US2363238A - Method of producing useful products - Google Patents

Description

Patented Nov. 21, 1944 METHOD OF PRODUCING USEFUL PRODUCTS Jacquelin E. Harvey, Jr., Washington, D. (3., and

Robert H. White, Jr., and Joseph A. Vaughan, a Atlanta, Ga., assignors of one-half to said Harvey, Jr., and one-half to Southern Wood Preserving Company, East Point, Ga., a corporation of Georgia No Drawing.

3 Claims.

The instant invention relates to the production I of toxic oils employable as fungicides, insecticides, and for any other service to which toxic oils may be put;

More especially the instant invention relates to the production of toxic oils from mixtures of petroleum fractions characterized by ring structure content. Among such starting materials may be mentioned mixtures of petroleum fractions characterized by ring structure content recovered from petroleum fractions by well known extraction methods including extractive distillation and azeotropic distillation. Also may be mentioned mixtures of petroleum fractions characterized by ring structure content as flowing from thermal and/or catalytic treatment of certain petroleum fractions which includes petroleum fractions having ring structures induced in the course of thermal and/or catalytic treatment, as for example having ring structures induced in the course of one or more thermal and/or catalytic treatments of unusual length, as for example, for periods of from 1-10 hours or more.

An object of the instant invention is the production of toxic oils from the aforenamed petroleum fractions or others whereby to provide oils of the preservative type, as for'example presservative wood impregnants conforming to specifications extant or acceptable to the trade consuming such oil materials.

Another object of the instant invention is the provision of preservative wood impregnants having boiling ranges and residues in accordance Application November 10, 1942, 1 Serial No. 465,166

Another object. of the instant invention is the maintenance of a preponderant proportion of the cyclic structures in the material undergoing induction in at least a methylated condition, it having been found that objectionable reaction products are formed if this object is not adhered to.

Another, object of. the invention is the control of saturates in specific fractions of the material of the beneficiated materialwhich is characterundergoing treatment.

Still another object of the instant invention is the control of the percentage of cyclic structures, as for instance aromatics, in specific fractions ized by induced toxic properties.

with published specifications and/or in accordance with consumer preference.

Another object of the instant invention is.the reforming, modifying, converting and/or transforming of the mixtures of hydrocarbons whereby to induce toxicity.

Still another object of the instantinvention is the induction of usable toxicity in the presence of a gas or gaseous mixtures.-

Another object of the instant invention is the unveiling of latent toxicity in mixtures of petroleum fractions having inherent but inhibited toxicity.

Yet another object of the instant invention is the provision in the overall beneflciated material of that percentage of newly induced fractions boiling below 210 C. which is conducive to the induction of toxicity in other fractions of the material under treatment.

Another object of the instant invention is a change in Specific gravity in the overall beneficiated material which is conducive to the induction of toxicity.

Another object of. the, coordination of process variables so as to provide specific gravities within definite limits in various fractions of the beneficiated material.

Another object of the instant invention is a coordination of process variables which will provide in various fractional parts of the beneficiated material cyclic structures with specific gravities falling within the limits hereinafter stated.

Another object of the instant invention is the induction of toxicity in the presence of catalytic materials adapted to favorably influence said toxicity induction.

Another object of the instant invention is the induction of additional toxicity into fractional parts of the once beneflciated starting material under specific controls of process variables.

In the past wood preservative oils of: the high temperature coal tar derived type have been employed in quantities greatly exceeding the total of all other wood preservative oils. From the instant invention is the standpoint of availability of said coal tar as the parent product of wood preservative oils, it is annually Produced in this country under normal conditions to the extent of five hundred million to six hundred million gallons. This quantity of coal tar is capable of yielding an amount of high- 1y effective wood preservative oil which would make this country self-sufllcient in its wood preservative requirements. However, due to the fact that when a wood preservative distillat (creosote) is recovered from coal tar there remains rent method of processing coal tar leaves much to be desired. The net result of this situation obtaming is that the coal tar distiller usually confines himself to that distillation recovery of creo sote which would correspond to the attending amount of pitch that he can market at a profit. Accordingly, over a period of years several hundred million gallons of creosote oil have been imported into this country. That such a situation should obtain is apparently a paradox in that we annually produce a quantity of high temperature coal tar which if processed to yield creosote would makeus self-suflicient in that requirement. A

, survey of this paradox is fully outlined in an address given by no less an authority than S. P. Miller, technical director, The Barrett Company, 40 Rector Street, New York city, before the Franklin Institute, Philadelphia, Pennsylvania, in December, 1932. The economics of coal tar have not materially changed since that-date.

In view of the apparent inability of the coal tar industry to provide national needs of wood preservative oils, a strong incentive is given to groups processing other types of oil to invade the lucrative wood preservative market. At the present time many types of aromatic oils are produced by the petroleum industry, and the high boiling oils of aromatic content produced by this industry have for several years been tested for their wood preservative efficiency.

By the term petroleum aromatic as used" herein and in the appended claims is meant to include mixtures of petroleum fractions characterized by cyclic content and includes specifically various forms and types of naphthenes found in various mixtures of petroleum fractions, as for example monocyclic and polycyclic naphthenes.

The so-called petroleum aromatics which includes the monocyclic and polycyclic naphthenes and unsaturated hydrocarbon. fractions have in the past been produced in very large quantities.

