JPS61295385A - Anode system comprising elongated sintered titanium piece inelectrolytic cell for anodic precipitation of electrolytic brown stone - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides a method in which an anode system is suspended between two flat cathodes, in which case the longitudinal axis of the sintered titanium strip is aligned with the anode system. The present invention relates to an anode system consisting of a sintered titanium strip in a remission bath for electrolytic brownstone t-anodic deposition, which lies in the plane of .

Conventional technology For several years, titanium has been produced using electrolytic brownstone (electrolytic manganese dioxide = E
Unatsutomo is gradually attracting attention as an anode material when manufacturing MD). This is because titanium does not show wear phenomena compared to the frequently used graphite, and compared to the similarly used lead it does not actually corrode and can therefore be used repeatedly. .

A particular drawback of titanium is that it has a tendency to passivate during anodic loading, i.e. at a constant current density, a layer of poorly conducting oxide forms on its surface. This tends to cause an increase in terminal voltage. However, electrolytes containing manganese ions form a highly conductive coating of titanium due to the cap, so that even at high electrolytic densities, which are possible in manganese-free electrolytes, such as dilute sulfuric acid, the terminal voltage does not increase. However, the heat absorption by the EVD layer is not perfect, so the titanium anode can become cine-like under certain conditions. Such phenomena have been extensively described, and it has been shown that, in addition to current density, sulfuric acid concentration and temperature also play an important role as limiting barometers for the solution. Ghamie-Ingsnie
ur-Technik) Volume 49, Page 347 (1
977) (see British Patent No. 977569).

Many attempts have been made to overcome such electrolytic limitations. This also includes the provision of an active layer on the titanium surface at high cost in order to avoid passivation, thus ensuring high current densities and thus high economic efficiency of the existing equipment.

One important method is to enlarge the effective table 11 of the electrodes and thus reduce the true current density for a given sliding current strength.

It has therefore been proposed to roughen the titanium surface by sandblasting and thus to increase it, thereby at the same time achieving good adhesion of the deposited EMD coating on the surface (US Pat. No. 3,436,323). Attempts have also been made to achieve the same objective using expanded metal (US Pat. No. 3,654,102).

Already in 1952 and in 1953, it became known that an anode made of titanium sintered in a manganese sulfate bath (a titanium thin plate) also allowed a high current density (
U.S. Patent No. 2,608,531 and U.S. Patent No. 26+11
No. 15 Specification Lu). Nevertheless, sintered titanium was not used in practice for a long time in the manufacture of goods, probably due to technical difficulties. In 1976 I#-, an industrial electrode based on I sintered titanium was first described (Nishitoi, Japan Patent Publication No. 1 2644:1414, Akira ml). At the same manufacturing cost, this electrode could be made using thin titanium. The boardwork 9 is also quite rigid.

Currently, there is a trend in EMD manufacturing to use even lower current densities, so the activation of titanium and the use of large W# pole surfaces are less important. 1st annual of metalless
Metals) Volume 434 (1982), No. 67~
The mechanical and electrical properties of sintered titanium, which for technical reasons are produced in the form of plates, are described on page 441, and the mechanical and electrical properties of sintered titanium are determined by the method, which for technical reasons is produced in the form of sheets of rolled titanium or solid titanium plates. Rainbow is also an important anode material. That's because
This is because, for the same cost, a thicker anode (L#) can be manufactured in kW and at the same time a surface roughness advantageous for the adhesion of EMD to be deposited is obtained.

! Previously known forms of the second anode are plates made of graphite or titanium, or rods or tubes made of expanded titanium or sintered titanium or graphite. West German Patent Application Publication No. 285
No. 6820).

An anode consisting of two titanium sheets has also been proposed. By grooving these two thin titanium plates, they are made into a corrugated shape.
Anodes have also been proposed in which the anodes are bath-welded together, 9 thus resulting in tubes clamped together by webs. This provides good rigidity of the υ anode.

Two practical demands must always be made on anodes for producing EMD.

a) good adhesion during electrolysis b) easy separation of the KMD after 11 dissolution These two requirements are mutually exclusive, so a compromise is necessary. EMD coatings are easily removed from flat-surfaced anodes by hammer impact, and the adhesion of the coating to the anode is deceptively poor. The smaller the diameter, the better the substrate for the attachment of the tube method (EMf), in which the crystals can grow freely from all sides. However, since these tubes are placed at a small distance from each other, the E.M.
Since D also grows into the gap, EMD i is taken from here.
If it is released, it can only be removed with great effort. In the case of deformable lead anodes this is not a problem, but if the anode component is rigid and fixed]
Removal of 1iVD is a laborious process.

