US3328235A - Electrical reactor and method for use thereof and products produced thereby - Google Patents

Description

AND PRODUCTS PRODUCED THEREBY 8 Sheets-Sheet 1 Filed Dec. 7, 1964 h Em mm h E J m 105 GOFU UI QOFM+QE31 a) Sn 2\ a Y mv Nm 6 wm w a nm S on m fiw mw fiw 33 E .W H 5% 4:. m E 1 2 m H P I on 6 g n? 3? v m$ .5 E hl' s l m R L EE m m fia- Z mm l v rm um m mom Q Fm F 5% @m 8 Inventor KURT E. SCHIMKUS J n 7, 1967 K. E. SCHIMKUS 3,328,235

ELECTRICAL AUT AN ETHOD FOR USE THEREOF DUCED THEREBY AN ROD '5 Filed Dec. '1", 1964 8 Sheets-Sheet 2 m FIG. 6 20 231 230 g5) 20:

20s 29; FIG. 5

2 220 2 3 $2: 3 {ll/l 32 //v 222 My 47 us 4A- xv an 202 zm 2m 253 52 56 c Inventor KURT E SCHIMKUS Jun 27. 1 6 K. E. SCHIMKUS 3,328,235

ELECTRICAL REACTOR AND METHOD FOR USE THEREOF AND PRODUCTS PRODUCED THEREBY Filed Dec- 7. 1964 8 Sheets-$heet a FIG. 7A 1 p. s.i.

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10 p. s.I.

30 p. s.I.

1/ 4244 1,, wi 4M 2 June 27, 1967 AND PRODUCTS PRODUCED THEREBY 8 Sheets-Sheet 4 Filed Dec. 3. 1964 m W ll 9 R w 8 6 m .l C F Y m G R H m n O m h m 61 o m w H T m o M W m m H U U 6 M\ R m m 06 m R P 3 L m v. m Q m M u. w I T R 8 E H m 2 m 4 w 1 M m w r W m w M W m u m a w w m 5 o a o m o 5 o wwmwiz Ewmmao 522E wwmwmzgmes 0 0 5: I so x 0 %355 0 0 June 27, 1967 E. SCHI us 3,323,235

ELECTRICAL REA R AND ME D USE THEREOF AND PRODUCTS PRODUCED REBY Filed Dec. 1'. 1964 8 Sheets-Sheet 5 Inventor By KURT E. SCHIMKUS June 27, 1967 K. E. SCHIMKUS 3,328,235

ELECTRICAL REACTOR AND METHOD FOR uss THEREOF AND PRODUCTS PRODUCED THEREBY Filed Dec. '9, 1964 8 Sheets-Sheet 6 ram FIG. l5

56\ 544 V 47 so 54 I o I 52 548 563 Invemor B KURT E. SCHIMKUS June 27. 1967 K. E. SCHIMKUS 3,328,235

ELECTRICAL REACTOR AN! METHOD FOR USE THEREOF AND PRODUCTS PRODUCED THEREBI' Filed Dec. 7, 1964 8 Sheets-Sheet 7 E gm 00 I I 3 CORN sTARcH I 300,000 WITHOUT sPARK it] -52 CHEEHAHGE. D I l U I 5200000 K CORN STARE FlG 6 o y WITH sPARK 2 T DISCHARGE. Z WAXY MAlZE STARCH g fl l64 wrrH SPARK DlSCHARGE. D.

O 2 4 6 8 l0 I2 I4 PASSES THROUGH THE REACTOR I00.

CORN sTARcH WITH sPARK DISCHARGE 5 6 b m g CORN sTARcH FIG. Q 2 7 WITHOUT SPARK z 2 DISCHARGE 6 g LIJ wm 8 I74 f f '1 m d 9 T WAXY MAIZE sTARcH 4 WITH SPARK DISCHARGE 2 0: CC LL] O 2 4 6 8 I2 I4 0.8 PASSES THROUGH THE REACTOR I00 CORN sTARcH |82 WITHOUT SPARK FIG '8 DISCHARGE.

3g CORN sTARcH 5 0.4 1 WITH sPARK 4 (I /DISCHARGE q 0 fnvenfor l4 PASSES THROUGH THE REACTOR By KURT SCHIMKUS United States Patent 3,328,235 ELECTRICAL REACTOR AND METHOD FOR USE THEREOF AND PRODUCTS PRODUCED THERE- BY Kurt E. Schimkns, Chicago, 111., assignor, by mesne assignments, to Ion Laboratories, Inc., Chicago, Ill., a corporation of Illinois Filed Dec. 7, 1964, Ser. No. 416,558 54 Claims. (Cl. 162-175) This application is a continuation-in-part of the copending application Ser. No. 52,136, filed Aug. 26, 1960, now abandoned, which latter application is a continuation-in-part of and was co-pending with application Ser. No. 761,870, filed Sept. 18, 1958, now abandoned.

The present invention relates to apparatus for and methods of treating materials by means of electrical discharge, and specifically by means of a spark, and to the products produced thereby.

It is an important object of the present invention to provide an improved apparatus for treating materials comprising a reaction chamber having a pair of spacedapart electrodes therein, there being provided structure for simultaneously passing a stream of liquid and a stream of gas through the gap between the electrodes, the gas continually purging the gap, and structure for causing a spark-type discharge between the electrodes and through the stream, the spark-type discharge liberating electrons and ions and free radicals and generating electromagnetic radiation and sound energy directly in the streams for treating material carried thereby.

Another object of the invention is to provide an improved apparatus of the type set forth wherein the position of the electrodes with respect to each other and within the reaction chamber is adjustable.

Yet another object of the invention is to provide an improved apparatus of the type set forth wherein one of the electrodes is annular and has at least the inner surface thereof disposed in the reaction chamber and the other electrode is spaced from the inner surface of the annular electrode to facilitate control of the paths of the liquid stream and the air stream between the electrodes.

Still another object of the invention is to provide an improved apparatus of the type set forth incorporating therein structure serving to confine the liquid stream to a layer on the inner surface of the outer annular electrode and directing the gas stream around the inner electrode in a manner to assist in maintaining the liquid stream on the inner surface of the outer annular chamber.

Yet another object of the invention is to provide in apparatus of the type set forth an improved structure of the reaction chamber which materially increases the time that the liquid stream is exposed to the action of the spark discharge between the electrodes.

Still another object of the invention is to provide in apparatus of the type set forth tWo inlet passages for liquid, one of the inlet passages serving to feed the liquid between the electrodes and the other inlet passage serving to feed liquid into the reaction chamber at a point such that the latter liquid is not subjected directly to the spark discharge between the electrodes.

Yet another object of the invention is to provide a modification of the electrode structure in apparatus of the type set forth, the electrodes in the modified structure being in axial alignment, and one of the electrodes being hollow to accommodate the How therethrough of liquid and gas.

Still another object of the invention is to provide in apparatus of the type set forth an improved power system for supplying energy to generate the spark discharge, the power source utilizing an applied A.C. frequency in the audio range at a potential of several thousand volts.

Patented June 27, 1967 ICC In connection with the foregoing object, another object of the invention is to provide an improved power source for apparatus of the type set forth wherein the capacitance forming a part of the power source and the gap between the electrodes is resonant in a radio frequency on the order of one megacycle.

Yet another object of the invention is to provide an improved method of treating materials utilizing the improved apparatus of the type set forth above.

Still another object of the invention is to provide an improved method of treating starch granules utilizing the apparatus of the type set forth above, the apparatus producing sparks liberating electrons and ions and free radicals and generating electromagnetic radiation and sound energy directly in a liquid stream carrying the starch, these phenomena breaking up the starch granules and causing chain scission of the starch and producing chemical groups on the starch that are effective to reduce ferricyanide solutions.

Yet another object of the invention is to provide an improved method of treating starch of the type set forth when the starch is presented to the apparatus in an aqueous slurry containing from about 0.5 to about 40% by weight starch at a pH in the range from about 1 to about 9 at a temperature in the range from ambient to about 140 F.

In connection with the foregoing object, another obiect of the invention is to provide an improved method of treating starch using apparatus of the type set forth wherein the starch is present in the spark discharge for time from about 0.01 second to about 0.3 second and the gas utilized to sweep the space between the electrodes has the velocity in the range from about 1 to about 5 ft. per second.

Yet another object of the invention is to provide an improved method of treating starch using apparatus of the type set forth above wherein the starch slurry has an acid pH, the preferred pH being in the range from about 1 to about 6, and the acid being of the type that will react with starch at a temperature in the range from about 70 F. to F. substantially only to hydrolyze the starch, the preferred acids being hydrochloric acid and acetic acid.

Still another object of the invention is to provide a method of treating starch using the apparatus of the type set forth, the gas stream flowing between the electrodes being air and the water stream carrying starch granules having a buffering agent therein, the preferred buffering agents when the pH is in the acid range being the amines and the ammonium ion, the preferred concentration range of the ammonium ion being from about 0.0003 to about 0.3 mole per liter; and the preferred buffering agents when in the pH is in the basic range being the oxides of boron, and preferably borate ions.

Yet another object of the invention is to provide an improved method of forming aqueous solutions of hydrogen peroxide utilizing the apparatus described above, the liquid stream preferably being acidified water and the gas stream being air.

Still another object of the invention is to provide an improved method of making paper utilizing a starch derivative made in accordance with the present invention, the starch derivative having an apparent molecular weight in the range from about 35,000 to about 350,000 and having a fcrricyanide reducing value in the range from about 14 to about 20.

In connection with the foregoing object, another object of the invention is to provide an improved method of making paper utilizing a starch derivative produced by the present invention wherein the starch contains at least 5% by weight amylose and the starch is preferably corn starch containing at least 20% by weight amylose, the starch derivative having a molecular weight in the range from about 150,000 to about 320,000 and a ferricyanide reducing value in the range from about 14 to about 17.

Yet another object of the invention is to provide an improved method of making paper wherein a starch derivative made in accordance with the present invention and the paper-making fibers are bent together to provide better association between the starch derivative and the paper fibers in the finished paper product.