However, very little work has been done on these materials. Such a fact is borne out on page 667, Reactions of Pure Hydrocarbons. Gustav Eglofi, Reinhold Publishing Corporation, 330 West 42nd Street, New York city, which states:

Despite the fact that naphthenes or cyclo-' tent produced (1940) at the Wood River reflnery of the Shell Oil Company and which has the following inspection:

Gravity 10.8 Flash, P. M. C. C ..FL. 295 Flash, C. 0. C F 290 Fixed carbon --per cent 4.9 Pour p in TL. -10 B. S. is W ..-per centby volume 0.1 S. U. vis. 100 F 151 S. U. vis. 210 F 41 S. F. vis. 77 F 34.5 Carbon res 6.8 Per cent aromatics and unsaturates 82.4 $01. in CS2 99.8 Loss 50 grams, 5 hours, 825 F 8.9 Residue of 100 pene per cent 37.5 A. S. T. M. distillation: r

I. B. P F.. 518 10% rec. F 565 20% rec. "F 589 rec. F 614 rec. "F 637 rec. F 660 rec. F 675 Maxlmum.

In the foregoing tabular data P. M. C. C. means Pensky- Martin Closed Cup; C. 0. 0. means Cleveland Open Cup.

Upon evaluating the foregoing oil forits tox icity to wood destroying fungi (Madison 517), it was found that this oil did not totally inhibit the growth of the fungi named at a concentra tion of up to and including 10%. v

It is now discovered that the oil above named or other'oils of cyclic content produced by the petroleum industry can be increased in toxicity in accordance with the process of the instant invention.

According to the instant invention oils of cyclic content produced by the petroleum industry are reformed, transformed, modified and/or converted to oils of a more toxic nature having characteristics acceptable to consumers of wood preservative impregnant and/or'conforming to wood preservative specifications extant.

The following examples will serve to illustrate several modes of practicing the present invention.

Example 1.-A mixture of petroleum fractions characterized by cyclic content and having but slight growth inhibition to wood destroying fungi, as for example the Shell product shown in the foregoing tabular data, is charged to a vessel adapted to operate-at superatmospheric pressure, as for instance at a pressure as high as several hundred atmospheres. The oil is brought up to a temperature of 4,40" C. where it is held in the commonly accepted liquid phase under a pressure of 750 pounds for such a length of time. as to provide 20% mewly formed materials boiling below 210 C.

At the end of the stated period the oil is with-- drawn from the processing chamber, cooled and inspected. Upon inspection the oil is found to have toxic properties unveiled as the result of the treatment above named, and such induction of toxicity flows from, among other things, the pro-' tions boiling below 210 c. are induced, latent toxicity is not unveiled to the desired extent.

210 C. are created, reactions 80 forward that are prejudicial to the induction of toxicity, as for example there occurs inordinate gasiflcation, inordinate production of undesirable fugitive materials and/or polymerization of high boiling fractions of the starting material under treatment.

To approximate commercial operating condiasoaass It has also been determined that if more than about 50% newly formed materials boiling below tions it is preferred to so control process vari icity diluents, inordinate gasiiication and/or-the formation of substantially non-toxic materials. The expression in at least a methylated condition. refers to the number of carbon atoms in the ring appendage or appendages. Each-fraction of the beneijlciated material of induced toxic properties, as for example and especially the material boiling between 315 C. and 355 C., has a preponderant proportion of materials of cyclic structure content present in at least a methylated condition.

Conditions that are prejudicial to the maintenance of'a preponderant proportion of the cyclic structures of the starting material in at least a methylated condition are excessive temperatures and/or excessive time of treatment. Temperatures that are employable in the instant process which will provide the aforenamed end result are selected between the limits of 350-550 C., and preferably between 425-475 0., say 440 C. or 450 C. Using the preferred temperatures-whilst operating at superatmospheric pressure, as for example at pressures selected between 200-2000 pounds, it will be found that when the treatment is carried on for a period of. one ortwo hours the end product will have induced toxicity as flowing from (1) a percentage of newly formed fractions boiling below 210 C. falling between the limits of controls above disclosed may be used in toto as a wood preservative or in the event it is desired to provide a wood preservative impregnant complying with speciflcations extant or of consumer preference, a wood preservative may be segregated from the overall beneflciatedoil as a stabilized residual, distillateor extract and in the event the extract has non-permissible low boiling ends, the extract maybe stabilized, to the,

necessary or desired extent. As examples of wood preservative impregnants of the oil derived type that are meeting with consumer acceptance, the following tabular data show several published specifications:

. is 450 C. and the pressure 750 pounds.

W001! PRISIBVATIVI TKPRIGNANTS Specifications 1. American Wood Preservers Association a. Up to 210 0., not more than 5% b. Up to 235 0., not, more than 25% 2. American Wood Preservers Association 41. Up to 210 (2., not more than 1% b. Up to 235 C., not more than 10% 0. Up to 355 0., not less than American Wood Preservers' Association a. Up to 235 0., not more than 1%% .b. Up to 300 0., not more than Mi /2% 0. Up to 355 0., not less than 45% American Wood Preservers Association a. Up to 210 C., not more than 8% b. Up to 235 C., not more than 35% American Wood Preservers Association :1. Up to 210 (3., not more than 10% 11. Up to 235 0., not more than 40% 6. American Wood Preservers Association it. Up to 210 C., not more than 5% b. Up to 235 0., not more than 15% Prussian Ry.

a. Up to 150 C., not more than 3% b. Up to 200 0., not more than 10% c. Up to 235 0., not more than 25% 8. National Paint Varnish 8: Laquer Association a. 5% at 162 C. b. 97% at 270 C. 9. Southern pine shingle stain oil a. 5% at 137 C. b. at 257C. Neville shingle stain oil a. I. B. P., C. b. 5% at 205 C. c. 95% at 292 C.

