SU1206345A1 - Method of producing fine pulverulent aluminium - Google Patents

Description

The invention relates to the electrolysis of molten media, and more specifically to methods for the electrolysis and refining of titanium to obtain a fine (-0.18 mm) fraction.

The purpose of the invention is to increase the current efficiency of the fine fraction (-0.18 mm).

The goal is achieved by secondary reduction of titanium in the near-electrode layer and its seizure due to the fact that the process is carried out in a potentiostatic mode at - (2.60-2.72) B relative to the reference chloride electrode for a chloride electrolyte containing 3.5 - 5.0% by weight of titanium, when alkali metal is added as a solution of the latter in the electrolyte.

The proposed concentration limit for titanium lower chlorides in the electrolyte is 3.5–5.0 wt.%. Below the proposed limit, the yield of the fraction (-0.18 mm) decreases, and the current output of all fractions falls. Above the proposed strake (more than 5.0 wt.%) The electrolyte is not technological because of its high hygroscopicity.

The proposed limit of settable potentials is characterized by the onset of alkali metal evolution, which is present in the form of a solution in the molten medium in quantities that allow it to be restored in it.

2.72 2.60

2.29

2.41 2.49

2.30 2.40 2.50

(break)

Me

(Pp)

with the capture of powder sediment. The titanium thus obtained is finely dispersed, the current output is.

Example. The experiments were carried out in a three-electrode cell in an atmosphere of purified argon at 750 ° C. Metallic titanium (a sponge and a compact metal) is used as a soluble anode, the cathode is a steel rod, and the reference electrode is a chlorine half cell. All electrodes are placed in a beryllium oxide crucible. The composition of the electrolyte KC1 - NaCI and 3.0 wt.% Titanium in the form of lower chlorides. Anode current density due to the developed surface of the anode does not exceed 0.175 A / cm. The electrolysis is carried out using a potentiostat P10-20. The cathode product, after being removed from the cell, is processed according to a known method, weighed and analyzed for fineness. The results are shown in the table.

The use of the proposed electrolytic method of obtaining fine titanium provides, in comparison with the known, the possibility of an output of a fraction (-0.18 mm) of at least 88% (versus 45% of the known), except that the total current efficiency of all titanium fractions reaches 0.785 g / A- h (in the known 0.6 g / A-h).

0.792 0.785

0.409

88.8 87.9

45,8

0.620 0.538

0.448 0.624 0.734

69.5 60.3

50.2 69.9 82.2

Editor N. Yatsola

Compiled by G. Melnikova

Tehred A. Babinets Proofreader V. But ha

Order 8656/28 Circulation: Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch PPP Patent, Uzhgorod, st. Project, 4

Table continuation

Claims (1)

METHOD FOR PRODUCING FINE TITANIUM, including electrolysis in a molten chloride electrolyte containing lower titanium chlorides, at 745-755 ° C with a soluble titanium anode and anode current density of not higher than 0.175 A / cm ² , characterized in that, in order to increase current efficiency fine fraction of 0.18 mm, the electrolysis is carried out in a potentiostatic mode with a cathode potential of (2.60-2.72) V relative to the chlorine reference electrode in the electrolyte containing 3.5-5.0 wt.% lower <titanium chlorides.