Still another object of the invention is to provide an improved method of making paper wherein a starch slurry is first treated in accordance with the present invention, the reacted starch slurry is then diluted and cooked in a range temperature of 180 F. to about 200 F., after which the reacted starch slurry is added to the paper stock from which the paper is formed.

A further object of the invention is to provide a new derivative of starch characterized by an apparent molecular weight in the range from about 35,000 to about 350,000 and a ferricyanide reducing value in the range from about 14 to about 20.

In connection with the foregoing object, it is another object of the invention to provide an improved starch derivative containing at least about by Weight amylose, the preferred starch product being a derivative of corn starch containing at least about 20% amylose, and having an apparent molecular weight in the range from about 150,000 to about 320,000 and having a ferricyanide reducing value in the range from about 14 to about 17.

A still further object of the invention is to provide an improved paper product comprising paper-making fibers carrying a sizing of a starch derivative made in accordance with the present invention and characterized by an apparent molecular weight in the range from about 35,000 to about 350,000 and a ferricyanide reducing value in the range from about 14 to about 20.

In connection with the foregoing object, it is a further object of the invention to provide an improved paper product of the type set forth wherein the starch sizing includes at least about 5% by weight amylose, and preferably is a corn starch derivative including at least about 20% by weight amylose, and characterized by an apparent molecular in the range from about 150,000 to about 320.000 and a ferricyanide reducing value in the range from about 14 to 17.

Further features of the invention pertain to the particular arrangement of the apparatus and of the steps of the methods whereby the above-outlined and additional operating features thereof are attained. The invention, both as to its organization and method of operation, together with further objects and advantages thereof, will best be understoood by reference to the following specification taken in connection with the accompanying drawings, in which:

FIGURE 1 is a diagrammatic and schematic illustration of an apparatus made in accordance with the present invention and adapted to carry out the treating methods of the present invention;

FIG. 2 is an enlarged view in vertical section of the reactor forming a part of the apparatus illustrated in FIG. I of the drawings;

FIGS. 3, 4 and 5 are views in horizontal section through the reactor illustrated in FIG. 2 substantially as seen in the direction of the arrows along the lines 33, 4-4 and 5 5. respectively;

FIG. 6 is a fragmentary view in vertical section illustrating a modification of the reactor illustrated in FIG. 2;

FIGS. 7A through 7E constitute a series of diagrammatic views illustrating the time occurrence and intensity of infra-red radiation generated in the reactor of FIGS. 1 to 5 upon the application of different gas pressures to the reactor;

FIG. 8 is a graphical illustration of the relationship between the air pressure applied to the reactor and the energy supplied to the spark discharge and the ultraviolet light content of the spark discharge within the reactor;

FIG. 9 is a graphical representation of the relationship between the flow rate of a water stream through the reactor and the electrical energy supplied to the spark discharge, the hydrogen peroxide generated in the Water and the amount of ultraviolet radiation produced in the spark discharge, respectively;

FIG. 10 is a vertical front view in partial section of a third embodiment of a reactor made in accordance with the present invention;

FIG. 11 is a side elevational view of the reactor illustrated in FIG. 10;

FIG. 12 is a diagrammatic representation of an apparatus and system incorporating therein the form of the reactor illustrated in FIG. 10',

FIG. 13 is a side elevational View partly in section of a fourth embodiment of a reactor made in accordance with the present invention;

FIG. 14 is a front elevational view of a fifth embodiment of a reactor made in accordance with the present invention and illustrated as incorporated in an apparatus and system for carrying out the process of the present invention;

FIG. 15 is a view in vertical section through the reactor illustrated in FIG. 14;

FIG. 16 is a graphical illustration of the change in the apparent: molecular weight of various starch samples as a result of repeated passes through the reactor of FIGS. 1 to 5, the curves respectively illustrating the effect on corn starch with no spark discharge in the reactor, the eifect on corn starch with a spark discharge in the reactor and the effect on waxy maize starch with a spark discharge in the reactor;

FIG. 17 is a graphical illustration of the change in ferricyanide reducing value of various starch samples upon repeated passage thereof through the reactor of FIGS. 1 to 5, the starch samples being respectively corn starch with no spark discharge in the reactor, corn starch With spark discharge in the reactor, and waxy maize starch with spark discharge in the reactor;

FIG. 18 is a graphical representation of the change in apparent carboxyl group content of corn starch after repeated passes through the reactor of FIGS. 1 to 5, one of the curves representing the change with spark discharge in the reactor and the other curve representing the change without spark discharge in the reactor; and

FIG. 19 is a graphical illustration of the inter-relationship between the apparent molecular weight, the ferricyanide reducing value and the number of passes through the reactor of FIGS. 1 to 5, data being presented for corn starch treated with a spark discharge, corn starch treated without a spark discharge, waxy maize starch treated with a spark discharge, and corn starch not treated in the reactor but hydrolyzed in aqueous acid solution.

The apparatus 0 FIG. 1

There is illustrated in FIG. 1 of the drawings an apparatus 20 made in accordance with and embodying the principles of the present invention, the apparatus 20 including a reactor and the electrical, hydraulic and pneumatic components associated therewith. As illustrated in FIG. 1 the reactor 100 includes a reaction chamber 102 surrounding a gap or space between a pair of electrodes and 130, the electrode 120 being hollow and annular in configuration and the electrode being disposed substantially centrally therein. An inlet 107 for gas is provided in the upper portion of the reactor 100, an inlet 126 for liquid is provided through the electrode 120 and an outlet is provided in the bottom of the reactor 100 for venting the gas and liquid therefrom into a suitable receptacle such as the tank 141.

In the operation of the reactor 100, a high potential is applied between the electrodes 120 and 130 to cause the generation of sparks therebetween. The high operating potential is obtained from power supply which is connected to the standard 60 cycle 110 volt A.C. source such as the conductors 31 and 32, a pair of switches 33 and 34 and associated fuses 3S and 36 connecting the source to a pair of conductors 37 and 38, respectively, which are in turn connected by fuses 39 and 40 to the main conductors 41 and 42 within the power of supply for the apparatus 20.

The 110 volt potential applied between the conductors 41 and 42 must have the potential thereof increased before the application thereof to the reactor 100 and to this end a suitable transformer system has been provided including three variable transformers 70A, 70B and 70C connected in parallel and respectively providing an adjustable potential to the input of three high voltage transformers 80A, 80B and 80C also connected in parallel with each other. In order to connect the transformers to the conductors 41 and 42, a relay has been provided including a coil 51, an armature 52 and three sets of contacts, namely, contacts 53-54, contacts 56 and contacts 57-58. One terminal of the relay coil 51 is connected to the conductor 42 and the other terminal thereof is connected by a conductor 43 to one terminal of a normally open start switch 44 and to the contact 56. The other terminal of the start switch 44 is connected by a conductor 45 through a pump start switch 46 to the conductor 41, the pump start switch 46 being of the type which is normally open but remains closed after being moved to the closed position and remains there until the associated stop switch is moved to the open position; whereby an energizing circuit for the coil 51 is provided when both of the start switches 44 and 46 are closed, which circuit may be traced from the conductor 41 through the closed switch 46, the conductor 45, the closed switch 44, the conductor 43, and the relay coil 51 to the other main conductor 42. As soon as the relay coil 51 is energized, all three sets of contacts are closed; more specifically, the contact pair 53 54 is closed to connect the conductor 41 to a conductor the contact pair 55-56 is closed to establish a holding circuit for the relay coil Si; and the contact pair 5758 is closed to connect the conductor 42 to a conductor 61. The contact 55 is connected by a conductor 47 to a normally closed stop switch 48 that is in turn connected by a conductor 48o through a normally closed stop switch 49 to the conductor 41. After the relay coil 51 has been energized, a holding circuit therefor is provided as follows: from the conductor 41 through the normally closed stop switch 49, the conductor 48a, the normally closed stop switch 48, the conductor 47, the now closed contact pair 5556, and the relay coil 51 to the conductor 42; this holding circuit maintains the relay coil 51 energized to hold the contacts thereof closed even after the normally open start switch 44 has moved from the manually depressed closed position thereof to the normally open position thereof. A pilot light 51a is provided to indicate when the pump start switch 46 is closed, the light 510 being connected between the conductors 42 and 45, and the conductors 42 and 45 also are connected as the input to a pump motor 95 which will be described further hereinafter.

After the energization of the relay coil 51 so as to close the contact pairs 5354 and 57-58, direct electrical connection is provided between the conductors 41 and 42 and the respective conductors 60 and 61. A pilot light 59 is connected between the conductors 60 and 61 to provide a visual indication that the relay 50 has been operated and that operating potential is present on the conductors 60 and 61. The potential between the conductors 60 and 61 is also applied to the variable transformers 70A, 70B and 70C; more specifically, the conductor 60 is connected to one terminal of the ammeters 62A, 62B and 62C, the other terminals of the ammeters being connected by conductors 63A, 63B and 63C, respectively, to connections 71A, 71B and 71C on the variable transformers 70A, 70B and 70C, respectively. The other terminals of the variable transformers are all connected to the conductor 61. Each of the variable transformers is provided with a movable contact 73A, 73B and 73C, respectively, thereon so that any desired potential of approximately 0 volts to approximately 130 volts may be obtained between the movable eontact and the conductor 61. A voltmeter is provided for each of the variable transformers between the movable contact thereof and the conductor 61, the voltmeters being designated by the numerals 64A, 64B and 64C, respectively. Preferably the movable contacts 73A, 73B and 73C are mechanically interconnected so that they can be operated together by a single control diagrammatically represented at 74.

The potentials appearing between the movable contacts of the variable transformers and the conductor 61 are applied as the inputs to the high voltage power transformers A, 80B and 80C, respectively. More specifically, each of the power transformers has a primary winding that is connected between the associated movable contact and the conductor 61, the primary winding 81A having one terminal thereof connected to the conductor 61 and the other terminal thereof connected by the conductor 65A to the movable contact 73A; the primary winding 818 having one terminal thereof connected to the conductor 61 and the other terminal thereof connected by the conductor 653 to the movable contact 73B; and the primary winding 81C having one terminal thereof connected to the conductor 61 and the other terminal thereof connected by the conductor 65C to the movable contact 73C. Each of the power transformers is likewise provided with a secondary winding 82A, 82B and 82C, respectively, one terminal of each of the secondary windings being connected to a con ductor 83 and the other terminal of each of the secondary windings being connected to a conductor 84. In a specific example of the power supply 30, the power transformers 80A, 80B and 80C produce approximately 12,000 volts in the secondary windings thereof upon the application of 110 volts to the primary windings thereof upon the application of 110 volts to the primary windings thereof and the combined current output of the transformers is on the order of 300 milliampcres for continuous operation.

