Method for recovering rhenium from alkaline rhenium-containing solution

Abstract

The invention discloses a method for recovering rhenium from an alkaline rhenium-containing solution, and solves the problem of rhenium element loss caused by high impurity content, difficult recycling and the like of the alkaline rhenium-containing solution in the process of producing an ammonium rhenate product by a conventional hydrometallurgy process. A certain amount of sulfuric acid or a sulfuric acid-containing solution is added into the alkaline rhenium-containing solution, and the reaction acidity and the reaction time are controlled, so that the alkaline rhenium-containing solution is acidified and transformed to obtain the acidic rhenium-containing solution. After the acid rhenium-containing solution is purified and filtered, enrichment and recovery of rhenium elements and effective removal and separation of impurity elements can be achieved by adopting extraction agent extraction and ammonia water reverse extraction, the rhenium recovery rate of the system is increased, and efficient utilization of rhenium resources is facilitated. The method is easy to operate, low in cost and easy to master, and the effect of improving the rhenium recovery rate in the ammonium rhenate production process through a conventional hydrometallurgy technology is remarkable.

Description

Technical Field

[0001] The invention relates to the technical field of nonferrous metal metallurgy, in particular to a method for recovering rhenium from an alkaline rhenium-containing solution. Background Art

[0002] Rhenium is a rare metal with a content of 10 -7 %. Rhenium is mostly associated with minerals such as molybdenum, copper, lead, zinc, platinum, tantalum, niobium, and rare earths, and it is difficult to recycle it alone. The global production of rhenium mainly depends on the enrichment and recovery of porphyry copper mines during the recovery of copper and molybdenum. At present, the commonly used rhenium recovery methods in industry are mainly chemical precipitation, ion exchange, and extraction-crystallization.

[0003] The above-mentioned ammonium rhenate purification and preparation processes produce an alkaline rhenium-containing solution in the production process, which contains 2-30g / l of rhenium and has a high recycling value. However, since the solution contains impurity elements such as copper, arsenic, lead, antimony, bismuth, and other solid particulate impurities that are difficult to settle, as well as some residual organic matter, the conventional recycling method of returning the mother liquor to the main process not only fails to effectively remove impurities, but also leads to impurity enrichment, affecting product quality. Therefore, for many years, various manufacturers can only treat this alkaline rhenium-containing solution as waste liquid, resulting in rhenium element loss and low system recovery rate.

[0004] How to solve the impurity problem of alkaline rhenium solution and recover the rhenium element in it economically and reasonably is a topic that all manufacturers have been studying. This process is simple to operate, low in cost, has obvious impurity removal effect, and high rhenium recovery rate, which effectively solves the problem of recycling alkaline rhenium solution. Summary of the invention

[0005] The object of the present invention is to provide a method for recovering rhenium from an alkaline rhenium-containing solution. The specific steps of the method for recovering rhenium from an alkaline rhenium-containing solution are as follows:

[0006] Step 1, acidification transformation process, adding acid solution to the alkaline rhenium-containing solution, stirring, controlling the temperature to (10-50)°C, the stirring time to >0.5h, and the acidity of the transformed liquid to (50-250)g / L, to obtain the transformed liquid;

[0007] Step 2, purification and filtration process, filtering the transformed liquid obtained in step 1 through a filter to remove fine solid impurities and organic matter to obtain a pure acidic rhenium-containing solution;

[0008] Step 3, extraction process, adding the pure acidic rhenium-containing solution obtained in step 2 to an extractant for extraction, controlling the ratio of the pure acidic rhenium-containing solution to the extractant to be (10-80):1, to obtain a rhenium-containing loaded organic phase;

[0009] Step 4, washing process, washing the loaded organic phase obtained in step 3 with pure water, controlling the ratio of pure water to the rhenium-containing loaded organic phase to be (2-10):1, to obtain a pure loaded organic phase;

[0010] Step 5, a stripping process, stripping the pure loaded organic phase obtained in step 4 with aqueous ammonia, controlling the ratio of aqueous ammonia to the pure loaded organic phase to be (0.5-5):1, obtaining a rhenium-containing stripping solution, thereby achieving the purpose of removing impurities and enriching and recovering rhenium.

[0011] Preferably, the acid solution added in step 1 is sulfuric acid or a solution containing sulfuric acid.

