US1684125A - Atomizable mobile fuel product - Google Patents

Description

Patented Sept. 11, 1928,-

ouirso s'm res; PATENT ARTHUR w. BU'RWELL; or nine-ARA FALLS, NEW YORK, ssrenoa TOALOX CHEMI- can conrona'rron, or new 201m, n. :Y.,'-A oonPonA'rIon or NEW YORK.

n'roivirzlinnn HMOBJQILE FUEL rnon oo'r.

Ho Drawing;

i This invention relates to an atomizable mobile fuel product of the type consistmg essentially of finely divided SOllCl fuel dis-' persed in a normally liquidrfuel and held in a state of substantially stable suspension therein by means of a stablizing agent, and

to an economical process of making the same.

tion having a higher fuel value per unit volume than fuel oil alone previously have I led to attempts to utilize powdered solid fuel mixed with, or dispersed in, liquid fuel. It wasearly found that finely divided solid fuel (e.- g.', powdered coal) settles out of an intimate admixture of the same :with fuel economical mechanical agitation means. '25

Previous investigators have attempted to 7 stabilize the suspension of finely divided solid fuel in liquid fuel by the admixture therewith of rosin compounds, lime-rosin grease, coal distillates, gelatin, albumen, soaps and the like. Relatively stable suspensions have been prepared by the use of one or more ofthese stabilizing agents in the powdered solid fuel-fuel oil mixtures, articularly in those cases where the solid uel particles have been reduced to a substantially colloidal size in the presence of the liquid fuel and of the stabilizing agent. Such fluid fuel compositions, while exhibit? ing remarkable colloid-like properties with regard to the stability of the suspensions, are not of commercial use because of the high costs entailed in their preparation.

An object of the invention is to provide an atomizable mobile fuel product having the said desirable characteristics, and which may be prepared in such an economical manner that the product may compete commercially with powdered coal. r

The invention is based-upon my discovery of the fact that a petroleum soluble, nonaqueous mobile colloidal gel may be produced from a normally liquid petroleum hydrocarbon mixture such as the petroleum distillates commonly used as'fuel-and' known generally as fuel oils, by dissolving there- I a suspension. The many obviousiadvantages to be derived from the use of a mobile-fuel compos1-" App1ication filed lllarch 2, 1927. Serial ,No. 172,214.

in an alkali metal salt of a saponifiable, organic acidic product obtained by the controlled oxidation of a normally liquid aliphatic hydrocarbon, and that finely divided solidffuel, when dispersed in said etroleum soluble, non-aqueous mobile colloi a1 gel, is held therein in a state of substantially stable It has beenfound that by the practicing of my inventionthe solid .fuel (e. g., coal) need not be reduced in particlesize to the.

colloid-like state iii-order to effect the production of a stable mobile fuel product therefrom, it. being necessary only that the solid fuel particles be of asuliicient degree- -of fineness so that they readily may pass thr'oughthe passages of the fuel burning apparatus without danger of clogging,i. e., of about the particle size of ab ut from 100 to 200 mesh. The petroleum soluble, non-aqueous, mobile, colloidal gel serving as the suspension agent for the finely divided solid fuel is prepared, as hereinbefore mentioned, by dissolving in a normally liquid petroleum hy drocarbon mixture (e. g, fuel oil) an alkali metal salt of a saponifiable, organic acidic product obtained by the controlled oxidation of a normally liquid aliphatic hydrocarbon or hydrocarbon mixture. The said alkali metal salt does not form with the fuel oil a true's'olution, but forms a mobile colloidal solution, or gel whiohis sufficiently fluid to permit being pumped easily- J There follows a detailed description of the preferred process of making'the petrolcmn soluble, non-aqueous mobile colloidal gel, it being understood that the invention is not limited to the specific materials. proportions and conditions" hereinafter to. be set out, which are understood to be exemplary:

Although the organic acidic products obtained by the controlled liquid-phase oxidation of hydrocarbons or mixtures thereof generally, under such conditions as to obtain water-insoluble, saponifiable, organic acidic. products, are adapted foruse in the preparation of the-aforesaid alkali metal salts, I prefer, forpurely economical reasons, to employ the organic acidic products from the cheapest fuel oil available,-for instance, the fuel oil known as"36 to 40? .Baum fueldistillate. When a:' petroleum 1,684,125 ,QFFHQE,

" carbon mixture.