11. Carbolineum 270" c., I. B. 1?.

Example 2.-.Referring specifically to the overall beneflciated material of induced toxic properties produced by the process controls ,ofExample 1, it is found that the materials boiling below andabove 270 C. have relatively high and low toxicities, respectively. It is discovered that additional toxicity may be induced into the ben- 4 material is subjected to another toxicity inducingcycle in the liquid phase wherein the temperature The treatment is continued for a period of 45 minutes. The stated period is illustrative only. The retreatrnent period is desirably that which provides in the finally re-beneficiated material less than 50% newly formedrnaterials boiling below 210 0., including fixed gas or gases, based on the starting material. At the end of the stated L period the retreated material is withdrawn from its treating enclosure, cooled and inspected. Upon inspection the oil is found to have toxic properties in excessof the-overall once beneficiated oil and it is also determined that the finally beneflciated material yet maintains a preponderant proportion of thecyclic materials in at least a methylated condition.

The material flowing from the second toxicity induction may be in its overall state as a preservative wood impregnant, or if desired a specification wood preservative insofar as boi1- ing range is concerned may be segregated therefrom.

In lieu of retreating the entirety of the once beneficiated material at. a more elevated temperature only a portion thereof may be retreated in liquid phase and certain definite toxicity increases and benefits will flow therefrom, as for instance by retreating in liquid phase only the materials of relatively low toxicity boiling above 270 C. The retreatment of the materials boiling above 270 C., or a portion thereof, may be effected at the same temperature as the initial treatment, or if desired at a higher temperature. When the materials of relatively low toxicity are retreated for toxicity induction at either of the temperatures aforenamed, the retreated material when commingled with that portion of the starting material once .beneficiated,- will provide a comminglement having toxic properties in excess of those of the once treated oil.

Instead of commingling the entirety of the once treated materials and the twice treated materials, only a portion .thereof may be commingled provided the comminglement furnishes an oil'conforming in boiling range to consumer acceptance or provides a comminglement from which may be segregated an oil of consumer acceptance.

Example 3.Another mode ofpracticing the instant process whereby to induce toxicity resides inthe control of saturates in the materials boiling above 270 C. in the beneficiated oil, as for example the material boiling between 270 C. and 355 C.

As stated in the foregoing,'it has been found that the materials boiling above 270 C. in the beneficiated oil have a relatively low toxicity as compared to materials boiling below that temperature. It is known that the unsaturates are amongst the, most toxic of oil substances. However, it is determined that if an'attempt is made to provide in the beneficiated oil of induced toxic properties, the entirety of the materials boiling above 270 C., as for example the materials boiling between 270 C. and 355 C., as unsaturates adverse reactions occur that are prejudicial to the induction of toxicity, as for example there occurs (1) inordinate gasification, (2) inordinate production of materials of relatively little toxicity, and/or (3) polymerized high boiling materials. j

When providing acceptable toxicity in the overall reformed, transformed, modified and/or converted oil, it has been determined that by holding the percentage of saturates in the materials boiling above 270 C., as for example in the materials boiling between 270 C. and 355 C., to less than 30% but more than 5%, and preferably not more than no operating ills such as named will occur, or if said ills do occur they are minimized.

In accordance with an illustrative control of process variables which provides induced toxic properties whilst yielding an oil having less than 30% but more than 5% saturates in the mateand, having 42% and 35.7% saturates, respectively, in the 270-315 C. and 315-355 C. fractions, is subjected to a liquid phase thermal treatment of 445 C. for a period of one hour whilst under a pressure of 2050 pounds. At the end of the named period of treatment the bene-. ficiated oil is discharged from its treating enclosure, cooled and inspected. The beneficiated oil has only 29.7% residue above 355 C. and it is determined that there is 23.3% and 12% saturates, respectively, in the 270-315 C. and 315-* The oil has toxic properties 7 355 0. fractions. that are more pronounced than the parent feed stock. During the course of treatment 19.2% of newly formed materials boiling below 210 C. were formed. A further inspection of the beneficiated material discloses that a preponderant proportion of the cyclic structures of the starting material were maintained in at least a methylated condition.

Example 4.-.An oil of cyclic content produced by the-petroleum industry having inherent but inhibited toxicity, and an initial boiling point of about 270 C., about 50% residue above 355 C. and 53% and 55.3% aromatics, respectively, in the 270-315 C. and 315355 0. fractions, is subjected to a liquid phase thermal treatment at a temperature of 430 C. at a pressure of 1500 pounds for a period of one hour'and 45 minutes. At the end of the named period the treated oil is withdrawn from the processing enclosure. cooled and inspected. It is found that between 15% and 25% newly formed fractions boiling below 210 C. have been created. The residual matters above 355 C. have been reduced by about 50%. The fractions 270-315 C. and 315- 355 C. have 72.7% and 82.7% aromatics, respectively. The overall material is characterized by toxic properties more pronounced than the starting material. v

