JPS59118893A - Manufacture of electrolytic iron - Google Patents

Abstract

PURPOSE:To reduce extremely the impurity content of electrolytic iron in the manufacture of electrolytic iron using an iron material as an anode and ferrous chloride as an essential component of an electrolytic bath by adding sodium chloride or potassium chloride to the electrolytic bath acidified with hydrochloric acid. CONSTITUTION:An iron material to be used as an anode may be ordinary mild steel, yet pure iron is used so as to increase the purity of electrolytic iron. A bath acidified with hydrochloric acid and contg. ferrous chloride and sodium chloride and/or potassium chloride as essential components is used as an electrolytic bath. The bath is kept at 3.5-4.5, especially 3.8-4.2 pH with sodium hydroxide during electrolysis. The temp. of the bath is adjusted to 65-90 deg.C especially 70-80 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing electrolytic iron using a hydrochloric acid acidic bath containing ferrous chloride, sodium chloride and/or chloridizing power IJ i as an electrolytic bath.

Electrolytic iron contains far fewer impurities than ordinary mild steel, so it can be used as a magnetic material, electronic material, and alloy material.

It has been awarded in fields that require high quality, such as base metal materials for testing and research.

However, with recent technological innovations, ultra-high purity and ultra-low content of specific elements are becoming desirable in special fields. is ammonium sulfate or ammonium chloride.

its pI-1 buffering properties, high conductivity, and stabilizing properties that prevent bath changes due to oxidation of ferrous ions to ferric ions;
At present, electrolytic iron has been specially designed in view of the uniformity of the structure of the inner and outer layers.

However, when these bath components are used, as shown in Table 1, even if pure iron is used as the anode, the content of each component element is
Compared to general mild steel, the decrease is not as great and is relatively high (,
This is unsatisfactory for the field of demand that requires reduction of each component element, and technical improvements have been desired.

Table 1 (Unit: Weight) Here each element was analyzed using the following method (the same applies below) C: Combustion-infrared absorption method S: Same as above P: Molybdenum r Absorbance method Si: Same as above 40: Atomic absorption spectrophotometry (2u: Same as above N: Distillation-indophenol absorption 4 degree method Here, pure iron is obtained by electrolyzing general mild steel once using a conventional method (frV) and refining it using a dry method. It is.

As a result of intensive research into reducing the content of each element, the present inventors found that by adding sodium chloride and/or potassium chloride as a supporting electrolyte to an acidic hydrochloric acid bath containing ferrous chloride, the content of each element can be reduced significantly compared to conventional methods. We succeeded in obtaining electrolytic iron with an extremely low impurity content, and completed the present invention.

That is, 1. The gist of the present invention is a method for producing electrolytic iron in which an iron material is used as an anode and ferrous chloride is the main component of the electrolytic bath. It is in the manufacturing method.

Hereinafter, the content of the present invention will be explained in more detail.

The iron material used as the anode may be general mild steel, but pure iron may be used for the purpose of increasing the purity even a little. The cathode is one on which electrolytic iron is electrodeposited by discharge, and a plate-shaped body made of stainless steel or the like or a rotating drum is used as in the conventional method.

The electrolytic bath is a hydrochloric acid acidic bath containing ferrous chloride, sodium chloride, and/or potassium chloride as main components (with a concentration of 0.5 to 1.5 mol/min of ferrous chloride). l
Preferably fL (u% 0.8-1.2 mol #, jA sodium and/or potassium chloride is preferably adjusted and maintained at 2-4 mol/l [7).

If these components are outside the above range, the bath stability will decrease and f! : It is undesirable because it causes poor electrical conductivity and reduces the yield of homogeneous electrolytic iron.

The strength of the bath is that the bath is a hydrochloric acid bath, which is acidic, but 3
5-4.5 preferably 3.8-4.2 is the bath stability (F
(e) stability) is selected in terms of the homogeneity of the product electrolytic iron.

The bath temperature is selected to be 65 to 90°C, preferably 7o to 80°C for the same reason as in the case of PL.

The present invention will be explained below in terms of implementation.

Example 1 Anode cage 11 and pure iron were used, respectively, and a stainless steel rotating drum was used as the labia.

The electrolytic bath conditions were FeC40,9-1. O mol/IIc hydrochloric acid bath) NaC
13 mol/12 (hydrochloric acid bath) pH 4.1 to 4.2 Bath temperature 70 to 75°C Voltage 3.5 V Current density 2.5 A/dttl maintained at 0 Impurities contained in electrolytic iron not obtained as a result of electrolysis Analyze the second
Each element is shown in the table.

Example 2 The same conditions as in Example 1 were repeated except that KCA was used instead of NaCl. The results are shown in Table 3.

Table 3 (Unit: Weight) Example 3 The same conditions as in Example 1 were repeated except that L/2 of the number of moles of NaC7 was replaced with KCl.

The results are shown in Table 4.

Table 4 (Unit duplex weight ratio) As is clear from the results of the above examples, it was found that the impurity content could be extremely reduced by using the electrolytic bath of the present invention.

Patent applicant: Showa Denko Co., Ltd. Agent Sei Kikuchi

Claims (3)

[Claims] (1) In the manufacturing method of electrolytic iron in which iron material is used as an anode and ferrous chloride is the main component of the electrolytic bath, chlorination is carried out in a hydrochloric acid acidic electrolytic bath)
A method for producing electrolytic iron, characterized by adding IJium and/or potassium chloride. (2) PII f of the electrolytic bath: The method for producing electrolytic iron according to claim 1, which is carried out while maintaining the PII f at 35 to 45 using hydrochloric acid and caustic soda. (3) The method for producing electrolytic iron according to claim 1 or 2, which is carried out while maintaining the temperature of the electrolytic bath at 65 to 95°C.