Disclosure of Invention
In view of the deficiencies in the prior art, it is an object of the present invention to address one or more of the problems in the prior art as set forth above. For example, an object of the present invention is to provide a method and an apparatus for electrolytic reduction of a metal sulfide, which are simple in process and environmentally friendly.
In order to achieve the above object, an aspect of the present invention provides a method for electrolytically reducing a metal sulfide, which may include reducing the metal sulfide in an electrolytic cell including an electrolytic bath for loading an electrolytic solution, the metal sulfide to be reduced, a conductive support capable of being loaded with the metal sulfide, an anode conductive extension disposed above the conductive support opposite the conductive support, and a cathode bar connected to the conductive support and an anode bar connected to the anode conductive extension, the cathode bar being connected to a cathode, the anode bar being connected to an anode, the method further including the steps of: placing the conductive carrier loaded with the metal sulfide and the anode conductive expansion piece into an electrolyte; controlling the temperature of the electrolyte, adjusting the relative distance between the conductive carrier and the anode conductive expanding piece, continuously stirring the electrolyte, and electrolyzing under the condition that the cell voltage is 1.8V-3.0V to complete the electrolytic reduction of the metal sulfide.
In an exemplary embodiment of the method for electrolytically reducing a metal sulfide of the present invention, the control electrolyte temperature may be 40 to 80 ℃.
In one exemplary embodiment of the method for electrolytically reducing a metal sulfide of the present invention, the conductive support may be at a relative distance of 1cm to 30cm from the anode conductive extension.
In an exemplary embodiment of the method for electrolytically reducing a metal sulfide of the present invention, the stirring rate may be 80r/min to 500 r/min.
In one exemplary embodiment of the method of electrolytically reducing a metal sulfide of the present invention, the electrically conductive support may be a graphite container and the anode electrically conductive enlargement may be a graphite block.
In one exemplary embodiment of the method for electrolytically reducing a metal sulfide of the present invention, the electrolyte may be a eutectic solvent.
In one exemplary embodiment of the electrolytic reduction method of the present invention, the metal sulfide may be antimony sulfide, cuprous sulfide, zinc sulfide, lead sulfide, and tin sulfide.
In one exemplary embodiment of the method of electrolytically reducing a metal sulfide of the present invention, the metal sulfide may be in a powdery or lump form.
Another aspect of the present invention provides an apparatus for electrolytically reducing a metal sulfide, the apparatus may include an electrolytic bath for holding an electrolyte, a cathode member, an anode member, and a stirring member; the cathode component comprises a conductive carrier capable of containing metal sulfide and a cathode bar, wherein one end of the cathode bar is connected with the conductive carrier, and the other end of the cathode bar is connected with a cathode; the anode component comprises an anode conductive expanding piece and an anode rod, the anode conductive expanding piece is arranged opposite to the conductive carrier and is arranged above the conductive carrier, one end of the anode rod is connected with the anode conductive expanding piece, and the other end of the anode rod is connected with the anode; the stirring piece is arranged in the electrolyte and can stir the electrolyte.
In one exemplary embodiment of the apparatus for the electrolytic reduction of metal sulfides of the present invention, the electrically conductive support may be a graphite container and the anode conductive extension may be a graphite block.
Compared with the prior art, the method for electrolytically reducing the metal sulfide is simple, has high metal yield, can realize the separation of metal and sulfur, and eliminates SO2The gas is discharged, the environment is friendly, the process is simple, the structure of the electrolysis device is simple, and the industrial production can be realized.
Detailed Description
Hereinafter, the method and apparatus for electrolytically reducing a metal sulfide according to the present invention will be described in detail with reference to the accompanying drawings and exemplary embodiments.
Specifically, the self-designed electrolysis device is combined with electrolysis process parameters, a power supply is switched on after the metal sulfide is contained in the conductive carrier, the metal sulfide can be efficiently electrolyzed and reduced, the reduced metal is placed in the conductive carrier of the electrolysis device after electrolytic reduction, elemental sulfur in the metal sulfide exists in electrolyte, the metal and the sulfur can be well separated through filtration, the emission of sulfur dioxide gas can be avoided, the environmental pollution cannot be caused, and the metal recovery rate is high.