It is well understood in the art that the aromatics, as for example aromatics having side chains not greater than the propyl group, are amongst the most toxic of oil substances. As stated in theforegoing the feed stock in the instant example has slightly more than 50% aromatics in the 270- 355 C. fraction. However, the aromatics present, due to their peculiar type, exhibit inhibited toxicity. It would then, therefore, appear reasonable to attempt to provide in the-finally beneficiated oil total 'aromaticity in the materials boiling between 270 C. and 355 C. in order to induce toxicity of a high order, and more especially it would appear reasonable to attempt to provide total aromaticity of a type exhibiting satisfactory toxic values. It is discovered, however, that if an attempt is made to provide in the beneficiated material the entirety of the materials boiling above 270 C., as

aromatics in the materials boiling above 270 C.

in the beneficiated oil, as for example the beneficiated materials boiling between 270 C. and 355 C., to more than 70% but less than 95%, and preferably not less than toxicity is induced in a commercial manner whilst relatively nontoxic aromatics are converted to more toxic aromatics with the added benefits that the operatinordinate gasificationf ing ills above mentioned are minimized or eliminated.

Viewed in one manner, it is indicated 'that an important phase of our toxicity-inducing invention resides in, among. other things, the cOnversion of the peculiarly typed petroleum aromatics into types that more nearly approximate the coal tar type aromatics, and the conversion is predicated on the-novel process controls disclosed throughout this specification.

The oil of the instant example, as stated in the foregoing, has toxic properties more pronounced than the parent feed stock and may be used in toto as a wood preservative impregnant. However, this phase of the instant invention, in any and all example, resides in the novel manner of inducing toxic properties without reference to the provision of specification oils. However, as also previously mentioned, specification oils maybe segregated from the overall beneficiation.

Example 5.Another mode of practicing the instant'process resides in controlling the specific gravity ofthe overall beneficiated material remaining finally liquid after the completion of impressed process variables. It has been found that if an oil mentioned in the foregoing characterized by inherent but inhibited toxicity is subjected to thermal conditions whereby to provide a beneficiated material finally remaining liquid having, as compared to the parent feed stock, an overall change in spegravity is preferably held between 0.020-0.10%.

cific gravity between 0.015-0.15, and preferably between 0.020-0.10, the material of the changed specific gravity has toxic properties more pronounced than the parent feed stock. This change intsspecific gravity is a valid test'for induced tox- 101 v The noted change in specific gravity which is conducive to the induction of toxic properties may be either up or down, as more fully disclosed and explained in the following:

An oil of induced cyclic structures produced by the petroleumindustry having a specific gravity of 0.968, characterized by inherent but inhibited toxicity, boiling preponderantly above 315 C. and with substantial residual matter above 355 C; is subjected to a liquid phase thermal treatment at a temperature of 435 C. whilst under a pressure of 1,000 pounds :for a period of two hours.

At the end of the named treatment pe-.

riod the oil is cooled and inspected and found to 4 have a specific gravity of 0.945 or a reduction in specific gravity of 0.023%. The overall beneficiated material has induced toxic properties and more than 10% but less than 50% newly'formed fractions boiling below 210 C.

According to this specific mode of operational controls and test in the instant example, theprocess variables are so coordinated as to cause a reduction in specific gravity falling between the limits of 0.015 and 0.15%, and preferably between 0.020% and 0.10%. Such a stated change in specific gravity has the effect of inducing and indicating the induction'of toxic properties into materials previously having inhibited toxic values.

The lowering of the specific gravity in the beneficiated material within the defines stated is critical within limits- Unless the overall specific gravity of the material under treatment is lowered by 0.015%, a certain unveiling of inhibited toxicity is sacrificed, and ii the overall specific gravity is lowered by more than 0.15%. inordinate gasification, production of fugitive materials of relatively low toxic value and/ or polymerization will occur.

To avoid or minimize these ,ills, and/or others, thereduction of specific In connection with the change in specific gravity of the overall starting material which results in the induction of toxicity, 9. modification of the process resides in raising the specific gravity of the material remaining finally liquid after impression of process variables by a percentage falling between the limits of 0.015 and 0.15, and pref.-

-erably between 0.020 and 0.10.

To illustrate this modification of the instant process an oil of cyclic content produced by the petroleum industry having relatively little toxicity, as for example a flashed residuum having a specific gravity of 0.927, is subjected to a liquid phase thermal treatment at a temperature selected between the limits of 450-500 C. whilst under a pressure of 1,000 pounds for such a period as to provide an overall beneficiated mate-.

, cyclic structure content produced by the petroleum industry having inherent but inhibited toxicity, boiling 17% at 315 C., and about 50% residual matter above 355 C., is charged to a high pressure autoclave and subjected to a liquid phase thermal treatment. at a temperature selected between 425-475 C. whilst under a pressure of 1800 pounds for such a time as to jointly provide more than 10% but less than 50% newly formed fractions boiling below 210 C. and an overall specific gravity in fractional parts of the beneficiated material falling between the limits noted in the following tabular data:

Fractions Low limit High limit and preferably between the limits noted below:

Fractions Low limit High limit When processing the named oil and operating at a pressure and temperature of 1800 pounds and 440 C., respectively, a period of about one and one-half hours will provide a specific gravity in concentration for a giv growth inhibition of wood destroying fungi than the starting material.

The overall beneficiated oil may be used as a preservative wood impregnant, or there may be segregated therefrom an oil complying with specifications extant, as for example an oil complying with' the boiling range of a carbolineum type preservative oil, which in some instances boils almost entirely above 270 C.

