JPS62161989A - Method for recovering bismuth and/or mercury - Google Patents

Abstract

PURPOSE:To efficiently recover bismuth and mercury in a hydrochloric acid bath by blowing H2S and H2C2O4 into the bath and carrying out electrolysis. CONSTITUTION:When bismuth and/or mercury in a hydrochloric acid bath is recovered, H2S and/or H2C2O4 is blown into the bath and electrolysis is carried out. At this time, the hydrochloric acid bath is prepd. as a bath acidified with hydrochloric acid to >=about 1N, a carbon electrode or the like is used as the anode and a copper plate as the cathode. H2S and/or H2C2O4 is preferably blown into the bath on the anode side. The amount of H2C2O4 blown is about 1.0-1.7 times the reaction equiv. and H2S is blown to such a degree that the electrolytic soln. is not impregnated with the odor of Cl2. The current density is about 30-250A/dm<2> and the temp. of the electrolytic soln. is ordinary temp. Thus, bismuth and/or mercury can be efficiently recovered.

Description

[Detailed description of the invention] 1 匪π1 匮 The present invention relates to a method for recovering bismuth and/or mercury.

Bismuth can be easily recovered using conventional bismuth and/or mercury recovery methods.
There was no way to recover mercury from the liquid.

For this purpose, the metals adsorbed on the ion exchange resin or Kire-1 resin are eluted with an acidic solution such as hydrochloric acid.

In the method for recovering the target metal, it is preferable to recycle the solution, but since there was no suitable recovery method, problems have arisen in cases where bismuth remains concentrated in the recycled solution. That is, in a method for recovering rhenium, antimony, etc., if bismuth is concentrated in the liquid, the adsorption performance of the ion exchange resin deteriorates, making it impossible to perform a preferable recovery process.

Therefore, there has been a need for a preferable method for recovering bismuth and/or mercury out of the system.

Furthermore, the present invention is not limited to the above cases, but
This is a method for efficiently recovering bismuth and/or mercury in liquid.

A method for recovering bismuth and/or mercury in which 1 (2S and/or H2C, O) is blown into a bismuth and/or mercury-containing solution and electrolysis is carried out. It provides:

The solution targeted by the present invention is a hydrochloric acid acid bath (1N or more).
It is. The concentrations of bismuth and mercury are not particularly limited. For example, in a method of recovering rhenium using an ion exchange resin, the eluent is made acidic with hydrochloric acid, and rhenium is eluted and recovered.In this case, when recycled, 1 to 5 g#l of bismuth and 0.07 to 0.0 g/l are recovered. 04gIQ of mercury accumulates.

When processing such a liquid, an insoluble anode, for example, is used as the anode. For example, it is a carbon electrode. Furthermore, a copper plate, for example, is used as the cathode.

The addition of [12S and/or H, C, O,] in the present invention is as follows.

It is preferable to add it to the anode side. This is because - the C12 gas generated at the anode by electrolysis is dissolved on the anode surface by the 0-type reaction, and the Bi deposited on the cathode is dissolved by the 00-type reaction, resulting in a decrease in the recovery rate of Bi.
It is believed that by adding a reducing agent such as H2S and 11□C2O4, the recovery rate of Bi can be greatly increased by decomposing HCl0 by the 00-type reaction.

C12+8,0→)ICI+HCl0
・・・・・・■311CIO+ 2Bi −+ Bi,
O1+ 311C1...■Bi, 0. +
611C1→2BiC1,+3H,O・・・・・・■
HCl0+11. S-+l+C1+S' +l+, 0
・・・・・・■11cIO+ 11. C2O4
→HCI + 2CO2+H□0・・・・・・■H,S
and or 112c20. The amount of blowing is ! I,C
For 20°, it is preferable to blow about 1.0 to 1.7 times the amount of one reaction equivalent, and for H and S, it is preferable to blow in so that the C12 odor does not attach to the electrolytic solution.

The electrolytic conditions are preferably such that the current density is 30 to 250 A/I, and the electrolytic solution temperature is room temperature 1, etc.

Effects of the Invention By implementing the present invention as described above, the following effects can be obtained.

(1) Bismuth and/or mercury in the solution can be efficiently recovered.

(2) Bismuth, mercury, etc. can be efficiently recovered from the hydrochloric acid acidic eluent that is recycled in the rhenium recovery process.

(3) From the hydrochloric acid acidic eluent that is recycled in the process of removing sb, etc. using a chelate resin of copper electrolyte.

Bismuth and/or mercury can be efficiently recovered.

(4) The eluent does not accumulate harmful components and can be used repeatedly.

1.5 times the reaction equivalent of H2C, 04, H, and S were each added to a hydrochloric acid solution containing bismuth and treated under four conditions. As a result, bismuth was efficiently recovered as shown in Table 2.

The bismuth in the stock solution was 3.5 to 3.66 g/fi as a sample, and the bismuth in the solution after about 22 hours was as follows.

Efficient recovery of 0.93 to 0.12 g/fi was achieved. In particular, those to which H and S were added showed a high bismuth recovery rate.

Similarly, the recovery rate of mercury also showed a high value.

Margin Comparative Example 1 Below, under the same conditions as Example 1, H, C20, and H, S
As shown in Table 9, the bismuth recovery rate was poor even after 22 hours.

Margin below

Claims (1)

[Claims] (1) A method for recovering bismuth and/or mercury in a hydrochloric acid bath, characterized in that H_2S and/or H_2C_2O_4 is blown into a liquid containing bismuth and/or mercury to perform electrolysis.