US1444887A - Method of producing pure iron by electrolysis - Google Patents

Description

Patented Feb. 13, 1923.

onrrao STATES PATENT orrica.

AUGUST scnwmrn, or FRANKFORT-ON-THE-MAIN, GERMANY, as'sronon TO THE FIRM: CHEMISCHE FABRIK GRIESHEIM-ELEKTRON of FRANKFORT-ON-THE- MAIN, GERMANY.

METHOD OF PRODUCING PURE IRON BY ELECTROLYSIS.

No Drawing.

T 0 all 1071 0122. it may concern:

Be it known that I, Aoeus'r Sonwm'ru, a

citizen of Germany, residing at 1*rankfort-.

on-the-Main, Germany, have invented certain new and useful Improvements in Methods of Producing Pure Iron by lllectrolysis, of which the following is a specification.

My invention refers to the production of pure iron by electrolysis, more especially from solutions of ferrous chlorides, and its 4 particular object is to improve the methods hitherto employed to this end.

It is old to produce pure iron by electrolysis from a pure solution of ferrous chloride at a temperature of 70 C. However, this method is of no value from a. technical point of View inasmuch as it is impossible to obtain a commercial product from the neutral vigorously stirred electrolyte. Soon after the process is started precipitates containing oxide will settle down.

It has further been proposed to employ as electrolytes neutral iron salts to which slightly dissociated inorganic or organic acids, such as boric acid, acetic acid, citric acid, carbonic acid or the like have been added. All these methods, howeve'r,-yield a very impure iron owing to the fact that along with it carbon, sulphur and phosphorous separate out from the electrolyte and from the anodic iron.

It has further been proposed to add ammonium salts to the iron salt solutions, but in the products obtained with this method an iron containing nitrogen is obtained.

Up till now a pure iron containing not more than 0.03% impurities has only been produced from iron solutions acidulated with highly dissociated acids such as hydro-- chloric acid or sulphuric acid, Thus a very superior product as far as purity is concerned, is obtained from the solutions of hygroscopic ferrous chloride double salts such as FeCl (la'Cl FeCl .NaCl. However, owing to the addition of sodium chloride, calcium chloride and the like, this process involves great technical drawbacks, inasmuch as these additions greatly diminish the solubility of the ferrous chloride and therefore render it very diflicult to 01 tain 1922. Serial No. 564,929.

trolyte containing the highest possible concentration of iron ions. Further drawbacks connected with this process are-caused by the fact that the composition of the electrolyte IS materially changed by the iron of the anode being dissolved, that the percentage of sulphur, phosphorus and manganese in the electrolyte resulting from the iron anode is almost saturated, the temperature being kept at 85 C. and above.

If these conditions are observed, iron plates of the greatest purity and any desired thickness are obtained.

I-wish it to be understood that I do not desire to be limited to the exact proportions and temperatures mentioned above as many obvious modifications will occure to a person skilled in the art.

I claim:

1. The process of producing pure iron by electrolysis, consisting-in causing an electric current'to act on a slightly-acidulated solution of ferrous chloride ata. temperature of not less than 85 C.

y 2. The process of producing pure iron by electrolysis, consisting in causing an electric current to act on a hot, slightly acidulated substantially saturated solution of ferrous chloride.

3. The process of producing pure iron by electrolysis which consists in causing an elec' tric current to act on a hot solution of ferrous chloride containing a small quantity of free hydrochloric acid ranging between onetenth and one-thousandth normal.

In testimony whereof I aflix my signature.