US2421421A - Process of treating high-molecularweight hydrocarbons - Google Patents

Description

meme June 3, 1947 PROCESS OF TREATING HIGH-MOLECULAR- WEIGHT HYDROOARBONS Arnold J. Hoiberg, El Dorado, Aria. assignor to Lion Oil Company,

ware

corporation of Dela- No Drawing. Application May 26, 1944 Serial No. 531,539

This invention relates to a process of treating high-molecular-weight hydrocarbons and bitu-- minous materials and more particularly'to a method for blowing asphalts and other bituminous materials.

Among the objects of this invention are the provision of an improved method for blowing high-boiling hydrocarbon materials with an oxygen-containing gas at elevated temperatures particularly such materials as asphalt and high molecular petroleum hydrocarbons containing only portions of hydrocarbon waxes to produce an asphaltic product; the provision of a method of the type indicated which permits decreasing the blowing time; the provision of a method of the type indicated which permits obtaining higher penetrations for a given softening point blownasphalt, and the provision of a method 'of the type indicated which utilizes only relatively minor proportions of catalytic materials as aids to the blowing operation. Other objects will be in part apparent and in part pointed out hereinafter.

The invention accordingly comprises the steps and sequence of steps, and features of manipulation, which will be exemplified in the methods hereinafter described, and the scope of the application will be indicated in the following claims.

.7 Claims. (01. 196-74) wide limits or both such reduction and variation. Among the catalysts which are useful for this purpose are the chlorides of certain metals such as zinc, iron, copper and antimony. These increase the penetration and reduce the time of blowing where a given softening point is obtained'. In the examples of this specification the term flux is intended to mean oxidizable residuum from distillation of crude petroleum.

It has now been found that the activity of halide salt catalysts may be enhanced by the addition of a small proportion ofwertain metallic powders. The metal powder employed is pref- In the usual process 'of air-blowing hydrocar bon materials including mineral lubricating oils and asphalt, the air or other oxygen-containing gas used as a blowing fluid is contacted with the hydrocarbon material which has been heated to a temperature usually between 400 to 550 F. Depending only slightly upon the temperature, type of blowing still and rate of air input; a given penetration or consistency is invariably obtained when a given asphaltic or hydrocarbon material is oxidized to a specified softening or end point. Also, with the same equipment, temperature and rate of air input, the time required for oxidation of a given oxidizable hydrocarbon to a specified softening or end point is invariably substantially the same.

It has previously been found, however, that the introduction of a small amount of a catalyst into the material to be an asphalt, a pitch or a mineral lubricating oil, will reduce the time required for oxidation or permit varying the consistency of the blown product at a given end point within relatively treated, such as a flux,

erably in a very fine state of subdivision. Larger size particles are effective, but the ,femciency is substantially lower than smaller particles and a higher concentration is required. The smaller the size of the metal particles the more active they are as promoters.

It has also been found that certain catalysts to this process are sufliciently volatile that they can be eliminated to an appreciable extent from the material in process, during the blowing thereof because of the temperature employed during blowing. Such catalysts includealuminum chloride, zinc ammonium chloride, mixtures of zinc chloride and ammonium chloride and boron fluride. These are preferably used in conjunction with finely divided metal promoters.

Some of the results of experimental studies are shown in the following tables although no attempt is made to show therein the benefits derived from employing extremely finely divided catalyst and promoters.

In these tables the percent reduction in time is in accordance with the following formula:

' Tn-Tc v 100 Tn and the percent increase in penetration is computed as follows:

Pc-Pn 100 Pn In the above formulas Tn is normal or noncatalytic time and To is catalytic time; Pn is normal or non-catalytic penetration and Fe is catalytic penetration. The flux used in Table 1 below was a Shuler flux of seconds Saybolt furol viscosity at 210 F. which was blown to 200 to 210 F. melting point by ring and ball method.