The high potential between the conductors 83 and 84, for example the potential of approximately 12,000 volts, is applied to a bank of capacitors 85 connected in parallel relationship with each other, preferably of the capacitors 85 being provided in a typical illustrative example of the apparatus 20. Each of the capacitors 85 has a value of 500 micr-omicrofarads and is capable of withstanding 35,000 volts D. C. peak voltage thereacross, whereby the capacitor bank has a total capacitance of 0.05 microfarad. The conductors 83 and 84 are further connected to a pair of electrodes 86 and 87 which are spacedapart in an air atmosphere and are designed to provide a spark or are therebetween at a potential well below the breakdown potential of the capacitors 85, for example, at a potential of 20,000 volts so that the electrodes 86 and 87 serve as a safety gap for the power system 30. Finally, the conductor 83 is connected to the outer annular electrode and the conductor 84 is connected to the inner electrode to provide the operating potential for the reactor 100.

In the operation of the reactor 100 it is necessary to provide a stream of gas to sweep the gap between the electrodes 120 and 130 therein, and as is illustrated in FIG. 1, a suitable gas for this purpose in many reactors is air. There is shown the usual air line 88 to which is connected in series an air filter 89, a pressure regulator 90, a meter 01, the air line 88 communicating with the reactor chamber 102 within the reactor 100 through the inlet port 107. The pressure regulator 90 is useful to adjust and to regulate the pressure in the inlet port 107 at a value from essentially 0 p.s.i. to about 100 psi.

It will be understood that the material to be treated in the reactor 100 may be carried by the air stream entering through the port 107, but usually the material to be treated is carried by a liquid stream that enters through a port 126 in the electrode 120. A suitable source of liquid is provided such as the tank 92 into which extends a takeup pipe 93, the pipe 93 extending substantially to the bottom of the tank 92. The upper end of the pipe 93 connects to the input of a pump 94, the pump 94 being driven by a pump motor 95 through a drive coupling 96; the pump motor 95 has the electrical input terminals thereof connected respectively to the conductors 42 and 45, whereby the motor 95 is operated upon closure of the switch 46 to cause operation of the pump 94. The outlet port of the pump 94 is connected through a flow control valve 97 and a flow gauge 98 to a pipe 99 that communicates with the inlet port 126 for the reactor 100. It will be understood that operation of the pump 94 serves to move the liquid within the tank 92 therefrom and through the pipe 93, the how control valve 97, the flow gauge 98 and the pipe 99 into the reactor 100.

The reactor of FIGS.

The details of construction of the reactor 100 are best illustrated in FIGS. 25 of the drawings. Referring to FIG. 2, the reactor 100 includes an upper housing 101, a lower housing 111, an outer annular electrode 120 and an inner electrode 130. The upper housing 101 and the lower housing 111 are preferably formed of an insulating material, such as a synthetic organic plastic resin, the preferred material of construction being methyl methacrylate resin. The general shape of the reactor 100 is cylindrical and the upper housing 101 more specifically is formed externally as a cylinder provided with an opening generally centrally thereof contributing to form the reactor chamber 102, an upper inner wall 103 being providecl arranged essentially horizontally and connecting with a generally conically shaped inner wall 1.04 diverg ing downwardly therefrom. The upper end of the housing 101 has an opening 105 therein receiving therethrough a portion of the inner electrode 130 and the lower end of the housing 101 has a threaded recess 106 therein for connection to the annular electrode 120. There also is provided in the housing 101 adjacent to the upper end thereof the inlet port 107 which communicates with a coupling 108 mounted on the housing 101 and providing a fluid-tight connection therewith and also with the air inlet pipe 88.

The lower housing 111 is also cylindrical in shape and is provided with an opening centrally thereof to form a part of the reactor chamber 102, an inner wall 113 being provided that is generally conical in shape and converges downwardly from a larger diameter as at 114 to a relatively small outlet opening 115 in the bottom of the housing 111. The upper end of the housing 111 is provided with a threaded recess 116 therein that threadedly engages the outer electrode 120 to assemble the housing 111 thereto.

As will be explained in greater detail hereinafter, both the gas stream and the air stream introduced into the reactor 100 are directed in circular or spiral paths so that these streams are in essentially a spiral condition as they enter the lower housing 111. In order to minimize interference with the exit of these streams from the lower end of the housing 111, a bafile 117 has been provided in the lower housing 111. As may be best seen in FIG. 5 of the drawings, the baffle 117 extends across a diameter of the opening in the end of the housing 111 and is connected thereto adjacent to the upper end of the battle 117 and adjacent to the lower end thereof. The outer edges of the bnfilc 117 are spaced from the inner wall of the housing 111 throughout the greater portion of the length thereof as at 118 to provide restricted channels between the edges of the baffle 117 and the inner wall of the housing 111.

There also is provided a cross-support 119 connected to the lower end of the baffle 117 and disposed in the opening to assist in centering the battle 117 within the housing 111. Preferably the bafile 117 and the cross-support 119 are also formed of a synthetic organic plastic resin such as methyl methacrylate resin. The upper end of the pipe 140 is disposed in a recess communicating with the open ing 115 in the bottom of the housing 111 and is secured thereto and extends downwardly therefrom and into the tank 141 (see FIG. 1).

The outer annular electrode 120 and the inner electrode 130 are both preferably formed of materials that are good conductors of electricity, a preferred material of construction for both electrodes being aluminum metal. It will be understood that other suitable conducting materials and particularly conducting metals may be used when the materials being treated indicate that this would be desirable.

The electrode 120 is essentially annular in shape having a generally cylindrical outer surface of the same general diameter and shape as the housings 101 and 111 and a generally cylindrical inner surface forming a part of the wall of the reactor chamber 102. An upwardly extending threaded flange is provided on the upper end of the electrode 120 that threadedly connects with the threads on the recess 106 of the upper housing 101; a downwardly extending threaded flange 122 is provided on the lower end of the electrode 120 that threadedly connects with the threads on the recess 116 of the lower housing 111; whereby the upper housing 101, the annular electrode 120 and the lower housing 111 can be threadedly interconnected to provide the reactor 100 containing and defining the reactor chamber 102 therein. The inner surface of the annular electrode 120 is provided with a helical groove 123 therein which spirals downwardly from the upper end thereof to the lower end thereof and tends to direct a liquid stream or the gas stream impinging thereon in a downwardly spiraling path. Formed in the electrode 120 is a passage 124 communicating at one end with the exterior thereof and specifically with a coupling 125 that connects to the pipe 99 and at the other end communicates with an inlet port 126 on the inner surface of the annular electrode 120, see FIG. 4. There further is provided in the electrode 120 a threaded opening on the exterior thereof that receives a screw 127 that connects the adjacent end of the conductor 83 to the electrode 120 to apply operating potential thereto.

The inner electrode 130 includes an upwardly extending stem or rod 131 that is generally circular in cross section and extends upwardly through the opening 105 in the upper end of the upper housing 101 and in operation is connected to the conductor 84 for the application of operating potential thereto. The lower end of the rod 131 carries an enlarged head 132 which is formed with an upwardly and inwardly sloping conical surface 133. a downwardly and inwardly sloping conical surface 134 and a cylindrical surface 135 joining the surfaces 133 and 134. Substantially all portions of the surface 135 are equidistantly spaced from the adjacent inner surface of the annular electrode 120 to provide therebetween a gap across which a spark discharge is produced upon the application of operating potential between the electrodes 120 and 130, as will be explained more fully hereinafter.

Referring now specifically to FIGS. 3 and 4 of the drawings, the manner in which a downwardly spiraling action is applied to both the gas stream and the liquid stream within the reactor 100 will be described in detail. Referring first to the gas stream, it will be seen from FIG. 3 of the drawings that the inlet port 107 is directed tangentially with respect to the inner annular wall 104 of the upper housing 10], whereb gas entering through the port 107 is impinged upon the annular wall 104 and is forced into a circular or spiraling path. The direction of spiraling of the gas stream imparted thereto by the configuration of FIG. 3 is in a like direction and like sense as the groove 123 on the inner surface of the annular electrode 120. The liquid stream inlet 124 and the port 126 therefore are also disposed tangentially with respect to the inner surface of the annular electrode 120, see FIG. 4, whereby to impart to a liquid stream entering therethrough a spiraling motion, the direction and sense of the spiraling motion imparted to the liquid stream being the same as the direction and sense of the groove 123 on the inner surface of the annular electrode 120. The like downward spiraling motion of the gas stream also reinforces the motion of the liquid stream and together with centrifugal force serves to hold the liquid stream in a spiraling, annular and gradually falling path along the groove 123 of the annular electrode 120 so that the liquid stream travels a path having a substantial length in moving from the inlet port 126 to the lower end of the annular electrode 120, it being pointed out that the liquid stream is in the gap between the electrodes 120 and 130 so long as it is in position in the groove on the electrode 120.

In an illustrative example of the reactor 100, the overall length of the reactor is 6.5" and the diameter thereof is 2.4"; the diameter of the reaction chamber 102 at the upper end thereof is 1.1" and the maximum internal diameter thereof is 1.65; the longitudinal extent of the helical groove 123 is 0.625, the pitch of the groove 123 is 6 /2 turns per inch, and the internal diameter of the electrode 120 is approximately 1.655"; the diameter of the air inlet port 107 is 0.085" and the diameter of the liquid inlet port 126 is 0.098"; the maximum diameter of the inner electrode head 132 is 0.825, whereby the minimum spark gap between the electrodes 120 and 130 is 0.415"; the head 132 is further positioned approximately midway between the inlet port 126 and the lower edge of the annular electrode 120 so as to provide a maximum exposure of the liquid stream to the spark.