The specific gravity of fractional parts of the v beneficiated material noted in the foregoing are critical within limits. Unless the lower limit is approximated toxicity induction will be unsatisfactory. If the high limit is.exceeded adverse reaction conditions will obtain, as for example there will occur inordinate gasification and/or production of highly polymerized and objectionable materials.

In lieu of inducing toxicity whilst providing operational control of the overall specific gravity of fractional parts of the beneficiated material as heretofore disclosed, the control may be directed to the provision of specific gravities of materials of cyclic structure content in fractional parts of the beneflciated material.

As an example, an oil of cyclic structure content produced by the petroleum industry having inherent but inhibited toxicity, no substantial percentage of fractions boiling below 270 Grand within excess of 40% residual matter above 355 C. is heat treated in the liquid phase at a temperature selected between the limits of 435-465" C. whilst under a pressure of 1500 pounds for such a length of time as to jointly provide more than but less than50% newly formed fractions boiling below 210 C. and a specific gravity of materials of cyclic structure content in fractional parts of the beneficiated material falling between the limits noted in the following tabular data:

Fractions Low limit High limit Fractions ni h limit When processing the named oil at a pressure and temperature of 1500 pounds and 450 C., respectively, a period of about one hour and minutes will provide a specific gravity of materials of cyclic structure content in fractional parts of the beneficiated material falling between the stated preferred limits.

When the beneflciated material is inspected it is found to have toxic properties more pronounced than its parent material.

The specific gravity of materials of cyclic struc ture content in fractional parts of the beneflciated material noted in the foregoing are critical within limits. Unless the lower limit is approximated, toxicity inductionis sacrificed. If the high limit is exceeded adverse reactions that are conducive to polymerization will occur.

Example 7.-A mixture of petroleum fractions characterized by cyclic content and having intime as to provide about newly formed fractions boiling below 210 C.

At the start of the processing period, or at any water gas, hydrogen or a'hydrogen containing gas may be employed, as for example methane or its homologues, including various refinery gases. About an hour and 15 minutes under .;the

.stated process variables will serve to provide-,the

stated percentage of newly formed fractions boiling below 210 C. At the end of thestated period the oil ,is withdrawn from the processing chamber, cooled, purged of its occluded gases, if any, and inspected. Upon inspection the oil is found t0.have toxic properties unveiled as the result of the treatment above named, and the unveiling of the toxicity flows from, among other things, the presence of the water gas and the provision of a percentage of newly induced fractions boiling below 210 C. falling between the limits of 10-50%, which in this specific example is about 20%.

Inspection of the beneficiated material discloses that a preponderant percentage of the cyclic structures of-the materials under treatment have been maintained in at least a methylated condition.

Example 8.- An oil-of cyclic content produced by the petroleum industry having inherent but inhibited toxicity, boiling preponderantly above 315 C. and having in excess of 45% residual matter above 355 C., is charged to an autoclave and waste refinery gases forced therein to an upper limit of 800 pounds. The starting material is then brought up to a temperature of 440 C.

and held in liquid phase under the generated pressure for a period of two hours.

At the end of the named period the material is cooled and inspected and is found to have more than 10% but less than newly formed fractions boiling below 210 C. It is determined that the beneficiated material requires a smaller concentration for a given growth inhibition of wood destroying fungi than the starting material. Further inspection discloses that a preponderant percentage of the materials of cyclic structure and held in liquid phase at that temperature for a period of one and one-half hours. At the end of the named period the treated oil is discharged, cooled, purged of its occluded gases, if any, and inspected. Inspection discloses that (1) toxicity is more pronounced than in the parent material, (2) more than 10% but less than 50% newly formed fractions boiling below 210 C. have i been created, and (3) a preponderant proportion of the materials of ring structure content have Eieen maintained in at least a methylated condi- The percentage of water noted above is illustrative only. Varying percentages may be employed, and in like manner the pressure of the carbon monoxide may vary. The' major and critical requirement is that the water be present to provide during reaction nascent hydrogen Example 10.A furfural extract of a mixture of high boiling petroleum fractions, said extract boiling preponderantly above 315 C., having substantial residual matter above 355 C. and inherent but inhibited toxicity is charged to a high pressure autoclave and nitrogen pumped in to anconditions available overall beneflciated material of induced toxic properties produced by the process controls of Examples 7-10 inclusive, it is found that the beneficiated materials boiling below and above 270 C. have relativelyhigh and low toxicity, respectively. It is discovered that additional toxicity may be induced into the beneficiated material by subjecting same to another liquid phase toxicity inducing cycle in the presence of an extraneous gas at a higher temperature than obtained in the first cycle of toxicity induction provided the retreatment yet maintains a preponderant proportion of the materials of ring struc ture content in at least a methylated condition.

Accordingly, the overall beneficiated material characterized by induced toxic properties as flowing from thermal treatment in the presence of an extraneous gas is subjected to another liquid phase toxicity induction in the presence of an extraneous gas, as an example, but not as a restriction, hydrogen, at a temperature of 465 C. and a pressure of 1800 pounds. The treatment is illustratively continued for a period of'45 minutes. The treated material is cooled and inspected and found to have toxic properties more pronounced than the overall once beneficlated oil, and it is determined that the finally beneficiated oil yet maintains a preponderant proportion of the cyclic materials in at least a methylated condition. x

The period of retreatment may vary over wide limits, but is preferably held at that period which provides in the retreated materials less than 50% newly formed materials boiling below 210 C., as compared to the parentfeed stock.