Problems to be Solved by the Invention The object of the present invention is to combine the advantages of good adhesion during electrolysis and its easy peelability by using sintered titanium as a main material in a tank with a large anode area. The object of the present invention was to provide a titanium anode which can be loaded into a volume and which combines in such a way that the advantages of sintered titanium compared to solid titanium are fully exploited.

Means for solving the problem This problem was solved by using a sintered metal plate with dimensions a, instead of a wide sintered metal plate.
b, a narrow sintered titanium strip of L (a=width, b=thickness, and L=length), with the longitudinal axis of the strip lying in the longitudinal direction of the main plane of the anode, and the longitudinal axis of the strip A constant mounting from the central electrode main plane was solved by arranging it to pivot by an angle α. This installation has angles between 10 and 90.

The strips may lie parallel to each other or at an angle to each other; in the latter case, the mounting is done so that the corners alternate at α
and 180 −α. Advantageously, the strips should not touch each other, but should maintain a mutual distance of *1. Although it is advantageous to fix the strip in its length in a suspension structure from the top to the bottom, the invention also includes a 90-swiveled arrangement, i.e. an arrangement in which the strip is fixed horizontally into the container. is within the range of

In particular, the present invention provides anodically deposited electrolytic stones, in which the anode system is suspended between two flat cathodes, respectively, and the longitudinal axis of the sintered titanium strip lies in the plane of the anode system. Regarding an anode system consisting of sintered titanium strips in an electrolytic cell for
It is characterized in that the sintered titanium strips pivot about their longitudinal axis outwards from the plane of the anode system and through an angle α between 10 and 9° with this plane.

Furthermore, the anode system according to the invention is selectively and advantageously characterized by: a) sintered titanium strips arranged parallel to each other, measured by the projection of the strips onto the plane of the anode system; and the distance d between the sintered titanium strips is 0; 0; or 〉0; b) the sintered titanium strips alternately enclose angles α and 18o−α with the plane of the anode system in a zigzag arrangement; and the distance 4 between the sintered titanium strips, measured by projection of the strips onto the plane of the anode system, is >0; C) the angle α is between 30 and 70: d) the sintered titanium strips The width of the electrode is twice as large as its thickness, but it is also smaller than half the distance between the cathodes.

EXAMPLES Next, an anode system according to the present invention will be described in detail with reference to examples shown in the accompanying drawings.

FIG. 1 shows the sintered titanium strips 1 of the anode system arranged in a zigzag manner between two flat cathodes 2Q, which sintered titanium strips 1 are arranged at alternating angles α or 180 from the plane 3 of the anode system. It is turning outward by −α.

FIG. 2 shows a sintered titanium strip 1 of the anode system arranged parallel to two flat cathodes 2°, which sintered titanium strip 1 extends outwardly from the plane 3 of the anode system by an angle α. It's circling.

FIG. 3 shows two sintered titanium strips as a partial view from FIG. 1. FIG. In this case a=width of the strip; b=thickness of the strip; d=distance between the strips in their projection onto the plane of the anode system. The angle β between the strip edge a and the strip diagonal is important in the following equation. Figure 3 is d
〉0 is shown.

FIG. 4 shows two sintered titanium strips as a partial view from FIG. 2 for the case d<0.

The width and angle α of the strips and the number of strips per anode system υ depend respectively on the electrolyzer dimensions present and the desired total current load of the anode system. Below, if the dimensions of the strip are given, the thickness D and the effective surface area of the anode system (Oaf), then the effective surface area of the anode system (0ef
f) Write the formula by which the ratio (Q) of the formal surface area (OfOrm) can be calculated as a function of the angle α.

However, on the contrary, from the line diagram created according to these formulas,
It is also possible to know at least how large the angle α has to be chosen if one wants to obtain a certain effective surface area of the anode system.

n = Hajime "Adventure 5in (α + β) (■) Ooff ==
n · (a + b) −L −2 (1) (n = number of strips per anode system; a = @ of the strips; b = thickness of the strips; 1 = length of the strips; d = distance between the strips in their projection onto the plane of the anode system; B = width of the anode system)
.

The maximum thickness D) of the rainbow anode system is determined by the usable distance between the cathodes in the electrolytic cell, and within this maximum thickness,
The thickness of the HMD deposit and the minimum distance of the electrodeposited anode system from the flat cathode are added. Furthermore, D is a function of the width of the strip (- and the angle α, and also the thickness of the strip b) and the angle β [see equation (If) and FIG. 3].

It is demonstrated that the anode system according to the invention is also superior in planar arrangement. This is because the additional anode iii[+
More than 100% of the product can be accommodated in the electrolytic cell,
Moreover, the geometry of the arrangement induces good adhesion of EMD on the anode system.