The reactor of FIG. 6

There is illustrated in FIG. 6 of the drawings a modification of the reactor 100 described above with respect to FIGS. 2-5 of the drawings; where appropriate, like numerals in the 200 series have been applied to parts of the reactor 200 to correspond to like parts of the reactor 100 described above.

The reactor 200 includes an upper housing 201, a lower housing 211, an outer annular electrode 220 and an inner electrode 230. The upper housing 201 is formed identical with the housing 101 described above and as illustrated includes an inner annular wall 204 defining a portion of the reactor chamber 202 and a threaded recess 206 at the lower end thereof for connecting the electrode 220. The lower housing 211 is of modified construction and is formed with an internal cylindrical wall 213 that is formed as a continuation of the inner wall of the annular elcctrode 220. The lower end of the housing 211 is provided with a threaded recess 215 for connection to an outlet battle to be described hereinafter. There further is provided in the upper portion of the housing 211 a second liquid stream inlet 244 communicating at one end with a coupling 245 mounted on the housing 211 and connecting to a second liquid inlet pipe 247; the other end of the inlet passage 244 communicates with a second inlet port 246 in the wall of the housing 211 and disposed below the annular electrode 220 for the introduction for a second or additional stream of liquid or gas if desired.

The lower end of the housing 211 is closed by a baflle 250, the baffle 250 having an outer annular wall threaded as at 251 and threadedly engaging the threaded recess 215 to mount the bafile 250 on the lower end of the housing 211. The upper portion of the battle 250 extends into the housing 211 and terminates in an upwardly disposed conical surface 252 that merges with a vertical annular wall 253 spaced from the inner annular wall 213 of the housing 211. The lower end of the baffle 250 carries a downwardly directed annular projection 254 which is provided inwardly thereof with an upwardly extending vertical passage 255 extending upwardly toward but spaced from the conical surface 252. A plurality of horizontally disposed and axially arranged passages 256 are provided communicating between the outer annular wall 253 and the vertical passage 255, four of the horizontal passages 256 being provided, for example.

The annular electrode 220 is formed substantially identical with the annular electrode 120 described above and more specifically includes an upwardly directed threaded flange 221 threadedly engaging the lower end of the upper housing 201 as at 206, and a downwardly extending threaded flange 222 threadedly engaging the threaded recess 216 on the upper end of the lower housing 211. The inner surface 223 of the electrode 220 is formed smooth and as a cylinder having a diameter substantially equal to the diameter of the surface 213 on the lower housing 211. A first liquid stream inlet passage 224 is provided communicating at the other end with the coupling 225 connected to the pipe 99 and communicating at that end with an inlet port 226 disposed above the head 232 on the inner electrode 230.

The inner electrode 230 is formed identical to the inner electrode 130 described above, and more specifically, includes an upward extending rod 231 carrying at the lower end thereof a head 232 having an upper conical surface 233, a. lower conical surface 234 and an annular surface 235 joining and interconnecting the conical surfaces 233 and 234. The annular surface 235 of the inner electrode 230 is spaced from the inner surface 223 of the outer electrode 220 completely therearound to provide a uniform spark gap therebetween.

The reactor 200 can be readily inserted in the apparatus 20 of FIG. 1 for the reactor illustrated therein. The annular electrode 220 is connected to the conductor 83, the inner electrode 230 is connected to the conductor 84, the first inlet coupling 225 is connected to the pipe 99 and the second inlet coupling 245 is connected to the pipe 247 which is in turn connected to a liquid supply system like that supplying the pipe 99. The materials of construction and the relative sizes of all parts of the reactor 200 are the same as for the like parts of the reactor 100 described above.

Operation of the apparatus 20 In the operation of the apparatus 20, the parts are first connected as illustrated in FIG. 1 of the drawings. A suitable supply of desired liquid is placed in the tank 92 and a source of air under pressure is connected to the pipe 83. The power supply 30 is then energized by closing the switch contacts 33 and 34 so as to supply line potential of approximately volts ac. through the fuses 3S and 36, the conductors 37 and 38, and the fuses 39 and 40 to the main conductors 41 and 42. The pump start switch 46 is then closed to provide a connection from the conductor 41 through the switch 46 to the conductor 45 connected to one terminal of the pump drive motor 95, and from the other terminal of the pump drive motor 95 to the main conductor 42; simultaneously, energization potential is applied to the signal light 51A to indicate that the pump 95 is operating. The pump motor 95 acting through the coupling 96 drives the pump 94 to draw liquid from the tank 92 through the pipe 93 into the inlet port of the pump 94 and out of the outlet port of the pump 94 and through the valve 97, the meter 98 and the pipe 99 to the inlet port 126 of the reactor 100. The operation of the pump 94 and the setting of the valve 97 are adjusted to produce the desired fiow rate of liquid into the reactor 100 a typical operating flow rate of the liquid at the port 126 as indicated by the flow meter 98 is in the range from about 0.05 gallon per minute to about 1.5 gallons per minute, a typical operating value being 0.6 gallon per minute. The force of the liquid striking the inner surface of the electrode and particularly the helical groove 123 therein forces the liquid into a swirling motion and substantially confines it to a thin film upon the electrode 120, the residence time of the liquid in the spark gap between the electrodes 120 and 130 being for examples 0.8 second at a flow rate of 0.05 gallon per minute and 0.027 second at a flow rate of 1.5 gallons per minute, a typical operating value being 0.069 second at a flow rate of 0.6 gallon per minute. The tangential entry of the port 126 with respect to the helical groove 123 materially assists in imparting a swirling motion to the liquid stream as it falls downwardly through the spark gap between the electrodes 120 and 130 along the helical groove 123.

The gas supplied through the pipe 88 and into the reactor 100 also assists in holding the liquid stream in the desired configuration upon the inner surface of the anular electrode 120. The air pressure as measured by the gauge 91 and as controlled by the pressure regulator 90 may be in the range from about psi. to about 80 psi. or higher, a typical operating value being p.s.i. when the gas being used is air; the air flow at 5 p.s.i. is approximately 1.8 cu. ft. per minute which results in each quantity of air passing through the spark gap between the electrodes 120 and 130 in a time period of approximately 0.047 second; at the operating pressure of 10 p.s.i., the air flow rate is approximately 1.5 cu. ft. per minute and the time required for the air to pass through the spark gap is approximately 0.036 second; and at an air pressure of p.s.i., the flow rate of air is about 3.75 cu. ft. per minute and requires about 0.023 second for the air to pass through the spark gap. The gas velocity through the reactor 100 is in the range from about 1 foot per second to about 5 feet per second. The air flowing around the inner eiectrode 130 and against the inwardly disposed surface of the liquid stream serves to assist in holding the liquid stream in the desired position and against the inner surfaces of the annular electrode 120 and particularly in the helical groove 123 thereof. The gas entering the reactor 100 through the port 107 also serves to sweep particles from the spark gap between the electrodes 120 and 130 as will be described more fully hereinafter.

With the gas stream flowing through the reactor 100 and specifically through the spark gap between the electrodes 120 and 130, the reactor start switch 44 may now be closed. Closure of the reactor start switch 44 completes a circuit from the conductor 41 through the pump start switch 46, the conductor 45, the reactor start switch 44, and the conductor 43 to one terminal of the relay coil 51; and from the other terminal of the relay coil 50 to the main conductor 42, whereby to energize the coil 51 and to move the armature 52 thereof to close the associated pairs of relay contacts 53-54, 55-56 and 57-58. Closure of the relay contacts 55-56 creates a holding circuit for the relay coil 51, it being pointed out that although the pump start switch 46 is of the type that remains closed after having been moved to that position, the reactor start switch 44 is of the momentary contact type and will be immediately moved to the open position upon release of the closure pressure therefrom. The holding circuit for the relay coil 51 can be traced from the main conductor 41 through the normally closed pump stop switch 49, the conductor 480, the normally closed reactor stop switch 48, the conductor 47, the now closed relay contacts 55-56, the conductor 43, the relay coil 51 and to the other main conductor 42. In passing it is noted that the start reactor switch 44 is ineffective to actuate the relay 50 if the pump start swich 46 is not closed, whereby to insure that a liquid stream is present in the reactor 100 before closure of the relay contacts 53-54 and 57-58 for a purpose which will be explained hereinafter.

Energization of the relay coil 51 causes closure of the relay contacts 53-54 that provide a connection between the main conductor 41 and the conductor 60; and actuation of the relay 50 likewise closes relay contacts 57-58 that serve to connect the main conductor 42 to the conductor 61. Connection of the conductors 41 and 42 to the conductors 60 and 61, respectively, applies 110 volt A.C. operating potential between the conductors 60 and 61; the signal light 59 is immediately energized to indicate that the relay is in the operating osition thereof.

Application of the operating potential to the conductors 60 and 61 immediately applies that potential to the variable transformers A, 70B and 70C. The operating potential is applied to the variable transformer 70A, for example, from the conductor 60 through the ammctor 62A and the conductor 63A to one of the input terminals thereof and from the conductor 61 directly to the other input terminal thereof. The potential derived from the variable transformers 70A, 70B and 70C and applied as the input to the step-up transformers A, 80B and 80C, respectively, depends upon the setting of the contacts 73A, 73B and 73C, the input potential to the step-up transformers being that between the conductor 6-1 and the conductors 65A, 65B and 65C, that potential being adjustable by means of the linkage 74 interconnecting the sliding contacts 73A, 73B and 73C, respectively; the value of the operating potential applied as an input to the stepup transformers is indicated by the meters 64A, 64B and 64C connected across the primary windings 81A, 81B and 81C, respectively. In a typical operating example, the stepup transformers are of a type and the adjustment of the control 74 is such that 12,000 volts A.C. are developed as outputs from the secondary windings 82A, 82B and 82C of the step-up transformers, which potential is applied through the conductors 83 and 84 to the bank of capacitors 85 and serves to charge the capacitors 85 toward the peak voltage, which is, for example, approximately 17,000 volts when the output from the secondary windings of the step-up transformers is 12,000 volts R.M.S. The potential on the capacitors 85 is applied by the conductors 83 and 84 to the electrodes 120 and 130, respectively, of the reactor 100.