Table 1 Per Cent Concentration and Qatalyst Beduction gg g z Per Cent by Weight in gigging Penetration 0.75 A1011 17 20 0.50 A1+0.60 A1011. 21 52 0.25 Mg+0.75 A101; 47 27 0.20 C11+0.75 AlCh. 37 22 0.25 Z11+0.25 A101]- 49 33 0.50 Ell-H115 A1 3- 33 14 0.50 MEG]: 27 0.23 Fe+0.46 MgCh--- 46 19 0.25 Zn+0.75 MEG/11-- 39 4 0.50 Z1161: 11 24 0.25 F6+0.50 Z1101]..- 33 14 0.50 MgClzbHr 16 3 0.25 Sb+0.50 MgCh 61120 15 12 0.25 M0 0.50 Mg 22 12 0.25 Mil-F050 MgC12.6HzO 15 12 0.50 C 13 30 0.25 F6+0.25 CHI 24 33 0.50 A1 3 0.25 Gil-H150 AlFl. 25 0.50 ZDBH 15 19 0.25 Fed-0.50 Z1131: 18 19 In Table 2 below an Urbana flux of 173 float at 122 F. was blown to 200 to 210 F. melting point.

It has also been found that halides of the alkali metals and ammonium also enhance the activity of other halide salt catalysts. .In Table 3 below a Shuler flux of 80 seconds Saybolt furol viscosity at 210 F. was blown to 200 to 210 F. melt.

Table 3 Per Cent Per Cent Concentration and Catalyst Reduction Increase in Per Cent y Weight in Blowing Penetration Tune Other metals may be combined with various halide salts in order to provide an improved blowing process. The time of blowing is decreased or the penetration at a given softening point is increased or both, over the process in which only the halide salt is used. The metals seem to act as promoters and to enhance the catalytic activity of the halide salt.

Similarly the halides of the alkali metals and of ammonium act as promoters and enhance the catalytic activity of other halide salts.

The proportions of the metal powders, or of the halides of an alkali metal or ammonium to be used with the halide-salt primary-catalysts may be varied substantially. The minimum proportion however, should not be substantially less than one part of metal powder or of alkali metal chloride or ammonium chloride to five parts of primary catalyst. Increased proportions of the metal powder, or other promoter within the range for the weight of the entire catalyst set forth below, may be employed without deleterious effect. The total weight of the catalyst may vary from 0.1 percent to 5 percent of the asphalt. Below 0.1 percent the catalytic effect is very small and proportions above 5 percent not only increase the cost too much but seriously contaminate the asphalt or other blown product. 4

Where a volatile halide salt catalyst and/or promoter are employed, a controlled removal of a. very large proportion of these materials during the course of the blowing operation may be carried out. In this way the final blown asphalt need contain only a small proportion of the added nonmetallic compounds. Its ash content will then be low and its water and acid resistance not much reduced by the presence of a water soluble compound.

The above described combinations of catalysts and promoters are also useful in decreasing the time required to convert lubricating oil distillates and fractions derived therefrom to a semi-solid plastic consistency. Also a more fluid product at a given softening point is obtained than by oxidation without the disclosed catalysts. Such plastic products may be used in preparing lubricating compounds; see Patents 1,238,101 and 2,057,473.

Before defining the claims of this invention a few particular examples of blowing procedure and products obtained are presented for the pu pose of further-clarification, as follows:

An asphalt reduced from Smackover crude oil initially having a penetration at 77 F. of 97 was heated in a confining chamber to 490 to 510" F. and then subjected to the action of oxygen by passing a stream of air through it. At the end of 5.25 hours the softening point of the resulting product was found to be 202 F. by the ring and ball method and the penetration at 77 F. by the A. S. T. M. method was found to be 14. The same test was repeated with a fresh sample of the same base asphalt but with the addition of 0.75 percent of FeCls-l-SHzO and 0.25 percent of powdered iron after the asphalt had been prepared for air blowing. It was then air blown while at a temperature within the range 490 F. to 510 F. as before and it was found that the same melting point product was obtained in 1.75 hours of blowing and its penetration was 17. Although air was used as a blowing medium in this'example, other inert aeriform fluids containing free oxygen can be used effectively.

A lubricating distillate from Smackover crude oil which distillate had a viscosity, Saybolt Universal at 210 F. of 68.5 seconds was air blown at .a temperature of 425 F. for 10 hours at the 'end of which time the product was viscous and ceptibility sometimes called a low temperature susceptibility; it was not possible inreasonable time to produce this product without the catalyst and promoter.