' In lieu of retreating the entirety of the once beneficiated oil in. the presence of an extraneous gas at a more elevated temperature, only a portion thereof may be retreated in the liquidphase and certain definite toxicity increases and benefits will fiow therefrom. l

Another. mode of inducing additional toxicity into the once beneficiated oil which has been treated in the presence of an extraneous gas is by retreating in the liquid phase in the presence of an extraneous gas only the materials of relartively low toxicity boiling above 270 C. Theretreatmentof the materials boiling above 270 C., ora selected portion thereof, may be effected at the same temperature as the initial treattures aforenamed, the retreated material when commingled with that portion of the starting material once beneficiated will provide a comminglement having toxic. properties in excess of the once treated oil. In lieu of eommingling the entirety of the materials once and twice treated in the presence of an extraneous gas, only a portion thereof may be commingled provided the comminglement furnishes an oil conforming in boiling range to consumeracceptance or provides a comminglement from which may be segregated an oil of consumer acceptance. 0

Example 12.-A liquid sulfur dioxide extract of a mixture of petroleum lubricating fractions boiling preponderantly above 315 C. and havin more than 30% saturates in materials boiling up to 355 C., is charged to a high pressure vessel and heat treated in the liquid phase in the presence of hydrogen at a temperature of 455 C. whilst under a pressure of 1800 pounds for such a period as to jointly provide more than 10% but less than 50% newly formed fractions boiling below 210 C. and less than 30% but more than 5% saturates in thematerials boiling between 270 C. and 355 C. Periods of from one to two hours under the stated conditions of temperature and pressure will illustratively serve to jointly provide the stated percentage of newly induced fractions boiling below 210 C. and the named percentage of saturates in the 270-355", C. fraction.

By controlling the percentage of saturates in the named fraction as stated, toxicity is induced with the added benefit that polymerized high boiling fractions are minimized or eliminated.

The beneficiated oil may be used in toto as a wood preservative impregnant or a segregation may be secured therefrom boiling in accordance with specifications noted elsewhere herein,

Example 13.-An oil of cyclic structure content. produced by the petroleum industry boiling preponderantly above 315 0., having subment, or. if desired, at a higher temperature,

When the materials of relatively low toxicity areretreated-in the presence of an extraneous gas,

for toxicity induction at either ofthe tempera- 76 stantial residual matter above 355 0., less than 70% aromatics in the materials boiling between 270. C. and 355 C. and inherent but inhibited toxicity is heat treated in the liquid phase in the presence of a hydrogen containing gas at a temperature and pressure of 460 C. and 1500 pounds, respectively, for such a period as to jointly provide more than 10% but less than 50% newly formed fractions boiling below 210 C. and more than 70% but less than arematics in the materials boiling between 270 C. and 355 C. In this instance a period of. one and one-half hours will illustratively serveto provide the stated characteristics in the beneficiated material.

Upon the completion of the treating period,

the oil is cooled, inspected and found to have a toxicity more pronounced than the starting material and for some purposes is employable in toto as a preservative wood impregnant. As

taught in the foregoing; desired segregations of the overall beneficiated material may be provided as specification impregnants.

Example 14.An oil comparable to the Shell oil shown in the foregoing tabular data having a specific gravityof 0.965, 16% boiling at 315 C., 47% residue above 355 C. and inherent,

but inhibited toxicity, is charged to a high pressure autoclave and heat treated in the liquid phase in the presence of hydrogenata temperature of 450 .C. whilst under a pressure of 2050 pounds for such a period as to reduce the stock.

conditions of temperature and pressure a ,pe-

riod of one hour and minutes will illustra-. tively serve to provide the named specific gravity.

At the end'of the named period the oil is cooled and inspected and found to have induced toxic properties. The overall beneficiated material is stabilized. to provide a'residual as an 7 gravity falling between the limits of 0.020% and- 0.10% is preferred as heretofore stated. Such a stated change in specific gravity has the effect of inducing toxic properties into materials previously having inhibited toxic values. The lowering of the specific gravity in the beneficiated material within the defines stated is critical within limits. Unless the overall specific gravity of the material under treatment is lowered by 0.015%.a certain unveiling of toxicity is sacrificed, and if the overall specific gravity is lowered by more than 0.15%, inordinate gasifica-- tlon, production of fugitive materials of relatively low toxic value and/or polymerization will occur. To avoid or minimize these ills, and/or others, the reduction of specific gravity is preferably held between 0.020 and 0.10%.

With further reference to the change in specific gravity of the raw feed stock which results in the unveiling of toxicity, a modification of the process resides in raising the specific gravity of the material remaining finally liquid after impression of process variables by a percentage falling between the limits of 0.015 and 0.15%, and preferably between 0.020 and,0.10%.