The operation of the power supply 30 can be interrupted by opening either the normally closed reactor stop switch 48 or the normally closed pump stop switch 49, these switches being in series in the holding circuit for the relay coil 51. Opening either of these switches deenergizes the coil 51 and causes the movable relay contacts 53, 55 and 57 to move to the open positions thereof, thus removing operating potentials from the variable transformers 70A, 70B and 70C, and consequently interrupting the power for the spark discharge in the reactor 100. If only the reactor stop switch 48 is opened, the pump motor will continue to operate; on the other hand, if the pump stop switch 49 is opened, then the pump start switch 46 is likewise opened and operation of the pump motor 95 is stopped.

The discharge between the electrodes and during the operation of an apparatus 20 is believed to be fundamentally a spark discharge, as distinguished from a glow or an arc discharge. In fact the spark discharge can be considered to be a transitional breakdown which occurs in transition from a glow discharge to an arc discharge. The conditions under which a spark discharge is obtained, and specifically the breakdown or sparking potential depends upon many factors including the pressure within the reaction chamber 102 and the separation or distance between the electrodes 120 and 130 and specifically is a function of the product of the pressure and the electrode seperation. In order to encourage the formation of the more desirable spark discharge, it is preferred to operate the reaction chamber 102 at approximately atmospheric pressure, and even at an air pressure of 20 psi. as indicated by the gauge 91, the actual pressure as determined by a pressure probe in the spark gap being on the order of 3" of water above atmospheric. Either an increased pressure or a decreased pressure tends to discourage and prevent a sparktype discharge between the electrodes 120 and 130.

In a spark discharge, the entire path between the electrodes 120 and 130 is ionized and a characteristic light is emitted from the path of the spark discharge. The light is in turn caused by the photon emission resulting from the recombination and the decay from excited states to more stable states of orbital electrons in atoms along the spark path. The spark is propagated at a rapid rate across the gap and is propagated at a rate much faster than electrons can traverse the spark gap. It is believed that initially an electron is emitted from the electrode that is acting as a cathode, and this initial electron will produce a heavy avalanche of cumulative ionization along the spark path. The light resulting from the decay processes referred to above will also produce ionization throughout the gas present between the electrodes, and the light will also produce electrons at electrode surfaces by the photoelectric effect. The resultant electrons from these phenomena will in turn produce further avalanches through the entire spark gap, so that in a time on the order of second the entire path between the electrodes 120 and 130 becomes conducting. At the approximately atmospheric pressure prevailing through out the spark gap within the reactor 100, the spark will be confined to a relatively narrow region, so that the conducting path while not straight will be a well-defined line.

It will be seen that there will be formed in the spark gap a substantial quantity of electrons and ions, which electrons and ions will be present in both the gas stream and the liquid stream and therefore will be in intimate contact and association with any reactants carried thereby, whereby to provide maximum opportunity for chemical and physical reactions occurring therefrom. If certain types of molecules are present, such for example as water, free radicals are also readily formed and are available for reaction with reactants present in the spark gap, the free radical being intimately mixed throughout the spark gap and therefore intimately mixed with the reactants therein.

The photons produced in the spark also provide a substantial source of electromagnetic radiation which varies in wavelength from the infra-red region through the visible region to the ultra-violet region of the spectrum. Substantial quantities of electromagnetic radiation are produced as determined by measurement with meters as will be described more fully hereinafter. The electromagnetic radiation is present directly in the spark gap and therefore is brought into intimate contact with any reactants present within the spark gap, whereby maximum utilization can be made thereof in carrying out the reactions Within the reactor 100.

The rapid heating and cooling of quantities of gas within the reactor 100 also produces a substantial amount of sound energy that is present directly in the gas and liquid streams and also imparts energy to the reactants present therein. In this connection it also is pointed out that the swirling motion of both the gas stream and the liquid stream results in a high shear action upon materials carried thereby within the reactor 100. As a result of these phenomena, operation of the reactor 100 is characterized by a high shrill piercing sound that demonstrates the high amount of energy available from these sources within the reactor 100.

It is also found that a more desirable form of discharge is obtained when the operating potential is in the range from about 4,500 volts to about 20,000 volts or higher between the electrodes 120 and 130. The preferred operating potential when using the reactor 100 having the dimensions described above is 9,000 volts, which value is readily attained by producing a 12,000 volt output from the secondary windings of the step-up transformers 80A. 80B and 80C. A more desirable form of spark discharge is also obtained if the capacitance represented by the capacitance represented by the capacitors 85 and the reactance of the remainder of the power source 30 and the spark gap between the electrodes 120 and 130 is resonant at a radio frequency, the preferred value being approximately 1 megacycle. It will be understood that the system has a low Q, whereby there is substantial radiation at frequencies above and below 1 mcgacycle, but there is a definite maximum radiation at approximately 1 megacycle as determined by measurement using an absorption meter. It can be demonstrated mathematically that with the above conditions, very high concentrations of power are produced in the spark, these concentrations of power being on the order of 1 to 10 megawatts, whereby substantial amounts of power and energy are available at points within the reaction chamber 102 to elToct reactions between the materials carried by the gas stream and the liquid stream therein.

A most important factor in obtaining a desirable spark discharge within the reactor is the pressure of the gas stream entering through the inlet port 107. The gas stream serves to sweep the area between the electrodes I20 and and is believed therefor to discourage arc discharge and to encourage spark discharge by quickly extinguishing any incipient arc discharges that may occur in the spark gap. Referring to FIGS. 7A to 7E of the drawings, there are illustrated replicas of actual experimental data which indicate that both the frequency of spark discharge and the intensity of spark discharge is increased with an increase in the inlet gas pressure at the inlet port 107. The data in FIGS. 7A to 7E were obtained by using distilled water as a liquid stream at a flow rate of 0.5 gallon per minute through the reactor 100, and utilizing air as the gas stream at various pressures as indicated by the pressure gauge 91 in FIG. 1. The frequency and intensity of spark discharge was determined by measuring the infra-red energy generated by the spark discharge, an infra-red sensitive photometer being utilized in combination with an infra-red filter to detect the infrared energy and to convert that energy into a corresponding electrical signal that was displayed upon the face of an oscilloscope. In FIGS. 7A to 7E there are shown reproductions of actual oscilloscope tracings having a horizontal extent equal to three cycles of the applied potential on the conductors 83 and 84, the frequency of the spark discharge being determined by the occurrence of the vertical peaks and the intensity of the spark discharge being indicated by the length of the vertical peaks.

There is shown in the graph of FIG. 7A the frequency and intensity of spark discharge obtained when the air inlet pressure as indicated by the gauge 91 was 1 p.s.i. It will be noted that there were approximately four spark discharges per cycle of the applied operating potential and with an intensity on the order of 1 to 2 of the arbitrary units illustrated. The graph in FIG. 7B represents the spark discharge obtained when the air pressure is indicated by the gauge 91 is increased to 10 p.s.i. It will be noted that there is a general increase in both the frequency and in the intensity of the spark discharge. The graph in FIG. 7C represents the discharge when the air pressure as indicated by the gauge 91 is 30 p.s.i. and indicates yet further increase in the frequency and the intensity of the spark discharge. In the graph of FIG. 7D there is illustrated the spark discharge obtained when the air pressure is indicated by the gauge 91 is 50 p.s.i. and a yet further increase in the frequency and intensity of the discharge is noted. Finally in the graph of FIG. 7E there is illustrated the spark discharge obtained when the air pressure as indicated by the gauge 91 was 80 p.s.i. and showing yet a further increase in both the frequency and intensity of spark discharge in the spark gap between the electrodes 120 and 130.

As has been pointed out above, ultra-violet radiation is also produced by the spark discharge. By means of an ultra-violet meter the change in ultra-violet radiation production by the spark discharge was measured at various air pressures as indicated by the gauge 91. The results are plotted in FIG. 8 on the curve the vertical axis indicating the DC. microamperes measured by the ultraviolet meter and the horizontal axis indicating the air pressure in psi. as measured by the gauge 91. It will be noted that the ultra-violet increased from a value of 10 microamperes at an inlet air pressure of psi. to a value of 18 microamperes at an air pressure of 60 p.s.i., in dicating that more spark discharge was obtained as the inlet air pressure is increased, thus confirming the data presented in FIGS. 7A to 713 described above. There also is plotted in FIG. 8 a curve 185 of the total primary current in amperes as indicated by the meters 62A, 62B and 62C versus the inlet air pressure. It will be noted that the primary current increased from a value of 27 amperes at an inlet air pressure of 5 psi. to a value of 34 amperes at an inlet air pressure of 60 p.s.i. indicating that more energy was being transferred from the power source 30 to the reactor 100 as the inlet air pressure increased, and therefore also confirming the data presented in FIGS. 7A to 7E as well as confirming the data presented in the curve 180.

The fiow rate of the liquid stream also affects the type of spark discharge obtained, the frequency and intensity of the spark discharge generally decreasing with an increased liquid stream flow. There is plotted in FIG. 9 of the drawings curves representing the effect of different water flow rates as indicated by the flow meter 98 in FIG. 1 (plotted along the horizontal axis) upon the ultra-violet radiation produced in the water stream expressed in grants per liter and the amount of current indicated by the meters 62A, 62B and 62C expressed in amperes (the latter variables being plotted on the vertical axis).

Referring to FIG. 9, the curve 190 is a plot of the amount of ultra-violet radiation produced from the spark gap as indicated by the ultra-violet meter and expressed in DC microamperes with varying flow rates of water as measured by the flow meter 98 in cc. per minute. It will be noted that the ultra-violet generated varies from a value of 20 microamperes at a flow rate of 270 cc. per minute to a value of 10 microamperes at a flow rate of 1,700 cc. per minute, i.e., the ultra-violet radiation produced in the spark gap within the reactor 100 generally decreases as the rate of flow of water through the reactor increases.