Example 1 I of zigzag arrangement of sintered titanium strips for anode system
Ig(a) = 4 an strip thickness b) = 0.
8cm Distance between strips (d) = 0.2cm Formal width of anode system: 100σ, Formal length of anode system: 1
00crn, formal surfaces on both sides of the anode system n = number of strips per anode system, D = thickness of the anode system Table 1 α! L D Q(off) Q (angle) (my) (m2)10 22
1.48 2,11 1.0620 222.12 2
,111.0630 232.69 2,211.10
40 253.18 2,401.2050 27 3
．． 58 2,591.3055 293.74 2,7
81.3960 323, &S 3.031.546
5 353.96 3,361.6870 394.0
3 3,741.8775 45 4.07
4,32 2.1680 53 4.08
5.09 2.54 (90834,007,97
3,94) Table 1 shows that outward pivoting up to α = 20 is due to the planar arrangement of the sintered titanium strips (α = O−) when the distance between the strips (d) = , 2xx. Comparisons indicate that the technology does not offer any significant benefits. The reason for this is that the gaps between the strips are quickly bridged by the EMD, so that the anode system continues to work like a planar anode system, which in this case is under internal stress. On the other hand, α=7
Turning outward by more than 0 is also disadvantageous. This is because the gaps between the strips become smaller and smaller, so that the EM
This is because it becomes increasingly difficult to remove D from it, and finally, at α=90, the zigdeck shape is abandoned and an unreasonably thick anode, which is, as it were, plane again, is obtained. Therefore, from the plane of the anode system, the optimal rotation angle α of the sintered titanium strip about its longitudinal axis from the plane of the anode system
=30-70 or alternately 150-110. Table 1 also shows that the thickness of the anode system is approximately 70 to 90 mm.
It shows that it exceeds 4 Confucius in the angular range under construction. This is because the diagonal width of the sintered titanium strip plays a role here.

Example 2 The diagonal parallel arrangement dimensions of the anodic Q sintered titanium strips are the same as in Example 1 with the following exceptions.

Width of strip (a) = 3 cm, thickness of strip (b) = O
', 6 cat% Distance between strips (a) = 0 Table 2 10 32 1.11 2,30 1.152
0 33 1.59 2,38 1.1930
34 2.02 2.45 1.2240
37 2.39 2,66 1.3350
41 2.68 2,96 1.4855 4
5 2.80 3,24 1.6260 49
2.90 3,53 1.7665 55
2.97 3,96 1.987! :i 73
3,05 5,26 2.63 If the need for effective surface rams is small, the number n can of course be lowered. That is, it is possible to increase the distance pressure in the fMJ polar system and arrange a small number of strips.

[Brief explanation of the drawing]

The attached drawings show embodiments of the anode system of the present invention.
The figure is a plan view of an anode system in which sintered titanium strips are arranged in a zigdek pattern between two flat cathodes. Figure 2 shows a parallel sintered titanium strip between two flat cathodes. FIG. 3 is a partial view from FIG. 1 for 1>0, showing two sintered strips;
The figure also shows two sintered strips (a partial view from FIG. 2 in the case of 1<0). 1... sintered titanium strip, 2... cathode, 3... anode Plane of the system, a... Width of the strip, b... Thickness of the strip, d... Distance between the strips when projected onto the plane of the anode system, D = Anode system thickness.

Claims (1)

[Claims] 1. Anodic deposition of electrolytic brownstone, in which the anode system is suspended between two flat cathodes in each case, and the longitudinal axis of the sintered titanium strip lies in the plane of the anode system. In an anode system consisting of a sintered titanium strip in an electrolytic cell for the purpose of sintering, the sintered titanium strip pivots outward from the plane of the anode system about its longitudinal axis and lies between 10 and 90 degrees with this plane. An anode system consisting of a sintered titanium strip in an electrolytic cell for anodic deposition of electrolytic brownstone, characterized by turning an angle α between. 2. The anode system according to claim 1, wherein the sintered titanium strips are arranged parallel to each other. 3. An anode system according to claim 2, wherein the distance d between the sintered titanium strips, measured by projection of the strips onto the plane of the anode thread, is <0;0; or >0. 4. An anode system according to claim 1, wherein the sintered titanium strips surround the plane of the anode system alternately at angles .alpha. and 180-.alpha. in a zigzag arrangement. 5. An anode system according to claim 4, wherein the distance d between the sintered titanium strips, measured by projection of the strips onto the plane of the anode system, is ≧0. 6. The anode system according to any one of claims 1 to 5, wherein the angle α is between 30 and 70°. 7. Any one of claims 1 to 6, wherein the width of the sintered titanium strip is more than twice its thickness but less than half the cathode-to-cathode distance. Anode system described in section.