and add pure water to make up to 0.8L;

[0038] In the embodiment of the present invention, the calcium oxide or calcium hydroxide powder has a content of 95.25%, acid insoluble matter ≤ 0.1%, Fe2O3 0.008%, SiO2 0.024%, Al2O3 0.014%, and passes through a 100-mesh sieve.

[0039] S12: placing the beaker in a constant temperature water bath at 60°C, starting an electromagnetic stirrer for 60 minutes to obtain a calcium hydroxide slurry.

[0040] S2: mixing the calcium hydroxide slurry with an ammonia salt solution and filtering to obtain an ammonia-calcium composite clear solution;

[0041] In the embodiment of the present invention, the ammonia salt solution is an ammonium chloride solution containing 30-31% HCL, and the ammonia salt solution is 6 mol / L.

[0042] S3: continuously saponifying the ammonia-calcium composite clear liquid and the blank organic phase, discharging the saponification wastewater, and extracting and separating the calcium saponified organic phase after the reaction.

[0043] Specific method:

[0044] S31 obtain an equal volume ratio of P507 extractant and sulfonated kerosene diluent, mix them, and prepare a blank organic phase;

[0045] S32 Take 500 ml of the blank organic phase and place it in a 1L beaker, and place it in a constant temperature water bath to preheat at 50°C;

[0046] S33: start the electromagnetic stirrer, add the ammonia-calcium composite clear solution at a saponification degree of 0.48, perform continuous saponification reaction for 30 minutes, let it stand for 60 minutes, and measure the saponification degree;

[0047] In the embodiment of the present invention, the continuous saponification reaction requires the addition of an auxiliary extractant, the auxiliary extractant is calcium chloride, and the calcium chloride content is controlled to be above 2 g / L.

[0048] S34 uses a separatory funnel to discharge saponification wastewater and extract and separate the calcium saponification organic phase.

[0049] S4 is to place the saponification wastewater for settling and remove floating oil to purify the saponification wastewater.

[0050] Specific method:

[0051] S41 collects the saponification wastewater and allows it to stand, uses an acidic solution to adjust the pH, and then performs a precipitation treatment on the adjusted wastewater;

[0052] In the embodiment of the present invention, the acidic solution is sulfuric acid, and the pH of the wastewater is adjusted to acidic so that the heavy metal ions in the wastewater are in a precipitated state to facilitate subsequent treatment. The purpose of precipitation is to precipitate the heavy metals in the wastewater.

[0053] S42 adds activated carbon to the wastewater after sedimentation to adsorb and remove floating oil on the surface and deep layers;

[0054] In the embodiment of the present invention, while adding activated carbon to adsorb and remove the floating oil on the surface and deep layer, the organic matter in the wastewater can also be removed.

[0055] S43 uses membrane separation technology to filter the wastewater after oil removal and uses alkaline solution to adjust the pH to the discharge standard.

[0056] In an embodiment of the present invention, membrane separation technology such as reverse osmosis membrane or ultrafiltration membrane is used to filter the wastewater to remove some soluble substances and particles, and an alkaline solution is used for neutralization and adjustment to adjust the pH value of the wastewater to an appropriate range so that the water quality meets the discharge standard.

[0057] The invention discloses a method for preparing a continuous and automated calcium saponification extractant. The method comprises the following steps: taking calcium oxide or calcium hydroxide powder, placing it in pure water to a fixed volume, and performing a digestion reaction to obtain calcium hydroxide slurry; mixing the calcium hydroxide slurry with an ammonia salt solution, and filtering the mixture to obtain an ammonia-calcium composite clear liquid; performing a continuous saponification reaction on the ammonia-calcium composite clear liquid and a blank organic phase, discharging saponified waste water, and extracting and separating the calcium saponified organic phase after the reaction; and statically settling the saponified waste water, removing the floating oil, and purifying the saponified waste water. The calcium saponification extraction method uses an ammonium-containing aqueous solution as a raw material, and ammonium radicals are recycled. No ammonia nitrogen waste water is generated during the saponification and extraction process, and the pollution of the ammonia nitrogen waste water to the environment can be eliminated. The water circulation rate after the waste water is treated can reach more than 93.3%, and the average amount of the calcium saponified organic phase extracted by the original process method is reduced by more than 64%. The method has industrial promotion value, reaches a new level in terms of green environmental protection, and solves the problem that the waste water pollutes the environment after the existing saponified organic phase performs ion exchange with the element to be extracted.

[0058] In order to better understand the present technical solution, the following embodiments are provided for further explanation:

[0059] Example 1

[0060] Analysis of components of saponification wastewater

[0061] The water phase of the saponification wastewater outlet was tested, and the test results are shown in the following table:

[0062]

[0063] The test results show that the saponification wastewater contains a small amount of extractant that causes a high COD, but no heavy metals or rare earth elements exceed the standard. It also contains a small amount of calcium chloride that can be used as an auxiliary extractant. It is preliminarily judged that the wastewater can be reused for calcium oxide digestion and slurry preparation to produce calcium hydroxide slurry, and then the slurry is used in the calcium saponification process without introducing impurities that affect production.

[0064] Example 2

[0065] Experiment on digestion and slurry preparation of calcium saponification wastewater

[0066] Three water samples were taken respectively: pure water was recorded as ①, the water sample of the calcium saponification wastewater from the calcium saponification production line after the floating oil was removed by standing was recorded as ②, and the water sample of the calcium saponification wastewater from the calcium saponification production line after the floating oil was removed by standing and then deep oil removal by activated carbon adsorption was recorded as ③.

