US1471641A - Electrolytic gas cell - Google Patents

Description

C. F. ADAMS ELECTROLYTIC GAS CELL Filed March 9. '1922 2 Sheets-Sheet 1 @www wv man 0a. 23, 1923. A 1,471,641 UNITED STATI-:s PAT NT OFFICE.

CLARENCE F. ADAMS, OF DAYTON, OHIO.

ELECTBOLYTIC GAS CELL.

Application led vMarch 9, 1922. Serial No. 542,848'.

My invention relates to improvements in` electrolytic gas cells, where a solution is broken up into its component parts and certain parts in the form of gases liberated on metallic collectors and conducted separately or collectively to a suitable storage reservoir and wherein electricityT is the chief agent employed in this operatlon; and 'the objects of my improvements are, Iirst to produce a cell of light Weight construction and of minimum size for economy of space and for portability; second, to give a greater eiciency in production by lowering the resistance tothe passage of current through the solution and the resistance tothe release of gas from the metallic collectors; third, to overcome diiiiculties in the way of internal insulation to the leakage of electricity; and fourth, to provide an automatic back preure equalizer that will also serve as an indicator in quickly giving some idea of comparative volumes of as being generated by each compartment. 'he form and type of this indicator is likewise included within the scope of the invention.

I attain the objects above enumerated by the devices illustrated in the accompanying drawings which constitute a part of this specification and in which Figure 1 is an end View of the assembly showing an exposed end view of the interlor of the left side; Figure 2 isa top view ofthe assembly; Figure 3 is a side view of the assembly showing an exposedside view of a part of the interior construction and Figure 4 is a perspective view of a complete cell; and Figure A5 is a sectional view through the diaphragm with parts of the adjoining boards broken awa 'Ayconsiderable portion of the electrical energy required for the operation of an electrolytic cell is dissipated in the form of heat dueto two principal causes; rst, ohmic resistance of the elements and the electrolyte throu h which the current passes; and secon resistance due to`a polarization of the elemen In overcoming the resistaneesA due to the two above mentioned factors, energy is expended in the form of heat, but it is true that a part of this heat energy is utilized for a useful purpose,

'principally in aiding the chemical association and dissociation that takes place in the electrolyte. This is only carried, however, to a certain point and beyond that oint the heat energy enerated is wasted an lost as far as the eilciency of the operation of the cell is concerned.

Working on the theory that the olariza'- tion of the elements is due princi a ly to the surface tension of the gas bubb es formed Y on the face of the lelements and that this tension increases with the size of the bubble from the time of its inception until the time of its actual release from the element, it was decided to construct a form of element that y would give sucient surface for collecting ions from the solution but present a small surface forl adhesion as the ions rew into bubbles thereby releasing the bubb es before any considerable size could be attained and likewise after the bubbles had been released, provide a clear path through the solution to the upper vsurface of the electrolyte. This problem was viewed from many angles and nally after a number of attempts had been made resulting in various degrees of success and failure, the form and combination illustrated in this specification was adopted.

The cell is built in two principal parts, 10 and 11, Figure 1. Each part consists of a back. pressure regulator and indicator 12, an electrical terminal 13, a transito wood board 14,'transite wood tubes 15, wire coils 16, grid bars 17 and legs 18. The last dev tail of assembly consists of putting the two parts together with bolts 19 as shown in Figure 1, but 2. Just before this assembly is made, however, an asbestos diaphragm 20 and more distinctly dened as in Fig.

a rubber gasket 21 (see Fig. 1) are placed in position as shown. The bolts 19 are then run through the holes traversing the outer border of the' transito boards through the diaphragm 20, the flanges 22 ofthe sheet posing the outer casin drawn up with nuts w by lock washers.

In Fi re 3 is shown a more detailed view of the ack pressure regulator andy indicator. The lower casting 24 thereof carries integral with itself two nipples and two 11.5 elbows whichvhave attached to the vopposite,

The bolts are then ch are held in place packing 21 and the ,Y metal shells 23 coml.

i' action of this seal.

. a nipple,

ends, the combination consisting of nipples 25 and 26, Ts 27'and plugs 28. Two holes. are providedl in the sheet metal shell 23 for the accommodations of the nipples 26 as shown and a non-leakable but flexible 'oint is made between the nipple and shell y the packing combination 29. A cubical glass dome 30 is placed between castings 24 and 31. Rectangular rubber gaskets are placed at the top and bottom ends of the g1obe. The globe with upper and lower castings is then clamped together by means of Studs 32 and wing-nuts 33. The casting 24 is secured to the sheet metal shell 23 by means of machine screws 34 as shown. In the upper casting 31 is tted a nipple 35.