FIG. 1 shows a schematic view of an apparatus for electrolytically reducing a metal sulfide in accordance with an exemplary embodiment of the present invention.
In one aspect, the invention provides a method for electrolytically reducing a metal sulfide. In one exemplary embodiment of the method for electrolytically reducing a metal sulfide of the present invention, the electrolytic method may reduce the metal sulfide in an electrolytic cell including an electrolytic cell loaded with an electrolyte, the metal sulfide to be reduced, a conductive support capable of being loaded with the metal sulfide, an anode conductive extension disposed above the conductive support opposite the conductive support, and a cathode bar connected to the conductive support and an anode bar connected to the anode conductive extension, the cathode bar being connected to a cathode, the anode bar being connected to an anode, the method may further include the steps of: placing the conductive carrier loaded with the metal sulfide and the anode conductive expansion piece into an electrolyte; controlling the temperature of the electrolyte, adjusting the relative distance between the conductive carrier and the anode conductive expanding piece, continuously stirring the electrolyte, and electrolyzing under the condition that the cell voltage is 1.8V-3.0V to complete the electrolytic reduction of the metal sulfide.
In this embodiment, the metal sulfide may be antimony sulfide, lead sulfide, or tin sulfide. Of course, the metal sulfide of the present invention is not limited thereto, and for example, the metal sulfide may be copper sulfide, cuprous sulfide, zinc sulfide, nickel sulfide. The metal sulfide may be in powder form or in bulk form. Preferably, the metal sulfide is powdery, but the powder is not too small, and the powdery metal sulfide is required to be settled as much as possible and not to float due to stirring. Thus, the contact with the conductive carrier is good, and the conductivity is good. The floating powder causes poor contact. The block shape has larger volume, which is not beneficial to the thorough electrolysis and the electrolysis speed.
In this embodiment, the electrolyte may be an ionic liquid. For example, the ionic liquid may be a eutectic solvent, which may include choline chloride-ethylene glycol, choline chloride-urea, choline chloride-malonic acid, choline chloride-thiourea, betaine-hydrochloride. Preferably, the electrolyte capable of dissolving the elemental sulfur is better, so that the elemental sulfur and the elemental metal can be directly separated, and filtering separation is needed. Of course, the method of the present invention is not limited thereto, and the solvent may be selected so long as the decomposition voltage of the solvent is greater than the voltage required for the electrolyzed metal sulfide.
In this embodiment, the temperature of the electrolyte may be controlled to be 40 ℃ to 80 ℃. Preferably, the temperature of the electrolyte may be controlled to be 50 ℃ to 75 ℃, for example, 62 ℃.
In this embodiment, since the electrolyte has a certain resistance, if the relative distance between the conductive carrier and the anode conductive expansion element is relatively long, the conduction between the currents is not facilitated, and the metal sulfide cannot be electrolyzed; if the distance is short, a path may be formed between the cathode bar and the anode bar, resulting in poor electrolysis. Thus, the relative distance between the conductive support and the anode conductive extension plays an important role in the electrolysis of the metal sulfide. The relative distance between the conductive carrier and the anode conductive expanding piece can be 1 cm-30 cm, preferably, the relative distance can be 5 cm-20 cm, for example, 15 cm. The conductive carrier is disposed opposite the anode conductive extension, preferably, the anode conductive extension is disposed directly above the conductive carrier, which facilitates the conduction of current.
In the present embodiment, the stirring rate is 80r/min to 500 r/min. The electrolyte may be stirred manually or mechanically. For example, a stirring paddle may be placed for stirring, and for example, a stirrer may be placed at the bottom of the electrolytic bath and stirred by magnetic force. The rate of agitation has an important influence on the efficiency of the electrolytic reduction of the metal sulfide and the reduction rate. On the one hand, stirring can promote mass transfer; on the other hand, the stirring can promote the reduced product sulfur to enter the solution and be dissolved in the electrolyte, and the property of selective dissolution (such as eutectic solvent) of the electrolyte is well utilized to realize the complete separation of the sulfur and the metal. The stirring speed is too high, so that sulfide floats, the contact with a conductive carrier is influenced, and the reduction speed is reduced; the stirring speed is too slow, which is not beneficial to the transmission of anions and cations in the electrolyte, and the diffusion becomes a limiting link of the reaction and influences the reduction speed.