As has been mentioned above, the passage of the spark through air and distilled water in the reactor 100 is believed to produce free radicals, and in any event, hydrogen peroxide is produced therein. As is indicated by the curve 193 in FIG. 9, at a water flow rate of 270 cc. per minute, 0.027 grams of hydrogen peroxide are generated per liter of water flow through the reactor 100. The amount of hydrogen peroxide produced decreases to a value of approximately 0.016 grams per liter at a flow rate of 1800 cc. per minute; whereby it will be seen that the amount of hydrogen peroxide produced decreases with an increase in the flow rate of the water through the reactor 100 and decreases in a manner generally corresponding to the decrease in the ultra-violet radiation.

The decrease in energy consumed in the reactor 100 with the increased flow rate of water thereto is confirmed by measuring the current in the power supply 30 as indicated by the meters 62A, 62B and 62C. The graph 196 in FIG. 9 is a plot of the current indicated by those meters versus the flow rate, whereby it will be seen that a flow rate of 270 cc. per minute, the total current drawn is 37 amperes, and as the water flow rate increases the current drawn decreases so that at a flow rate of 1700 cc. per minute the current drawn is only 23 amperes. This confirms the data indicated by the curves 190 and 193 dis cussed above, namely, that there is less energy transferred to the reactants within the reactor 100 as the rate of fiow of water through the reactor 100 increases.

Recapitulating, the apparatus 20 illustrated in FIG. 1 upon the establishment of the liquid stream and the gas stream threthrough and after closure of the switches 44 and 46 to provide operating potential between the electrodes and 130, is operative to produce essentially a spark discharge through and in the liquid stream and the gas stream within the reactor 100. The spark discharge liberates electrons and ions and in the presence of certain compounds also generates free radicals directly in the gas stream and the liquid stream so as to permit direct reaction with any reactants carried thereby. There also is generated electromagnetic radiation, sound energy and shear forces directly in the streams and for causing other physical and chemical actions upon any reactants carried thereby. In general, a more frequent and more intensive spark discharge is obtained with increasing gas stream flow rates, the gas stream serving to sweep the gap between the electrodes 120 and so as to continually renew the optimum conditions for the production of spark discharge therebetween. Conversely, increasing the liquid flow rate tends to decrease the spark discharge between the electrodes 120 and 130. It further is pointed out that large concentrations of energy can be present in the gas stream and liquid stream and imparted thereby by spark discharge, these concentrations of energy being on the order of 1 to 10 megawatts when the capacitors 85, the reactance of the power supply 30 and of the spark gap in the reactor 100 are adjusted to have a peak discharge of the capacitors at approximately a 1 megacycle rate. These high concentrations of energy, although having a very brief time duration, make possible unusual and desirable chemical and physical reactions within the reaction chamber 102.

The reactor 0 FIGS. 10 to 12 Referring to FIGS. 10 to 12 of the drawings, there is illustrated a third embodiment of the invention employing a reactor generally designated by the numeral 300. The reactor 300 comprises a generally rectangularly shaped block 301 that is formed of an electrical insulating material such as plastic, glass, ceramic or the like, and is preferably formed of a transparent or translucent synthetic organic plastic resin, preferably methyl methacrylate resin. The block 301 is provided with a centrally located reaction chamber 303 defining a reaction zone into which extend a pair of electrodes generally designated by the numerals 304 and 305. The electrodes are preferably formed of metal, the preferred metal being aluminum. The electrodes are provided with inner ends 304a and 305a, respectively, that are disposed Within the reaction chamber 303 and are spaced from each other a distance to insure a proper spark discharge therebetween when a suitable potential is applied between the outer ends thereof generally designated by the numerals 304b and 30511. The electrodes 304 and 305 are held in the proper adjusted position by means of two screws 306 and 307, respectively, which are threaded into the block 301, adjustment of the spacing of the inner ends 304a and 305a of the electrodes being possible by loosening of the screws 306 and 307 and subsequent tightening thereof after adjustment of the positions of the electrodes.

A number of passageways are provided through the block 301 all communicating with the reaction zone 303 for use in introducing liquid streams and gas streams thereinto. A first insulated pipe 308 is provided mounted in the body 301. having an opening therethrough communicating with the reaction chamber 303 through a restricted passage 312. The flow of material through the pipe 308 and into the reaction chamber 303 may be regulated by means of a needle valve 313 threadedly mounted in the body 301 and positioned to be moved into and out of blocking relationship with respect to the passage 312 so as to regulate the flow of material through the pipe 308 and into the reaction chamber 303. A second insulated pipe 310 is provided mounted on the block 301 and having an opening therethrough communicating with the reaction chamber 303 and through a restricted passageway 314. A needle valve 315 is provided to control the flow of material from the pipe 310 through the passage 314 and into the reaction chamber 303, the needle valve 315 having the exterior surface thereof threaded and in threaded association with the associated opening 301. It will be seen that the needle valves 313 and 315 can be threadedly moved with respect to the block 301 and with respect to the associated restricted passages 312 and 314, respectively, so as to control the flow of materials between the reaction chamber 303 and the insulated pipes 308 and 310, respectively. A third insulated pipe 309 is mounted on the block 301 and has an opening therein communicating with the reaction chamber 303; and a fourth insulated pipe 311 is mounted upon the block 301 and has an opening therethrough communicating with the reaction chamber 303.

The reactor 300 can be connected in the system illustrated in FIG. 1 of the drawings by making the suitable electrical, gas and liquid connections thereto. There is illustrated in FIG. 12 of the drawings a simplified and schematic illustration of another system incorporating therein the reactor 300 of FIGS. 10 and 11. The electrodes 304 and 305 are connected at their outer ends to conductors 316 and 317, respectively, which are also connected to the terminals of the secondary winding 318 of a power step-up transformer 319. The transformer 319 has a primary winding 320 which may be connected to any suitable source of operating potential such as a 110 volt 60 cycle A.C. source. A capacitor 323 is also connected between the conductors 316 and 317, the capacitor 323 being illustrated as of the variable type. If desired, the point on the secondary winding 318 of the transformer 319 may be grounded as illustrated.

The inlet pipe 308 is connected by a conduit 324 to the outlet 325 of a pump 326 which has an inlet 327 connected to a suitable source of gas, such as the atmosphere. Operation of the pump 326 draws air from the atmosphere and compresses it and forces it under pressure through the conduit 324 and the pipe 308 into the reaction chamber 303 of the reactor 301. The pipe 310 is connected to one end of a conduit 328 having the other end thereof connected to the outlet 329 of a pump 330 which in turn has an inlet 331 communicating with the contents of a tank 332 containing a liquid to be pumped into the reaction zone 303 of the reactor 300. The pipe 309 is connected to one end of a conduit 333 having the other end thereof connected to the outlet of an elevated tank 334 containing a liquid, a control valve 335 being provided in the conduit 333 to control the flow of the liquid from the tank 334 through the conduit 333 and the pipe 309 and into the reaction chamber 303. The pipe 311 is connected to an outlet conduit 336 which empties into a tank 337 for receiving the material fed through the reaction zone 303 of the reactor 300.

In the operation of the system illustrated in FIG. 12 of the drawings and incorporating therein the reactor 300, the pump 326 is actuated to cause a flow of pressurized air through the inlet pipe 308; the valve 335 is opened to permit flow of liquid from the tank 334 through the conduit 333 and the inlet pipe 309 into the reaction chamber 303. Having established the air stream and the liquid stream through the reactor 300, the operating potential can be applied to the transformer 319, specifically, to the terminals 321 and 322 thereof whereby to cause a high potential on the order of several thousand volts to be produced between the output terminals of the secondary winding 318 and between the conductors 316 and 317. With the position of the electrodes 304 and 30 adjusted with the proper potential applied therebetween from the conductors 3'16 and 317, respectively, and with the suitable air and liquid streams flowing through the reactor 300, a high voltage spark discharge is obtained between the electrodes 304 and 305 and within the reaction chamber 303 to impart energy to the materials carried by the various streams. The discharge is of the same general character and produces the same physical and chemical results discussed above in describing the apparatus 20 of FIG. 1. The treated liquid and gas streams flow from the reactor chamber 303, through the pipe 311 and the conduit 336 and are collected in the tank 337. A second liquid or a second gas can be fed through the pipe 310 by operation of the pump 330 to be mixed in the reaction chamber 303 with the liquid and gas streams described above. It further is pointed out that either gas or liquid can be introduced through any one of the pipes 308, 309, 310 and 311, it simply being required that at least one of the pipes be available as a discharge, so that three ditferent streams may be fed to the reactor 300 at any given time.

It is noted that the electrodes 304 and 305 are in axial alignment with one another, the inlet pipes 308 and 310 are in general axial alignment with each other, the inlet pipes 309 and 311 are in axial alignment with each other and all are converging toward the reaction chamber 303.

The reactor 0 FIG. 13

There is illustrated in FIG. 13 of the drawings a fourth embodiment of a reactor 400 made in accordance with and embodying therein the principles of the present invention. The reactor 400 includes a block 438 of suitable insulating material, preferably a synthetic organic plastic resin, the preferred resin being methyl methacrylate resin. Formed generally centrally of the block 438 is a reaction chamber 403 having passages 412 and 414 extending outwardly therefrom and toward the adjacent edges of the block 438. A first pipe 408 formed of insulating material is mounted on the block 438 and has an opening therethrough communicating through the passage 412 with the reaction chamber 403. A second pipe 410 formed of electrical insulating material is also mounted upon the block 438 and has an opening therethrough communicating through the passage 414 with the reaction chamber 403. A third pipe 409 formed of an electrical conducting material is mounted in the block 438 and has an opening therethrough communicating directly with the reaction chamber 403, the pipe 409 being connected to a conductor 416, whereby the pipe 409 serves as one of the electrodes for the reactor 400. A second electrode 460 is mounted in the block 438, the electrode 460 having an external surface thereof threaded and threadedly engaging a threaded opening in the lower portion of the block 438. The upper end 406a of the electrode 460 extends upwardly into the reaction chamber 403 and the spacing thereof from the lower end of the electrode 409 can be adjusted by threading the electrode 460 inwardly and outwardly with respect to the block 438. The lower end of the electrode 460 is connected to a conductor 417, it being understood that a suitable operating potential is applied between the conductors 416 and 417 during the operation of the reactor 400.