It should be noted that although air-blowing hydrocarbons of the class referred to herein is commonly designated as oxidation, it is understood that the efiect on the hydrocarbons blown may be dehydrogenation, polymerization, oxidation or combinations of these effects.

Aluminum, as shown in Table 1, has the effect of changing the penetration more than it influences the duration of the blowing period, whereas magnesium has the reverse effect. Thus it is possible by employing a plurality of finely divided metal promoters and selected catalyst or catalysts to produce various efiects not hitherto obtained. so far as I am aware.

In the foregoing petroleum hydrocarbons such as lubricating oil and asphalt have been referred to as the major materials to be blown but beneficial results are also obtained by similarly blowing other substances particularly bituminous substances.

One effective way of adding the catalyst to the high-molecular-weight material to be blown is to introduce it into said material in the form of a sludge such as would result from first treating a mineral lubricating oil with the catalyst and removing i'rom the mixture the clear treated lubricating oil. However, catalyst may be added .in the relatively pure form alone or in admixture with the powdered metal promoter or in any suitable manner.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in the above methods without departing from the scope of the invention, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

In the practice of this invention it has been found that the eflect of the finely divided metal used in conjunction with a halide salt catalyst is far greater, in the oxidation 01' hydrocarbons of the type mentioned above, than would be expected from disclosures made heretofore, so far as I am aware, relating to the properties of finely divided metals. Although the term promoter" is used herein with reference to the action of said finely divided metals the actual eflect apparently includes catalytic action.

Having described my invention so that one skilled in the art can practice it, I claim:

1. The method of treating a hydrocarbon oi high-molecular-weight to produce an asphaltic product which comprises, blowing said hydrocarbon, in the presence of added portions of a metal halide salt and a finely divided metal, with a gaseous stream containing tree oxygen while said hydrocarbon is at an elevated temperature of the order oi. 400 to 550 F.

2. The method of treating a high-molecularweight petroleum hydrocarbon containing only a minor portion of hydrocarbon wax to produce an asphaltic product which comprises, blowing said hydrocarbon, in the presence of added relatively small portions of a metal halide salt and a finely divided metal, with a gaseous stream containing free oxygen while said hydrocarbon is at an elevated temperature 01' the order of 400 to 550 F.

3. The process of treating a high-molecularweight petroleum hydrocarbon containing only a minor portion of hydrocarbon wax to produce an 'asphaltic product which comprises, mixing with said hydrocarbon added relatively small portions of a metal halide salt and a finely divided metal and blowing the mixture at an elevated temperature with a gaseous fluid containing tree oxygen, thereby forming with the aid of the catalyst and substantially without cracking said hydrocarbon, an improved blown product.

4. The method 01' treating a. high-molecularweight petroleum hydrocarbon of the class lubrieating oil distillates, asphalt, and mixtures of lubricating oil distillates and asphalt to produce an asphaltic product, which comprises, blowing said hydrocarbon while it is at a temperature of the order of 400 to 550 F. with air while it is in the presence of added relatively small portions of an inorganic chloride salt of a metal and a finely-divided metal; said salt and said metal having the property of favorably influencing the comprising an inorganic halide salt of a metal, a

and a promoter comprising a finely divided metal powder.

6. The process of treating a high-molecularweight petroleum hydrocarbon containing only a minor portion of hydrocarbon wax to produce an asphaltic product which comprises, mixing with said hydrocarbon while it is at a temperature of the order of 400 to 550 F. relatively small amounts of a volatile inorganic metal halide catalyst and a finely divided metal promoter, and blowing it with air.

7. A process of treating a high-molecularweight petroleum hydrocarbon of the class lubricating oil distillates, asphalt, and mixtures of lubricating oil distillates and asphalt to produce an asphaltic product, which comprises heating said hydrocarbon to a temperature of the order of 400 to 550 F., introducing into the heated hydrocarbon a relatively small amount of aluminum chloride as a catalyst and a small amount of a finely sub-divided metal and blowing the hot mixture with an aeritorm fluid containing free oxygen; the metal powder having the property of promoting the air-blowing reactions catalyzed by aluminum chloride.

ARNOLD J. HOIBERG.

REFERENCES CITED The following reierencesare oi record in the file of this patent:

UNITED STATES PATENTS Carr et al. II May 16, 1939