[0012] Preferably, the concentration of the aqueous ammonia used in step 5 is (5-20)%.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: the method converts an alkaline rhenium-containing solution with a high impurity content and difficult to recycle into an acidic rhenium-containing solution that can be extracted through sulfuric acid acidification transformation and purification filtration, and achieves the purpose of separating rhenium from impurity elements and enriching and recovering the rhenium element through selective extraction with an extractant and back extraction with ammonia water. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0016] Embodiment 1:

[0017] When ammonium rhenate products are produced by conventional hydrometallurgical processes, an alkaline rhenium-containing solution is produced during the precipitation and crystallization of ammonium rhenate. The rhenium content is 6.75 g / l, and the solution contains 0.088 g / l of arsenic, 0.13 g / l of copper, 0.076 g / l of lead, and other difficult-to-sediment solid particulate impurities and some residual extractants. In this scheme, the alkaline rhenium-containing solution is introduced into a certain proportion of rhenium-containing sulfuric acid solution, stirred, the reaction temperature is controlled to be room temperature, the stirring time is 1.5 hours, the acidity of the liquid after transformation is 160g / l, and the residual extractant and other solid particle impurities are removed by filtering with a security filter to obtain a pure acidic rhenium-containing solution; during the extraction and stripping process of the pure acidic rhenium-containing solution, the extraction temperature is controlled to be room temperature, the extraction phase ratio is 55:1, the washing phase ratio is 3.5:1, and the stripping phase ratio is 1.2:1. The rhenium recovery rate in the extraction and stripping process is 98.75%, and the arsenic, copper, and lead removal rates are 99.87%, 99.71%, and 99.80%, respectively.

[0018] Embodiment 2:

[0019] When ammonium rhenate products are produced by conventional hydrometallurgical processes, an alkaline rhenium-containing solution is produced during the crystallization of ammonium rhenate. The rhenium content is 2.64 g / l, and the solution contains 0.072 g / l of arsenic, 0.084 g / l of copper, 0.066 g / l of lead, and other difficult-to-sediment solid particulate impurities and some residual extractants. In this scheme, a certain proportion of sulfuric acid is added to the alkaline rhenium-containing solution, and the mixture is stirred. The reaction temperature is controlled at 40°C, the stirring time is 1h, and the acidity of the liquid after transformation is 120g / l. The residual extractant and other solid particle impurities are removed by vacuum filtration to obtain a pure acidic rhenium-containing solution. During the extraction and stripping process of the pure acidic rhenium-containing solution, the extraction temperature is controlled at room temperature, the extraction phase ratio is 75:1, the washing phase ratio is 3.5:1, and the stripping phase ratio is 0.95:1. The rhenium recovery rate in the extraction and stripping process is 99.14%, and the removal rates of arsenic, copper, and lead are 99.92%, 99.80%, and 99.71%, respectively.

[0020] Embodiment 3:

[0021] When ammonium rhenate products are produced by conventional hydrometallurgical processes, an alkaline rhenium-containing solution is produced during the recovery of the waste organic phase, with a rhenium content of 15.65 g / l, 0.076 g / l antimony, 0.095 g / l bismuth, and other difficult-to-sediment solid particulate impurities and some residual extractants. In this scheme, the alkaline rhenium-containing solution is introduced into a certain proportion of rhenium-containing sulfuric acid solution, stirred, and the reaction temperature is controlled at 30°C, the stirring time is 2 hours, and the acidity of the liquid after transformation is 180 g / l. The residual extractant and other solid particulate impurities are removed by filtering with a security filter to obtain a pure acidic rhenium-containing solution; during the extraction and stripping of the pure acidic rhenium-containing solution, the extraction temperature is controlled to be room temperature, the extraction phase ratio is 40:1, the washing phase ratio is 4:1, and the stripping phase ratio is 1.5:1. The rhenium recovery rate in the extraction and stripping process is 98.56%, and the antimony and bismuth removal rates are 98.32% and 98.68%, respectively.

[0022] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for recovering rhenium from an alkaline rhenium-containing solution, characterized in that: The method for recovering rhenium from an alkaline rhenium-containing solution comprises the following specific steps: Step 1, acidification transformation process, adding acid solution to the alkaline rhenium-containing solution, stirring, controlling the temperature to (10-50)°C, the stirring time to >0.5h, and the acidity of the transformed liquid to (50-250)g / L, to obtain the transformed liquid; Step 2, purification and filtration process, filtering the transformed liquid obtained in step 1 through a filter to remove fine solid impurities and organic matter to obtain a pure acidic rhenium-containing solution; Step 3, extraction process, adding the pure acidic rhenium-containing solution obtained in step 2 to an extractant for extraction, controlling the ratio of the pure acidic rhenium-containing solution to the extractant to be (10-80):1, to obtain a rhenium-containing loaded organic phase; Step 4, washing process, washing the loaded organic phase obtained in step 3 with pure water, controlling the ratio of pure water to rhenium-containing loaded organic phase to be (2-10):1, to obtain a pure loaded organic phase; Step 5, a stripping process, stripping the pure loaded organic phase obtained in step 4 with aqueous ammonia, controlling the ratio of aqueous ammonia to the pure loaded organic phase to be (0.5-5):1, obtaining a rhenium-containing stripping solution, thereby achieving the purpose of removing impurities and enriching and recovering rhenium.

2. A method for recovering rhenium from an alkaline rhenium-containing solution according to claim 1, characterized in that: The acid solution added in step 1 is sulfuric acid or a solution containing sulfuric acid.

3. A method for recovering rhenium from an alkaline rhenium-containing solution according to claim 1, characterized in that: The concentration of the aqueous ammonia used in step 5 is (5-20)%.

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