In the operation of the reactor 400, the pipe 408 receives either a gas or liquid therethrough for introduction into the reaction chamber 403; the pipe 409 receives therethrough a gas or liquid stream that impinges upon the gas or liquid stream from the pipe 408 within the reaction chamber 403. The streams within the reaction chamber 403 are exposed to the spark discharge established between the electrodes 409 and 460, in a manner similar to that described in detail above with respect to the apparatus 20 of FIG. 1. The reacted streams flow from the reaction chamber 403 through the pipe 410 and thus out of the reactor 400.

The reactor 0 FIGS. 14 and 15 Referring to FIGS. 14 and 15 there is illustrated an apparatus incorporating therein a fifth form of a reactor 500 made in accordance with and embodying the principles of the present invention. The reactor 500 includes a generally cylindrical body 540 formed of an electrical insulating material such as plastic, glass, ceramic, or

the like, and is preferably translucent or transparent, the preferred material of construction being a synthetic organic plastic resin, the preferred resin being methyl methacrylate resin. Formed centrally in the upper portion of the block 540 is a vertically extending opening 541 which receives therethrough a metal tube 542 that extends downwardly into a larger cylindrical opening 543 formed in the lower portion of the block 540 and downwardly beyond the lower end of the block 540 and into a metal end piece 546. The end piece 546 is gen crally cylindrical in shape and has an outwardly extending flange 560 around the upper end thereof that is held against the lower end 544 of the block 540 by an annular metallic sleeve 547 which is threaded at 561 and threadcdly engages the complementary threads on the exterior surface of the block 540 at the lower end thereof. Extending inwardly from the lower edge of the sleeve 547 is a flange 562 which engages thc flange 560 on the end piece 546 to clamp the end piece 546 to the lower end of the block 540. The lower end of the end piece 546 is generally closed by a wall 563 having an aperture 548 generally centrally thereof and in longitudinal alignment with the tube 542. The lower end of the tube 542 has a converging section thereon terminating in an orifice 549 that discharges into the end piece 546, and specifically into the reaction chamber 503 formed thereby and in alignment with the aperture 548 in the end piece 546.

Referring specifically to FIG. 14. it will be seen that the metallic sleeve 54'! has electrically connected thereto a conductor 516 and the metallic tube 542 has electrically connected thereto a conductor 517. A suitable operating potential is applied between the conductors 516 and 517 from a transformer 519, the transformer 519 specifically including a primary winding 520 connected to a suitable source of operating potential at the connections 521 and 522, a typical source being a ll() volt A.C. 60 cycle Edison supply. The transformer 519 is provided with a secondary winding 518 having the end terminals thereof connected respectively to the conductors 516 and 517 and having the center thereof grounded as illustrated. Also connected between the conductors 516 and 517 is a capacitor 523 which has been illustrated as being of the variable type. The power supply thus described is effective when operated to apply the necessary operating potentials between the tube 542 which serves as one of the electrodes for the reactor 500 and the sleeve 547 which is directly connected electrically to the metallic end piece 546 which serves as a second electrode for the reactor 500.

Mounted in the side of the block 540 is a pipe 550 having an opening therein communicating at one end with the opening 543 within the block 540 and at the other end communicating with one end of a conduit 551. The other end of the conduit 551 is connected to the outlet 552 of a pump 553, the pump 553 having an inlet 554 connected to the atmosphere, whereby the pump 553 is operative to draw air from the atmosphere, compress the air and discharge a stream thereof through the conduit 551 and the pipe 550 into the reaction chamber 503, the air stream thus produced flowing around the exterior of the tube 542 and then downwardly and outwardly through the aperture 548. The upper end of the tube 542 is connected to the lower end of a conduit 555, the upper end of the conduit 555 communicating with a tank 556 containing liquid to be conveyed to the reactor 500, the flow of liquid from the tank 556 being under the urging of gravity and being regulated by means of a valve 557 disposed in the conduit 555. By this construction, a liquid stream is established flowing through the tube 542 and outwardly from the lower end thereof through the opening 549 and into the reaction chamber 503 where the liquid stream is exposed to both the gas stream from the pipe 550 and the spark discharge between the tube 542 and the end piece 546. The treated liquid stream together with the gas stream exits from the end piece 546 through 20 the aperture 548 in a combined stream as at 559 and falls upon a suitable collector that is diagrammatically illustrated at 558 in FIG. 14.

The operating conditions for the reactor 500 are substantially the same of those for the reactor 100 described above, whereby materials in the gas stream and liquid stream flowing through the reactor 500 are subjected to the spark discharge taking place directly therein to cause the highly desirable physical and chemical reactions thereon.

Treatment 0 f starch The apparatus 20 of FIG. 1 incorporating the reactor 100 therein is particularly useful in the treatment of starch to modify the physical and chemical characteristics thereof. The following is a specific example of the treatment of corn starch utilizing the apparatus 20 of FIG. 1, the corn starch containing about 20% by weight amylose and the remainder being substantially amylopectin.

EXAMPLE 1 Pearl corn starch was slurried in cold water containing ammonium chloride and hydrochloric acid. Sufficient hot water at 150 F. was added to the slurry to Warm it to a temperature of 118 F., care being exercised not to permit the temperature at any time to reach the gelatinization temperature of the starch. The starch slurry as prepared had the following composition and characteristics:

Pearl corn starch21.6% by Weight Ammonium chloride4 grams per liter of slurry Hydrochloric acid (37% by weight)To provide a pH Temperature-118 P.

The resultant starch slurry was placed in the tank 92.

The power supply 30 was energized by closing the switch contacts 33-34 after which the pump start switch 46 was closed to energize the motor to start operation of the pump 94. The pump 94 was operated to deliver the starch slurry to the reactor at a rate of 0.6 gallon per minute. An air line was connected to the conduit 88 and the air regulator 90 was adjusted to permit air into the reactor 100 at a line pressure of 10 psi. as indicated by the gauge 91. The reactor start switch 44 was then closed to energize the relay coil 51 to close the contacts associated therewith and to apply operating potential to the various transformers in the power supply 30. A spark discharge was immediately produced between the electrodes and in the reactor 100. After the reactor had been running for several seconds, the tank 141 was placed in position to receive the product issuing from the pipe at the bottom of the reactor 100. The temperature of the stream entering the tank 141 was 122 F. The potential supplied to the primary windings of the step-up transformers 80A, 80B and 80C as determined by the volt meters 64A, 64B and 64C was 116 volts, the output from the secondary windings thereof was 12,000 volts whereby the potential applied to the electrodes 120 and 130 was approximately 9,000 volts; the capacitance of the capacitors 85 was 0.05 mierofarad and the current drawn as indicated by the ammeter 62A, 62B and 62C was approximately 20 amperes. The total reacted slurry in the tank 140 was then placed in an open container and air dried by blowing air thereover during a period of approximately 16 hours to provide the reacted starch product.

The reacted starch product differs in both its physical properties and its chemical properties from the pearl corn starch introduced into the reactor 100. For example, the apparent molecular weight as determined by the viscosity of potassium hydroxide solutions thereof is materially reduced by passing the starch through the reactor 100 as described above. More specifically, the apparent molcctu lar weight of the pearl corn starch before reaction is 21 approximately 1,148,500, whereas the reacted starch product has an apparent molecular weight of 294,620.

As utilized herein, the term apparent molecular weight refers to the value obtained by measuring the viscosity of potassium hydroxide solutions containing the starch or the treated starch, as the case may be. In making the determination of the apparent molecular weight, the starch product is first Washed with a 96% ethyl alcohol solution to remove the ammonium chloride therefrom. 0.2 gram of the starch product was carefully dissolved in 100 ml. of 1 molar aqueous potassium hydroxide solution. The efilux time in seconds of the solution from an Ostwalt-Fenske #50 or #100 viscometer as required Was determined. A relative viscosity was then obtained using the formula:

"lrel s/to wherein, I, is the efllux time of the unknown sample, t is the efilux time of the potassium hydroxide solution without any sample therein, and 1 is the relative viscosity. Because of the non-ideal behavior of the starch solutions, the relative viscosity is dependent upon the concentration of the starch therein. A viscosity number at infinite dilution is obtained by extrapolation of a plot of the relative viscosity numbers versus concentration of the starch in the solutions in grams per milliliter to yield the limiting viscosity number (or the intrinsic viscosity) in accordance with the following formula:

l ll LJ l1 7 ON] The limiting viscosity number is related to the apparent molecular weight (M) by the Staudinger equation:

where K and a are empirical constants for the starchsolvent system, the values for these constants in 1 molar potassium hydroxide being:

The above method is explained in further detail in Methods in Carbohydrate Chemistry, vol. 1V, P. L. Whistler, editor, Academic Press, Inc., New York, N.Y., 1964, pages 127 et seq., 179 and 180.

The reducing end groups present in the reacted starch product are considerably more numerous than those in the pearl corn starch that is the starting ingredient, the pearl corn starch having end groups corresponding to a ferricyanide reducing number of 0.5 as compared to a value of 15.0 for the treated starch product. The ferricyanide reducing number referred to herein is the figure obtained utilizing the method developed by Thomas J. Schoch of Corn Products Company, Argo, Ill. and reported in detail in Methods in Carbohydrate Chemistry, vol. IV, R. L. Whistler, editor, Academic Press, Inc, New York, N.Y., 1964, pages 6467. Briefly, the method consists in adding alkaline ferricyanide solution to a starch sample dispersed in water and digesting the mixture at a vigorous boil for 15 minutes. A zinc sulfate/ acetic acid solution is added for color control after which a 20% by weight potassium iodine solution in water is added. The iodine liberated by the reaction with the reducing end groups is titrated with 0.05 N standard sodium thiosulfate solution in Water. The milliliters of sodium thiosulfate solution required is directly proportional to the reducing end group content of the starch in accord ance with the following formula:

I for blank for sample thiosulfatc X It also has been determined that the apparent carboxyl content of the starch treated by the reactor is substantially greater than that of the original pearl corn starch, the original pearl corn starch value being sub stantially nil, and the value for the reacted corn starch of Example 1 above being 0.297. The method utilized in determining the apparent percent carboxyl" is that set forth in the article entitled Determination of the Carboxyl Content of Oxidized Starches by M. F. Mattisson and K. A. Legendre, in Analytical Chemistry, vol. 24, No. 12, December 1952, pages 1942-1944. This method in brief consists of first washing the chloride from the starch sample. The starch sample is then slurried with water and cooked for about 6 minutes to insure gelatinization. The hot, pasted starch is titrated with 0.1 N sodium hydroxide to the phenolphthalein end point. The apparent percent carboxyl" is attained from the following computation:

The amylose portion of the corn starch normally possesses a typical helical coil form which has a shape and characteristic such that when iodine is added to a slurry of the starch, the iodine is entrapped in the helical coil and imparts the characteristic blue color to the starch. The addition of iodine to an aqueous slurry of the starch product from Example 1 causes the typical blue color to be formed in the starch indicating that the helical coil form has been preserved. The iodine test also indictates that the starch is more fluffy and more flocculent and more dispersed than the untreated starch. Accordingly, the starch treatment in the reactor 100 although otherwise materially changing the physical and chemical characteristics of the starch, does not produce any significant destruction of the helical configuration of the amylose fraction thereof.