In the present embodiment, the electrolysis time may be 2 hours to 30 hours, but the electrolysis time of the present invention is not limited thereto, and may be an empirical value or determined according to actual conditions on site.
In this embodiment, the conductive carrier may be a container having good conductivity and stable properties. I.e. no reaction takes place in the electrolyte. For example, preferably, the conductive support may be a graphite container. The anode conductive extension is an inert electrode with good conductivity, such as, preferably, a graphite block. The graphite block can be provided with holes uniformly distributed on the surface of the graphite block, which is beneficial to the flow of electrolyte. The graphite block may be a graphite disk.
In the present embodiment, the electrolytic cell may be any container, and for example, the electrolytic cell may be a glass container, a graphite container, a cement container, or the like.
As described above, the electrolytic apparatus used in the method for electrolytically reducing a metal sulfide of the present invention can reduce a metal sulfide by the electrolytic reduction metal sulfide apparatus described below.
Another aspect of the present invention provides an apparatus for electrolytically reducing a metal sulfide, which, in one exemplary embodiment of the apparatus for electrolytically reducing a metal sulfide of the present invention, as shown in fig. 1, includes an electrolytic bath 1, a cathode member 2, an anode member 3, and a stirring member 4. Wherein the electrolytic cell 1 is used for loading an electrolyte. The electrolyte is an electrolyte that can electrolyze a metal sulfide, and for example, the electrolyte may be an ionic liquid. The cathode member 2 includes a conductive support 21 capable of supporting a metal sulfide and a cathode rod 22. One end of the cathode bar 22 is connected to the conductive carrier 21, and the other end is connected to a cathode of a power supply device.
The anode member 3 includes an anode conductive extension 31 and an anode rod 32. The anode conductive expanding piece 31 is arranged opposite to the conductive carrier 21 and above the conductive carrier 21, one end of the anode rod 32 is connected with the anode conductive expanding piece 31, and the other end is connected with an anode of a power supply device. Preferably, the anode conductive expansion element 31 is disposed directly above the conductive carrier 21.
The stirring member 4 is placed in the electrolyte and can stir the electrolyte. FIG. 1 shows a magnetic stirring apparatus according to an embodiment of the present invention.
In this embodiment, the relative distance between the conductive carrier and the anode conductive expanding member may be 1cm to 30cm, preferably, the relative distance may be 5cm to 20cm, for example, 15 cm.
In this embodiment, the conductive carrier may be a container having good conductivity and stable properties, for example, preferably, the conductive carrier may be a graphite container. The anode conductive extension is an inert electrode, for example, preferably, a graphite block. The graphite block can be provided with holes uniformly distributed on the surface of the graphite block, which is beneficial to the flow of electrolyte. The graphite block may be a graphite disk.
In this embodiment, the stirring member may be a stirring paddle or a magnetic stirrer. Of course, the stirrer of the present invention is not limited thereto, and other stirrers capable of stirring the electrolyte may be used.
In the present embodiment, the electrolytic cell may be any container, and for example, the electrolytic cell may be a glass container, a graphite container, a cement container, or the like.
In this embodiment, in order to enable faster electrolysis of the metal sulphide, the metal sulphide may be heated, for example, the apparatus for electrolytically reducing the metal sulphide may comprise a heating apparatus. The heating means may be as shown in fig. 1, and the heating means may include an oil bath heating means 5, heating using an oil bath. Of course, the heating method of the present invention is not limited thereto.
In conclusion, the method is simple, the metal yield is high, the separation of metal and sulfur can be realized, the environment is friendly, the process is simple, the structure of the electrolysis device is simple, and the industrial production can be realized.
Although the present invention has been described above in connection with exemplary embodiments, it will be apparent to those skilled in the art that various modifications and changes may be made to the exemplary embodiments of the present invention without departing from the spirit and scope of the invention as defined in the appended claims.