- ganic compounds, unoxidized petroleum hydrocarbons, and a water-insoluble, saponifiable, organic, acidic product which is wholly or partly soluble in the petroleum hydro- In the oxidation step, the

oxidation per se may be initiated by the presence in the petroleum distillate of a. of an oxidizing catalyst, such small amount as a compound of manganese, copper or iron,

say manganese stearate, amounting toabout 0.1 ercent of the weight of the petroleum distillate. Or, the oxidation may with equal facility be initiated by providing as the charge of raw material to undergo oxidation a mixture comprising about equal parts by weight or volume of fresh petroleum distillate and unoxidized petroleum hydrocarbons from a previously treated charge.

The oxidation step preferably is terminated at a point where incipient formation of oxidation products insoluble in the 'reaction mixture commences; e. g. at a point where the partially oxidized mass contains from about 'to'about percent of saponifiable acidic roducts as titrated for a molecular weig t of 280. acidic products consist essentially of simple aliphatic carboxylic acids derived from the aliphatic hydrocarbons which made up the bulk'of the petroleum distillate starting material. They are insoluble in water but soluble in the petroleum distillate.

For obtaining the desired saponifiable organic acid product, the above-described reaction mixture is washed withwater, thereby removing the water-soluble" acids, and the resulting washed product is treated with an aqueous solution of a caustic alkali in quantity sufiicient to 'saponify the acid compounds constituting the said water-insoluble, saponifiable organic acidic product. The reaction mixture resulting from the treatment with caustic alkali solution is diluted with water,-in order to throw out of solution any dissolved unsaponified material, whereby there are formed, upon standing. a supernatant non-aqueous oilylayer comprising'unoxidized material and unsaponifiable products of oxidation, and a subnatant aque ous layer comprising a solution of the alkali metal salt of the saponifiable organic acidic product. v

The subnatant aqueous layer is carefully separated from the supernatant oily layer of about from These saponifiable i,ea4,iab

and is dehydrated to a The dehydration may danger of charring, by subjecting the aqueperfectly dry mass.

ous solution to evaporation treatlnent at'a.

than from the soap solution alone; also, the

soap solution is less prone to decomposition. To the solution of non-aqueous soap in fue a; 'sufiicient quantity of fuel oil to yield the desired concentration .of soap in the mixture.

The dehydrated mass, resulting from the above described treatment and consisting esscntially of the alkali metal salt of the saponifiable organic acidic product obtained by the controlled oxidation of a normally liquid petroleum hydrocarbon mixture, is found to be soluble in ordinary fuel oil to the production of a colloidal solution. Said colloidal solution-has strong gel-forming tendencies, it being a fact that the presence of only about 1 to 2 parts by weight of said alkali metal salt in parts by weight of the solution effects the production of a colloidal gel which, while sufiiciently fluid to be pumped easily, is capable of holding therein powdered coal having a particle size 100 to 200 mesh in astate of stable suspension for a prolonged period of time, i. e., a month or more. The onversion of the fuel oil from a liquid state to the state of a mobile gel apparently does not detract from its fuel value. 'Powdered coal of about from 100'to 200 mesh is introduced into said fuel "oil gel and suspended therein by simple mechanical agitation.