To illustrate this modification of the instant 'process, an oil of cyclic content produced by the petroleum industry having relatively little toxicity, as for example a flashed residuum having .aspecific gravity of 0.920 is subjected to a liquid phase thermal treatment in the presence of a hydrogen containing gas at a temperature selected between the limits of 430-500 C. whilst under a pressure in excess of 500 pounds for such a period as to provide an overall beneficiated oil remaining finally liquid having a specific gravity of 1.015. A period of from one to ten hours, dependent upon the temperature selected, will illustratively serve for the stated increase of specific gravity. 1

The oil of the stated increased specific gravity is inspected and found to have toxic properties more pronounced than its parent feed Example 15.An oil containing materials of cyclic structure content produced by the petroleum industry, having inherent 'but inhibited toxicity, boiling 17% at 315 C. and about 50% residual matter above 355 C., is charged to a high pressure autoclave and subjected to a liquid phase thermal treatment in the presence of hy-' drogen at a temperature selected between the limits of 425-500 C. whilst under a pressure of 2,803,238 overall specific gravity to 0.943. Under'the stated 1800 pounds for such a time as to jointly provide more than 10% but less than newly formed fractions boiling below 210 C. and an overall specific gravity in fractional parts of the hemeficiated material falling between the limits noted in the following tabular data:

Low limit at the stated pressure and a temperature of 460 0., a period of about one and one-half hours will provide a specific gravity in fractional parts of the beneficiated oil falling between the preferred limits and the stated percentage of newly formed materials boiling below 210 C.

The overall beneficiated oil is inspected and found to have unveiled toxic properties as shown by the fact that it requires a smaller concentration for a given growth inhibition of wood destroying fungi than the parent feed stock.

The entirety of the beneficiated material may be used as a preservative wood inpregnant, or there may be segregated therefrom an oil complying in boiling range with. published specifications, consumer preference or acceptance.

The specific gravity defines of overall frac-' tional parts of the beneficiated oil' of -induced toxic properties noted in the foregoing tabular data are critical within limits. Unless the lower limit is approximated, possible unveiling of toxicity will besacrificed. If the high limit is exceeded adverse reactions will obtain, as forexample there will occur inordinate gasification, inordinate production of fugitive materials of relatively low toxic value and/0r production of highly polymerized and objectionable materials.

Instead of inducing toxicity whilst providing operational control of overall fractional parts of the beneficiated material as heretofore disclosed, the operational control may be directed to the specific gravities of materials of cyclic struc-' ture content, as for example aromatics, in fractional parts of the beneficiated oil.

To illustrate this mode of operational control,

an oil of cyclic structure content produced by the petroleum industry having inherent but inhibited toxicity, no substantial percentage of fractions boiling below 270 C and with in excess of 30% residual matter above 355 C. is heat treated in the liquid'phase in the presence of a hydrogen containing gas at a temperature selected between the limits of 425-500 C'. whilst; under a pressure of 2,000 pounds for such a length of time as to jointly provide more than 10% but less than 50% 'newly formed materials boiling below 210 C., and a specific gravity of materials of cyclic structure content, as for example aromatics, in fractional parts of the benaseaase eficiated oil falling between the limits noted in the following tabular data:

When processing the named oil at the stated pressure and a temperature of 460 C., a period of about one, hour and 15 minutes will illustratively provide a specific gravity of materials of cyclic structure content, as for example aromatics, in fractional parts of the beneficiated oil falling between the stated preferred limits.

Upon inspection it is determined that the beneficiated material requires a smaller percentage for a given growth inhibition of wood destroying fungi than the crude starting stock.

The specific gravity defines of materials of cyclic structure content, as for example aromatics, in fractional parts of the beneficiated oil noted in the foregoing tabular data are critical within limits. Unless the lower limit isapproximated, toxicity induction is sacrificed. If the high limit is exceeded adverse reactions will occur that are conducive to inordinate gasification, inordinate production of fugitivematerial's of relatively low toxic value and/or polymerized products having objectionable characteristics.

Various catalysts assist in the reforming, transforming, modifying and/or converting of the starting petroleum oils whereby to provide materials of induced toxic properties. lysts are employable either in the material remaining liquid under process controls, or in the evolved vapors, or both. Among such catalysts may be mentioned the various metals, their oxides, sulfides and carbonates; cellulosic materials and carbon, activated or otherwise. Various silicious materials including the various clays shaped in appropriate form may also be employed. Various synthetic gels, as for instance the Well known hydrogels may also be employed as catalytic materials including specifically gelatinous precipitates properlyprepared. Also employable as catalytic materials are halogens, halids and derivatives thereof including specifically substitution and addition products thereof, as for example and specifically substitution and addition products of said derivatives, say a hydrogen halid.

The temperatures of the instant process are These cataselected between the limits of 350-550 C., and

preferably between 425-500" C. The pressures employed in the instant process are in excess of por phase operation which employs vaporized materials only.

If desired, insteadof subjecting the entirety of the feed stock to a single toxicity inducing operation, theparent material may be segregated into a plurality of cuts and these plurality of cuts subjected to separate toxicity inducing operations wherein the-temperatures in each instance are dissimilar, as for example, but not as a restriction, subjecting the highest boiling cut to the lowest temperature, etc.

In the example shown in the foregoing, one or more phases, etc., of one example may be added to or substituted for other phase or phases in another example where the substitution or addition is obviously workable.

The evaluation of the materials of cyclic structure content and/or aromatics referred to in the foregoing is secured by recourse to the method disclosed under the caption Neutral oils of coal hydrogenation-Action of sulfuric acid," Indus trial and Engineering Chemistry, volume 32, page 1614 et seq., December, 1940. Many modes of practicing the instant process "are possible. As for example the oils of inherent but inhibited toxicity mentioned in the foregoing may be subjected to a destructive distillation under pressure and toxicity induced therein. The following disclosures will enable those skilled in the art to practice such a process, and at the same time adding details which will immediately suggest themselves as routine and non-inventive improvements.