It will be understood that the various parameters and conditions set forth above with respect to Example 1 can be substantially changed without departing from the spirit and scope of the present invention. The concentration of starch in the slurry fed to the reactor 100 may be as little as 0.5% by weight and up to as much as 40% by weight, the only limitation being that the slurry must be capable of being transported by pumping through the reactor 100; the preferred concentration of starch in the slurry is about 20% by weight.

Although Example 1 illustrates the treatment of starch slurries having an acid pH, an acid pH is not necessary, and satisfactory operation of the reactor 100 has been obtained utilizing starch slurries having a pH in the range from about 1.0 to about 9.0. The acid range is generally from pH 1 to 6.5, the preferred pH lying in the range from about 1.5 to about 3.0. In the basic pH range, the preferred pH is from about 7.5 to about 9.0. Any acid is useful to create the desired acid pH that will react with the starch in the general temperature range from about 70 F. to about F. substantially only to hydrolyze the star-ch by chain sission. An example of the preferred mineral acid is hydrochloric acid, and an example of the preferred organic acid is acetic acid. Any desired base may be utilized to create a basic pH, the preferred bases being sodium hydroxide and ammonium hydroxide.

It further is desirable to buffer the starch slurry while it is in the reactor 100. When operating in the acid pH range, the preferred class of buffering agents are amines including ammonium ion, the lower aliphatic organic amines such as triethanolamine and amino acids. As illustrated in Example 1 above, a suitable buffering agent in the acid range is ammonium chloride, the concentration of the ammonium ion in the slurry being in the Weight; of sample on dry basis range from about 0.003 mole per liter to about 0.3 mole per liter, the preferred value as illustrated in Example 1 above being 0.075 mole per liter. When operating in the basic pH range, the preferred buffering agents are the oxides of boron, such for example, as sodium tetraborate. A desirable concentration of the borate in the slurry is in the range from about 0.003 mole per liter to about 0.3 mole per liter, the preferred concentration being 0.075 mole per liter. The amines and the borates are also thought to accelerate the action of the reactor 100. In addition it is believed that the ammonium ions may tend to stabilize any free radical reactions that are taking place in the reactor 100.

Starches can be treated in the temperature range from ambient temperature up to about 140 F., care being taken that there is no gelatinization of the slurry. The preferred operating temperature range is from about 110 F. to about 120 F.

The flow rate of the starch slurry through the reactor 100 can also be varied and may be as little as 0.05 gallon per minute and up to 1.5 gallons per minute, the preferred flow rate being on the order of 0.6 gallon per minute. The time that the slurry is subjected to the action of the spark discharge is inversely related to the How rate, i.e., at the slower flow rates there is a longer exposure time and at the higher flow rates there is a shorter exposure time. At the preferred flow rate of 0.6 gallon per minute, the exposure time is approximately 0.069 second, whereas at the slightly lower llow rate of 0.45 gallon per minute, the exposure time is 0.091 second, and whereas at the higher flow rate of 1.5 gallons per minute, the exposure time is 0.027 second.

The air pressure supplied to the reactor 100 during the treatment of the starch slurry can also be varied from that set forth in Example 1 above. A substantially lower pressure on the order of 5 p.s.i. can be used or substantially higher pressures on the order of 50 psi. or higher may be used. As has been pointed out heretofore the efiiciency of the transfer of energy to the spark discharge is increased at the higher air pressures, whereby an air pressure on the order of p.s.i. as indicated by the gauge 91 is preferred.

The operating potential applied between the electrodes 120 and 130 may be from about 4,500 volts to about 20,000 volts or higher, the preferred value being on the order of about 9,000 volts. In passing it is pointed out that despite the applied potential, the actual potential at which a discharge is obtained is determined fundamentally by the geometry of the reactor 100 and the characteristics, concentrations and conditions of the reactants flowing therethrough.

A wide variety of types of starch can be treated in the apparatus 20 of FIG. 1. In addition to the corn starch illustrated, starches from other seeds, roots and tubers can also be treated. All starches are fundamentally composed of a mixture of two polymers, amylose and amylopectin. Starches containing substantially no amylose, such as waxy maize, can be successfully treated in the apparatus 20 of FIG. 1. Furthermore, starches having higher appropriations of amylose may also be successfully treated, i.e., starches having more than 20% amylose content. For certain purposes, it is preferred that the starch slurry passing through the reactor 100 contain at least about 5% amylose by weight as will be ex plained more fully hereinafter.

Instead of only passing the starch slurry once through the reactor 100, it will readily be understood that a slurry can be repeatedly recycled through the reactor 100 by providing a suitable interconnection between the tanks 92 and 141. The chemical and physical properties of the starches are materially altered after multiple passes through the reactor 100, and there are illustrated in FIGS. 16, 17 and 18 of the drawings, changes in the various physical and chemical properties of the starches as a result of multiple passes through the reactor 100.

Referring first to FIG. 16, there is plotted thereon the relationship between the apparent molecular weight and the number of passes that the starch slurry makes through the reactor 100. The curve 160 plots the relationship between the apparent molecular weight and the passes through the reactor for corn starch wherein the process is carried out in accordance with Example 1 above. It will be seen that the apparent molecular weight generally decreases with additional passes of the starch slurry through the reactor 100, the apparent molecular weight for 1 pass being approximately 295,000, the apparent molecular Weight for 2 passes being approximately 220,000, the apparent molecular weight for 3 passes being approximately 216,000, the apparent molecular weight for 10 passes being approximately 151,000, and the apparent molecular weight for 15 passes being approximately 39,000. There also is plotted in FIG. 16 a curve 162 showing the effect of passing the same starch slurry of Example 1 through the reactor 100 but without applying the potential to the electrodes and so that no spark discharge occurs therein. It will be seen that the apparent molecular weight still decreases but not so rapidly as when the spark discharge is present, the molecular weight for 1 pass without spark discharge being approximately 386,000, for 2 passes being approximately 276,000, for 3 passes being approximately 256,- 000, for 10 passes being approximately 234,000 and for 15 passes being approximately 187,000. There further is plotted in P16. 16 the curve 164 which illustrates the effect of treating waxy maize starch in accordance with Example 1 above, it being pointed out that waxy maize starch contains substantially 100% amylopectin. Immediately upon being placed in the slurry for a period of time corresponding to 1 pass, the apparent molecular weight drops from the untreated value of 466,000 to a value of 18,000, this value being plotted as the pass value in FIG. 16 on graph 164. For 1 pass through the reactor 100 with the spark discharge present, the apparent molecular weight actually rises to about 24,000, and for 15 passes through the reactor 100 with the spark discharge present, the apparent molecular weight rises to approximately 49,000. Accordingly, it will be seen that in using the reactor 100 to treat a starch comprising esscntially 100% amylopectin, the apparent molecular weight substantially increases, whereby it is believed that the amylopectin fraction of the corn starch in the curve is likewise being acted upon to increase the apparent molecular weight, and accordingly, the amylose faction is believed to be acted upon fundamentally to decrease the apparent molecular weight thereof.

There is illustrated in FIG. 17 of the drawings a plot of the ferricyanide reducing number against the number of passes of the starch slurry through the reactor 1.00. There is plotted on the curve the ferricyanide reducing number for corn starch reacted in accordance with Example 1 above, and it will be seen that the terricyanide reducing number steadily increases with additional passes through the reactor 100. More particularly, the ferricyanide reducing number increases from a value of 15.0 for 1 pass to a value of 15.25 for 2 passes to a value of 16.15 for 10 passes and to a value of 19.0 for 15 passes. There is plotted on the curve 172 the ferricyanide reducing numbers obtained by carrying out the process of Example 1 but without applying the spark discharge to the starch slurry in the reactor 100. It will be seen that the ferricyanide reducing number generally decreases with additional passes of the starch slurry through the reactor 100, the value being 12.63 for 1 pass, 12.12 for 2 passes, 11.37 for 3 passes, 10.25 for 10 passes, and 9.87 for 15 passes. There further is plotted in FIG. 17 the curve 174 plotting ferricyanide reducing numbers for waxy maize starch treated in accordance with Example 1 above. Treatment with ammoniacal acid solution without passage through lhe reactor provides a ferricyanide reducing

Claims (1)

1. 46. THE METHOD OF MAKING PAPER COMPRISING THE STEPS OF PROVIDING A STOCK INCLUDING PAPER-MAKING FIBERS AND A STARCH DERIVATIVE CHARACTERIZED BY AN APPARENT MOLECULAR WEIGHT IN THE RANGE FROM ABOUT 35,000 TO ABOUT 350,000 AND A FERRICYANIDE REDUCING VALUE IN THE RANGE FROM ABOUT 14 TO ABOUT 20, FORMING A WET SHEET FROM THE STOCK, AND DRYING THE WET SHEET TO PROVIDE A FINISHED PAPER FORMED OF THE PAPERMAKING FIBERS AND CARRYING THE STARCH DERIVATIVE AS A SIZING THEREON.

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