The relative proportion of powdered coal to fuel oil gel may be varied within wide limits, it being possible to prepare a stable mobile fuel product therefrom containing equal parts by weight of the coal and the gel. It is to be noted that the relative proportions of the coal and the gel may be so selected as to obtain an atomizable mobile fuel product having a predetermined thermal value and density per unit of volume. For example, the powdered coal-and the fuel oil gel may be brought together in" such proportions as to yield a weight between 8 and 12 pounds per gallon (231 cubic inches) of space and having, especially in the more dense compositions, a thermal value much greater thanthat of an equal volume of fuel oil or of powdered coal alone. It is a remarkable fact that, although on long standing there may occur some stratibe effected, without.

product ranging in an oil obtained by the above procedure, I add" 1. Process which comprises producing apetroleum soluble, non-aqueous mobile colloidal gel from amormally liquid petroleum hydrocarbon mixture and suspending in said non-aqueous mobile colloidal gel finely divided solid fuel.

an atomizable 2. Process of producin ving the suspenmobile fuel product invo sion of finely divided solid fuel in a liquid fuel in the resence of a stabilizing agent, characterized in that there is used as the stabilizing agent a petroleum soluble, alkali metal ,salt of a saponifiable organic acidic product substantially identical with that ob tained by contacting an oxidizing gas with a normally liquid petroleum hydrocarbon mixture, in liquid phase, at reacting temperatures and at a pressure greater than atmospheric pressure.

3. Process of producing an atomizable mobile fuel product which comprises dissolving in a normally liquid petroleum hydrocarbon mixture a petroleum soluble, neutral alkali metal salt of a saponifiable organic acidic product substantially identical with that obtained by contacting an oxidizing gas with a normally liquid petroleum hydrocarbon mixture, in liquid phase, at reacting temperature and at a pressure greater than atmospheric, whereby there is obtained a mobile colloidal gel of said normally liquid petroleum hydrocarbon mixture, and suspending in said mobile colloidal gel finely dividedsolid fuel.

4. As a new atomizable mobile fuel product, a substantially stable suspension of finely divided solid fuel in a non-aqueous, mobile, colloidal'gel comprising a normally liquid petroleum hydrocarbon mixture and a petroleum soluble alkali metal salt of a saponifiable organic acidic roduct substan tially 'dent'cal with that o tained by contactmg an oxidizmg gas with a normally etroleum hydrocarbon mixture, in

liquid iase, at reacting temperature and at liquid p a pressure greater than atmospheric pressure.

5. As a new atomizable mobile fuel prodnot, a substantiall stable suspension of finely divided soli fuel in a non-aqueous mobile, colloidal gel comprising a solution containing about 98 parts b weight of a normally li uid petroleum hy rocarbon mixture and a ut 2 parts by weight of a petroleum soluble alkali metal salt of a saponifiable organic acidic roduct substantially identical with that o tained by contac'ting an oxidizing gas with a normallyliquid petroleum hydrocarbon mixture, in liquid phase, at reacting temperature and at a pressure greater than atmospheric pressure.

6. As a new atomizable mobile fuel product, a composition comprising about 100 parts by weight of powdered coal having a particle size of about from 100 to 200 mesh suspended ina fuel oil gel consisting of about 98 parts by weight of a normally liquid fuel oil and about 2 parts by weight of a petroleum soluble alkali metal salt of a saponifiable organic acidic product substantially identical with that obtained by contacting an oxidizing gas with a normally liquid petroleum hydrocarbon mixture, in liquid phase, at reacting temperature and at a pressure greater'than atmospheric pressure. i

7. Process of producing an atomizable mobile fuel solving in a normally liquid petroleum h drocarbon mixture an alkali metal saltof a saponifiableorganic acidic product obtained by the controlled oxidation of normally liquid petroleum hydrocarbons.

8; As a new atomizable mobile fuel product, a substantially stable suspension of finely divided solid fuel in a: non-aqueous, mobile, containing. a normally liquid petroleum hydrocarbon mixture and an alkali metal product which comprises discolloidal gel, comprising a solution obtained by the controlled oxidation of a normally liquid petroleum hydrocarbon mixture.

' In testimony whereof, I afiix my signature ARTHUR W. BURWELL.