The functioning of the back pressure regulator and indicator is substantially as follows: Water is first introduced through nipple 35 until thelevel indicated by line 36 is reached. Any further water intro` duced would simply overflow through the .pipe combination into the cell.- The water' thus introduced and retained in the combination including the dome 30 is to act as a seal for the gas coming from that part of the cell to which it is attached. Gas

-1s conveyed from the cell through the ipe combinations on both sides of the ome and through the water seal up into the it is then released through nipple 35 to any suitable conveying (system leading to storage or'othcr- Wise. A as invariably carries some moisture as it is conveyed from the cell. This moisture would tend to increase the water level in the pipe and dome combination but this cannot occur for the reason that any surplus created above the line 3e is caused to fall back by virtue of its own weight into the cell from whence it came and where it should remain. This arrangement, therefore, automatically provides against any increase in the depth of the Water seal and lconsequently any increase in the back pressure on the cell due to the Evaporation of the water contained in the dome and pipe com` .bination is more than compensated for bv moisture carried over 'with the gas and consequently the level of the water seal reymainsy vat the same point under all conditions and exerts a constant value in back pressure at all times. Water may be introuced to the cell as needed by removing either one or both of the plugs 28, or by removing either one or both of these plugs, permanent connections may be made from Ts 27 to an overhead water system through l hose and regulating valve (not shown), the rubber hose interposed for electrical insulation purposes and the valve for the purpose of regulating the flow of Water asneeded. Byusing a lass dome in thls combination here referre to as a part nemesi of the back pressure re lator and indicator, a means is provi ed for inspecting at a glance the size and quantity of the gas bubbles as they pass through the water seal into 4the globe. The size and quantity of the gas bubbles is a visual indicator of the internal working conditions lof the cell at all times. The size and capacity of this dome and pipe combination is the same on each side of the cell and the gases coming through each combination is subjected to the same back pressure from the water seals, making a balance of pressure internally of the gases generated on both sides.

In operation direct current electricity is used in connection with two metallic elements immersed inthe solution and between the elements is placed an asbestos diaphragm to keep the gases formed o n each of the elements separated. As was stated before, the cell that represents the subject-matter of this invention, is divided into two principal parts and each part contains separately its own element combination.

The electrode elements in this cell constitute one of the chief novel features of the invention and theirconstruction is substantially as follows: Each electrode element is made up of one transito board, a-number of transite tubes, a number of coils of wire, a metallic grid and an electrical terminal. In the place of using transite board, vulcanized rubber of the proper consistency or any other substance possessing fairly good electrical resisting qualities together with chemical resisting qualities can be used. The transite tubes can also be replaced with glass tubes or tubes of other material that posesses good electrical and chemical resisiting qualities. On the inner face of each transite board are inserted a number of transita tubes varying in length from top to bottom, the shortest tubes being at thetop and the longest tubes at the bottom as illustrated in Figs. 1 and 5. Each tube carries a coil made into the^form of a conical spring with its base at the bottom of each tube.

vThe apex end of each of these wire cones tube and connects to the grid assembly,

which is placed in front of the board and tubes as shown in Fig. 1. The grid assembly is made up of taper bars that set in a vertical position in front of the board and tubes. There is an interval between each grid bar as shown in Fig. 3 and these bars are held in place by cross tie bars 40, 41 and 42, Fig. 3. To cross bar 41 is attached the electrical terminal 13. Each grid bar 17 tapers from its base to its top .on twol of its opposite sides as shown in Fig. 1. These tapered surfaces are saw toothed as is also shownl from and at right angles to the board hold; ing thegrid parallel to the board through- '-out as shown in Fig. 1. Each tube inserted in the board is at an angle to the board, pointing upward. The holes that are drilled in the board 14 to accommodate the tubes are drilled just far enoughto leave a thin wall at the bottom of each hole and then a hole somewhat smaller in diameter is drilled through from the opposite side of the board but at right angles thereto. This allows a wedge, shape shoulder for the bottom of each tube to rest against.

The operation ofthe cell is substantially as follows: After the cell has been assembled as shown in the accompanying drawings, an ionized solution, we will say or example, sodium hydrate, is introduced to the two parts of the cell 10 and 11 to a level lust covering the upper parts of the grids. he solution must be introduced to the two parts simultaneously to keep a static balance on both sides of the asbestos diaphragm 20, to prevent anyP possible` rupture in the diaphragm. 'Circulation of the electrolyte from one part lof the cell to the other can only take place through the tubes 15 and the asbestos diaphragm. After the electrolyte has been introduced and water placed in' vthe back.-