If desired, a mixture of petroleum fractions characterized by cyclic content, as for example the Shell product shown in the foregoing tabular data, having inherent but inhibited toxicity is charged to a still adapted to operate at superatmospheric pressure which communicates with a condenser. Intermediate the still and the condenser is an appropriate needle valve adapted to regulate the pressure within the still due to the pressure of evolved vapors. The still is so arranged that evolved vapors are at least partially refluxed. The reflux ratio may vary over wide limits and different effects flow from varying percentages of reflux. Air is excluded from the still during the preliminary heating period and the needle valve then closed so as to develop the desired pressure within the still due to the pressure of evolved vapors. The needle valve is then partially opened, and the valve aperture, heat control and reflux so coordinated as to provide a relatively constant flow of evolved vapors through the needle valve aperture.

Operating at a pressure of, as an example, a

'few hundred pounds or higher, it is found that the oil under distillation is reformed, transformed, modified and/or converted and toxicity induced therein. It is also found that the temperature necessary for the distillation of any given percentage of the feed stock is considerably higher than for the distillation of a comparable percentage under substantially atmospheric pressure.

As the distillation proceeds the temperature is gradually raised so as to maintain a relatively constant flow of distillate.

The distillation is carried to the desired extent, as for example for the distillation reforming of or more of the feed stock, or'the distillation may be carried to the greatest extent possible.

The time necessary for the distillation of a given charging stock will be "determined by the speed of firing, percentage of reflux, etc., and the process may be illustrated by recovering 3-10% of the still charge per .hour as materials of induced toxic properties.

If desired, the distillate may be redistilled under similar destructive distillation conditions to provide additional toxic properties.

Hydrogen, hydrogen containing gases, materials yielding hydrogen, or hydrocarbon gases may be employed within the still during the destructive distillation operation.

Minor changes within the scope of the ap-' pended claims may be made without departing from the spirit of the invention.

We claim:

1. The process of inducing toxicity into a petroleum [derived material characterized by substantial content of cyclic structures, WhiCh'OOmtemperatureselected between the limits of 350- 550 C. and pressure in excess of atmospheric; unveiling toxicity in the material under treatment by continuing the named cracking operation for a period not in excess of about two hours, the period being so selected with reference to the chosen temperature and pressure as to jointly provide a percentage of newly induced materials boiling below 210 C. falling between the limits of about 10-50% and an overall beneficiated material containing fractional parts having a .specific gravity falling substantially between the limits noted in the appended tabular data:

7 whereby to provide a material of induced toxic properties; and segregating from the beneficiated material an oil of the wood preservative type boiling preponderantly between 210 C. and 355 C., said oil characterized by induced toxic properties and substantial residual matter boiling above 315 C.,"the fractions of which have specific gravities falling between the limits above named.

2. The process of inducing toxicity into a petroleum derived material characterized by substantial content of cyclic structures, which comprises: subjecting a' mixtureof petroleum fractions boiling preponderantly above 270 C., characterized by a substantial percentage of relatively non-toxic materials boiling above 315 C., ring structure content and inherent but inhibited toxicity to liquid phase cracking conditions in the presence of a protective gas of extraneous source at a temperature selected between the limits of 350-550 C. and pressure in excess of atmospheric; unveiling toxicity in the material under treatment by continuing the named cracking operation for a period not in excess of about two hours, the period being so selected with reference to the chosen temperature and pressure as to Fractions Low limit High limit 0210 C 0. 710 0.9727 210-235 C 0. 801 1. 0048 235-270 C 0. 850 1.0315 270315 C 0. 914 1.0691 315355 C 0. 973 1. 1175 whereby to provide a material of induced toxic properties; and segregating from the beneficiated material an oil of the wood preservative type boiling preponderantly between 210 C. and 355 C., said oil characterized by induced toxic properties and substantial residual above 315 cific gravities falling between the'limits above named.

3. The process of inducing toxicity into a petroleum derived material, which comprises: subjecting a mixture of petroleum fractions boiling preponderantly above 270 C., characterized by'a substantial percentage of relatively non-toxic materials boiling above 315 C., ring structure content and inherent but inhibited toxicity to liquid phase cracking conditions at a temperature selected between the limits of 350-550 C. and a pressure in excess of atmospheric; unveiling toxicity in the material under treatment by continuing the named cracking operation for a period not in excess of about two hours, the period being so selected with reference to the matter boiling chosen temperature and pressure as to jointly provide a percentage of newly induced materials an dverall specific gravity between 0.973 and boiling below 210 C. falling between the limits of about 10-50%, and an overall beneficiated material containing fractional parts having a specific gravity falling substantially between the limits noted in the appended tabular data:

Fractions Low limit High limit 235-270 o-.. 0.850 1. 0315 2703l5 O--. 0. 914 1. 0691 315-355 O 0. 973 1.1175

whereby to provide a material of induced toxic properties; and segregating from the overall material an oil ofthe wood preservative type characterized by induced toxic stantial residual matter above 315 C. and boiling preponderantly between 210 C. and 355 C., the fraction 270-31590. of which has an overall specific gravity between 0.914 and 1.0691; and the fraction of which boiling between 315-355" C.nhas

' JACQUELIN E. HARVEY, JR.

ROBERT H. WHITE, JR.

JOSEPH A. VAUGHAN.

C., the fractions of which have speproperties, having .sub- 1