US1791521A - Process of refining oil - Google Patents

Description

atented Feb. 10, 1931 PATENT! OFFICE AUGUST P. BJ'ERREGAARD, OF OKMULGEE, OKLAHOMA PROCESS OF REFINING- OIL No Drawing.

One of the present day standard requirements in the gasoline trade is that gasoline offered for sale shall be non-reactive or sweet to the-sodium plumbite or doctor test. As is well known, moreover, gasoline from the still is refined usually by treatment first with sulfuric acid and then either by treatment with litharge and sodium hydroxide or with sodium hypochlerite, the

treatment with litharge and sodium hydroxide or with hypochlorite being necessary to render the gasoline sweet to the doctor test.

It is the custom at present, moreover, at manyretail gasoline or filling stations to exhibit to the customer the product being sold by using filling bowls of glass. Ithas developed that many gasolines refined so as to pass the doctor and other ordinary trade tests are light sensitive, causing the gasoline toturn darker in the glass filling bowls on standing therein and also depositing a film of dark gum that collects on the glass, thus doubly darkening the tint of the gasoline as viewed by the purchaser. According to the present invention, straight-run and cracked gasoline or mixtures of straight-run and cracked gasolines are refined to produce a gasoline which is sweet to the doctor test, non-corrosive, of good odor'and light stable. The term light stable as just used is intended to include both the characteristics of not substantially darkening and of not depositing gum upon exposure to light.

When gasoline is refined according to the present invention, most of the previously known chemicals for treating processes are not required. In fact, some of them are detrimental if combined with the present process. In refining gasoline according to the present invention, a little normal or primary alcohol is added to the sour gasoline preferably in the raw or untreated state, whichis then treated with a hydroxide of alkali metal or of alkali earth of heavier atomic weight than calcium until sweet to the doctor test. The gasoline will then be found to be light stable and of good odor requiring no further treatment.

Application filed August 26, 1925. Serial No. 52,683.

The primary alcohols used according to the whereas normal propyl, normal butyl and higher normal or primary alcohols act more slowly and still more slowly. A methyl alcohol suitable for use in the present process is pure wood alcohol, approximately test, and substantially free from acetone. I have been successful in rendering gasolines, both sweet to the doctor test and light stable when using as little as of 1% by volume of methyl alcohol to gasoline treated. The amount of alcohol necessary when using a given primary alcohol and a given gaso-. line can be readily determined by a routine test prior to commercial operation, The presence of acetone in the alcohol used according to the present process does not prevent the resulting gasoline from being sweet, but it is not completely light stable. It is, however, improved as to its characteristics toward light in that While it goes off color slowly it does so without production of cloud or gum. Acetone by itself without alcohol is not efiective in making gasoline either sweet to the doctor test or completely light stable.

None of the secondary alcohols, if used instead of methyl or other primar alcohol in the present process, makes t e gasoline finally and fully sweet to the doctor test, even after twenty-four hours action. They, however, favorably affect the gasoline as to its reaction when exposed to light, the color of the gasoline after light exposure being less intense if it has been first treated with secondary alcohol and caustic soda or equivalent hydroxide. The secondary alcohols, however, develop a strong yellow tone in the gasoline if attempted to be used according to the present invention.

The alkaline material or hydroxide used along with or subsequent to the treatment of the gasoline with normal alcohol according to the present invention may be either putas sium, sodium, lithium, barium or strontium hydroxide. However, lithium, barium and strontium hydroxides must remain in contact with the alcohol treated gasoline a longer time than potassium or sodium hydroxide to make it sweet. Commercially, caustic soda is the most available alkaline substance for use according to the present invention. It may be added to the gasoline preferably in a powdered state after or along with the treatment with the alcohol with agitation of the caustic and gasoline till sweet to the doctor test. The preferable method, however, is to percolate the alcohol treated gasoline through a mass of granulated caustic soda until sweet to the doctor test. A sirupy solution of caustic soda or caustic potash in pure methyl alcohol may be used instead of treatment first with the alcohol and then with the hydroxide, but a dilute solution is not operative. As little as 0.2 lb. of powdered caustic soda per barrel of gasoline is often effective in producing a sweet li ht stable gasoline according to the present invention. The amount of caustic or other hydroxide required in treating gasoline according to the present invention varies with the gasoline and the hydroxide and may be determined readily for any given gasoline and a given hydroxide by a routine test preliminary to commercial operation.