[0067] Take 100g of calcium oxide and add it to a 2L beaker, add the test water sample to make up to 0.8L, place it in a constant temperature water bath at 60℃, start the electromagnetic stirrer to digest for 60 minutes to obtain calcium hydroxide slurry, and finally add the same water sample to make up to 1L to titrate the alkalinity for use.

[0068] After the reaction is completed, the slurry is Figure 2As shown, a large amount of foam is generated during the slurry mixing of water sample No. ②, which seriously interferes with the slurry mixing work; a small amount of foam is generated during the slurry mixing of water sample No. ③, which does not affect the slurry mixing work; and only a few bubbles are generated in the reference water sample No. ①.

[0069] Example 3

[0070] Calcium saponification experiment of slurry prepared with different water samples

[0071] The effects of different water samples on the production of three-phase substances (calcium saponified organic phase) were investigated separately. Figure 3 As shown. The slurry prepared by water sample No. ② has more three-phase products formed by calcium saponification than the slurry prepared by reference water sample No. ①, and the saponification degree is slightly lower. It is speculated that the oil removal of water sample No. ② is not thorough, and the residual extractant in the digestion process is over-saponified to form a stubborn oil film that interferes with the slurry's participation in the reaction; the slurry prepared by water sample No. ③ has less three-phase products formed by calcium saponification than the slurry prepared by reference water sample No. ①, and the saponification degree is slightly higher. It is speculated that after the interference of oil is eliminated in water sample No. ③, a small amount of calcium chloride assists in extraction and improves the saponification efficiency. Therefore, water sample No. ③ (the water sample after calcium saponification wastewater of the calcium saponification production line is left to stand to remove the floating oil and then deeply deoiled by activated carbon adsorption) can replace pure water as water for lime digestion and slurry preparation, realizing the recycling of calcium saponification wastewater.

[0072] The above disclosure is only a preferred embodiment of a method for continuous automated calcium saponification extraction of the present invention. Of course, it cannot be used to limit the scope of the present invention. A person skilled in the art can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A method for continuous automated calcium saponification of an extractant, characterized in that: The following steps are involved: Calcium oxide or calcium hydroxide powder is placed in pure water to make up the volume, and a digestion reaction is performed to obtain calcium hydroxide slurry; The calcium hydroxide slurry is mixed with an ammonia salt solution, and filtered to obtain an ammonia-calcium composite clear solution; The ammonia-calcium composite clear liquid and the blank organic phase are subjected to continuous saponification reaction, saponification wastewater is discharged, and the calcium saponification organic phase after the reaction is extracted and separated; The saponification wastewater is allowed to settle and the floating oil is removed to purify the saponification wastewater.

2. The method for continuous automated calcium saponification of an extractant as claimed in claim 1, characterized in that: The specific method of taking calcium oxide or calcium hydroxide powder and placing it in pure water to make up the volume, and performing a digestion reaction to obtain calcium hydroxide slurry is: Take 100g of calcium oxide or calcium hydroxide powder and add it to a 2L beaker, and add pure water to make up to 0.8L; The beaker was placed in a thermostatic water bath at a constant temperature of 60° C., and an electromagnetic stirrer was started for digestion for 60 minutes to obtain calcium hydroxide slurry.

3. The method for continuous automated calcium saponification of an extractant as claimed in claim 1, characterized in that: The calcium oxide or calcium hydroxide powder has a content of 95.25%, acid insoluble matter ≤0.1%, Fe2O3 0.008%, SiO2 0.024%, Al2O3 0.014%, and passes through a 100-mesh sieve.

4. The method for continuous automated calcium saponification of an extractant as claimed in claim 1, characterized in that: The ammonia salt solution is an ammonium chloride solution containing 30-31% HCL, and the ammonia salt solution is 6 mol / L.

5. The method for continuous automated calcium saponification of an extractant as claimed in claim 1, characterized in that: The specific method of continuously saponifying the ammonia-calcium composite clear liquid and the blank organic phase, discharging the saponification wastewater, and extracting and separating the calcium saponified organic phase after the reaction is as follows: Get P507 extractant and sulfonated kerosene diluent in equal volume ratio and mix them to prepare a blank organic phase; Take 500 ml of the blank organic phase and place it in a 1L beaker, and place it in a constant temperature water bath to preheat at 50°C; Start the electromagnetic stirrer, then add the ammonia-calcium composite clear solution at a saponification degree of 0.48 to carry out continuous saponification reaction for 30 minutes, then let it stand for 60 minutes and measure the saponification degree; Use a separatory funnel to discharge the saponification wastewater and extract and separate the calcium saponification organic phase.

6. The method for continuous automated calcium saponification of an extractant according to claim 1, characterized in that: The continuous saponification reaction requires the addition of an auxiliary extractant, which is calcium chloride, and the calcium chloride content is controlled to be above 2 g / L.

7. The method for continuous automated calcium saponification of an extractant according to claim 1, characterized in that: The specific method of purifying the saponification wastewater by allowing the saponification wastewater to settle and remove the floating oil is as follows: The saponified wastewater is collected and allowed to stand, the pH is adjusted using an acidic solution, and then the adjusted wastewater is subjected to a precipitation treatment; Add activated carbon to the settled wastewater to adsorb and remove floating oil on the surface and deep layers; The wastewater after oil removal is filtered using membrane separation technology, and the pH is adjusted to the discharge standard using alkaline solution.

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