pressure regulator and indicator, a source of direct current electricity is connected to the terminals 13. -s the terminals themselves and all they internal conducting parts of the cell are insulated from the two sheet metal shells 23 ofthe casing, ythe current has vbut one path.k to follow and that is through the terminals, the grids, the coils, the asbestos curtain, and the space on each side of the curtain between the curtain and the bottom of each tube. The positive ions (assuming that the ionic theory is correct) collect on the coils and grids of the negative element combination and the negative ions collect on the coils and grids of the positive element combination. Hydrogen gas results on the negative side and oxygen gas on the positive in the proportion of H2O. The two gases are kept from mixing inside-the cell by the asbestos curtain which is firmly'- c-lamped between the two boards 14 of the element combinations. Gas is released from the coils in small bubbles but from the tubes in various sizes as a result of the accumulation of the smaller bubbles before release from the tubes. The surface tension of the larger bubbles thus formed do not appear to afect the polarization resistance of the coils even though they touch the coils in their release from the tubes. Owing to the arrangement of the tubes varying in length from the top to the bottom of the cell as l illustrated in Figures land 4, gas released from any particulartub has a clear path` upward, thus avoiding` a back pressure due to released bubbles striking other bubbles still in a state of formation on the elements. Only about one third of the gas,`however, is released from the tubes, approximately two thirds of the total amount being released from the-grid bars. The grid bars being tapered upward and having two opposite surfaces saw toothed as shown in Fig. 1, release the as in very small bubbles and give each -bub le of gas so released a chance to travel upward without interferin to any considerable extent with bubbles 'ab in the state of formation, thus making this' arrangement similar to that of the tubes. The coils in the tubes are constructed of the same size wire throu hout each element combination but these co1ls vary in the length of the wire used, the variation depending upon the length of tube in which any particular coil is placed.

The elect-rode element construction throughout including the gird bars, as can be seen in Fig. 1, provides a tapering cross sectional area from base to top and since the terminals are connected below the' center of the grids, the point of greatest intensity of the decomposing current is therefore throu h the bottom coils and the lower part of tie grid bars, this intensity diminishing at any point upward either in the coils or on lthe grid bars. This provision causes the internal -heat generated due to internal resistance tolikewise vary in intensity upward, diminishing as the intensity of: the current.

This. e'ect not only materially aids in the release of the gas bubbles from the element combinations but aids the rise of the bubbles through'the electrolyte after they have been released. The gasl accumulated above the upper surface of the electrolyte' being subjected to the same back pressure on each side of the cell due to the action of the back pressure regulators, brings very little stress to bear on the asbestos diaphragm in keeping the two'gases separated.

With' he arrangement as herein described, theasbestos diaphragm clamped as it is between two substantial boards and exposed to *stress only at vthe holes connecting the opposite tubes, is yin a position to withstan far'greater strain than with any arrangement heretofore used in electrolytic cells and should the diaphragm break down at ica lll@

any particular hole the 'leak may be simply remedied by plug that hole and dis ens- 'ng with the coil unit in that part o the electrode element.

, lclaim:

1. ln an electrolytic cell for the manufacture of gases, the combination with a casin consisting of two parts detachably secured together, of an electrode element in each of said parts, and a diaphragm permeable to the electrolyte mounted between the two parts of sai casing. i i

2. In an electrolytio-.cell jfor the manufaclao ture of gases, the combination with a casin consisting of two parts detachably secure together, of an electrode element in each of said parts including spaced grid bars and a plurality of coils of Wire connected to said grids, and a diaphragm permeable to the electrolyte mounted between the two parts of said casing.

3. In an electrolytic cell for the manufacl ture of gases, the combination of electrode elements each consisting of grid bars and a plurality of coils of wire connected to said bars, corresponding coils of opposing electrodes being placed in proximity, and a diaphragm permeable to the electrolyte inter-y posed between said coils.

4. In an electrolytic cell for the manufacture of gases, electrode elements, each consisting of grid bars and a plurality of coils of wire arranged so as to minimize resistance due to polarization. 5. In anelectrolyticcell for the manufacture of gases, electrode elements, each consisting ofgrid bars and a plurality of coils of wire so arranged that gas bubbles released therefrom have a clear path upward throu h the electrolyte.

6. n an electrolytic cell for the manufacaan ,'1

ture of gases, electrode elements, each consisting of grid bars and a plurality of coils of wires of different lengths connected thereto. 7. In an electrolytic cell for the manufacture of gases, an electrode element, consisting of tgrid bars and a lurality of coils of wire o diEerentlengt s, the latter being graduated from the top to the bottom of the cell in accordance with the length thereof. 8. In an electrolytic cell for the manufacture of gases, an electrode element consisting of grid bars of tapering cross sectional area, and a plurality of coils of wire connected thereto, and an electric terminal ,connected to said grid bars below the center thereof.

9. In an electrolytic cell for themanufac-

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