The use of normal alcohol alone without subsequent treatment with hydroxide does not produce the desired result. The same is true of treatment with caustic alone without treatment with normal alcohol.

The gasoline to be treated by the present process must be substantially free from water throughout the process in order to obtain the desired results. Moreover, the gasoline used must be unsweetened. If the gasoline has been sweetened by either the sodium plumbite or sodium hypochlorite treatment, subsequent treatment according to the present invention is not efi'ective in producing a light stable gasoline.

Acid treatment with 66 Beaum sulfuric acid may be applied before the treatment according to the present process without detriment but it is not necessary. Acid treatment with Beaum sulfuric acid however is detrimental either before or after treatment of the gasoline according to the present process, and especially detrimental after it..

The process of refining gasoline according to the present invention is applicable to gasolines direct from the still without any redistillation. In fact, the major portion of the experimental work done on the present invention has been on a blerd of distillates direct from the pressure still and direct from the crude still.

Gasoline treated by the process of the present invention is of greatly improved odor and needs no further treatment to improve its odor for sale. As to color, the rocess of the present invention does not c ange the original color of the gasoline.

It will be understood that wherever the phase caustic alkali hydroxide or alkali hydroxide is used in the following claims, hydroxides of the heavy earth metals, barium and strontium, are intended to be included.

It will be understood further that the alcohol referred to in the claims as high-test alcohol may contain some acetone. The acetone is effective along with the alcohol in preventing gum formation as described above and comes within the contemplated scope of the present invention.

Having thus described my invention, I claim:

1. A process of treating gasoline comprising removing water from the gasoline, mixing with the dry gasoline a high test alcohol, mixing the alcohol-gasoline mixture with a dry caustic alkali hydroxide, and separating the alcohol-gasoline mixture from the alkali hydroxide.

2. A process of treating gasoline comprising mixing less than one per cent of substantially dry methyl alcohol with the gasoline, treatin the mixture with a caustic alkali hydroxide, and separating the mixture from the alkali hydroxide.

3. A process of treating gasoline comprising mixing a small amount of the methyl alco 01 with the gasoline and passing the gasoline-alcohol mixture through a bed of powdered caustic hydroxide.

4. A process of treating asoline comprising removing water from t e gasoline, mixing substantially pure methyl alcohol with the dry gasoline, and passing the gasolinealcohol mixture through a bed of powdered sodium hydroxide. D

5. A process for refining gasoline comprising mixing a dry normal alcohol with substantially dry raw gasoline, contacting the resulting alcohol-gasoline mixture with adry powdered alkali hydroxide, and separating the alcohol-gasoline mixture from the alkali hydroxide.

t). The process of treating gasoline comprising forming a mixture of substantially dry gasoline with less than 1% of its volume of substantially dr alcohol, contacting the mixture with dry a ali hydroxide, and separatin the mixture from the alkali hydroxide.

7. The process of treating gasoline to render it light stable, which comprises formin a solution of dry unsweetened gasoline wit% a relatively small proportion of dry primary alcohol, contacting the resulting gasolinealcohol solution with an alkali hydroxide, and separating the gasoline-alcohol solution from the alkali hydroxide.

8 The process of treating sour gasolines, which comprises forming a mixture of substantially dry gasoline with a relatively small 1,701,5si r I roportion of substantial dry primary alcool, contacting the resulting mixture with a substantially dry alkali hydroxide, and separating the said mixture from the alkali hydroxide.

9. The process of treating sour gasolines, which comprises contacting the gasoline with concentrated sulphuric acid, thereafter forming a mixture of the gasoline with a small proportion of substantially dry primary alcohol, contacting the resulting mixture with a sub stantially dry alkali hydroxide, and se arating the said mixture from the alkali ydroxlde.

In testimony whereof I aflix my signature.

AUGUST P. BJERREG-AARD.