US1959315A - Distillate petroleum product and method of treating the same - Google Patents

Description

Patented May 15, 1934 UNITED STATES PAT DISTILLATE, PETROLEUM PRODUCT AND METHOD or TREATING THE SAME James B. Rather and Leslie 0. Beard, Jr., Brook.- lyn, and Orland M. Reiff, Jackson Heights, N. Y., .assignors to Socony-Vacuum Corporation, New York, N. Y., a corporatibn of New York No Drawing. Original application June 25, 1930, Serial No. 463,824. Divided and this application June 7, 1933, Serial No. 674,772

f3 Claims. (Cl. HP-9) This invention relates to distillate petroleum products, more particularlygasoline and kerosene, and .to a method of and means for imparting a stability thereto with respect" to color, gum formation and odor, and for removing any 0b-' je'ctionable color, developed therein during storage.

This application is a division of our application Serial No. 463,824, which in turn is a continuation-in-part of our co-pendingapplications Serial No. 395,192, filed September 25, 1929, and Serial No. 165,546, filed February 3, 1927.

Heretofore we have discovered that certain organic compounds of the nature of negative oxidation catalysts have the property of preventing or materially delaying the formation of color, gum and malodorous constituents in distillate petroleum products, particularly gasoline and kerosene. Notable amongst these compounds are the hydroxybenzenes, especially hydroquinone and pyrogallol. Certain of these compounds, particularly hydroquinone and pyrogallol, have the added property of decolorizing distillate petrowleum products which have becomediscolored during storage.

We have found, however, that a number ofthese compoundswill not function properly in the presence of water, due to the fact that they r are considerably more soluble in water than in the distillate petroleum products. This charof these compounds as stabilizers and decolorizers, particularly when the treated distillates are handled in bulk, because of the difiiculties involved in maintaining tankers, storage tanks, pipe lines and delivery trucks free of water.

In accordance with the present invention, however, the decolorization and/0r stabilization of distillate petroleum products with regard to color, gumformation and odor may be readily and effectually attained regardless of the presence of water, by the use of certain compounds, more soluble in the distillates and less soluble in water,than those previously used.

One of the objects of the present invention is to provide a method of and means for effectually decolorizing and/or stabilizing distillate petroleum products, particularly those of A. P. I. gravity higher than 37 degrees, with respect to color, gum formation and odor in the presence of water.

Another object of the invention is to provide agents or compounds effective in removing initial or recurrent discoloration of distillate petroleum products and for stabilizing the same as to color, odor and the formation of gum, which agents or thoroughly mixed with the distillate to be treated,

resulting solution is then added to the distillate acteristic materially affects the commercial valuecompounds are more soluble in the distillates and less soluble in water than those previously used.

Among the compounds in the nature of negative oxidation catalysts that we have discovered are efiectiveas decolorizers and stabilizers of dis tillate petroleum products with respect to color, gum formation and odor, whether in the presence of water or not, are the alkyl substituted hydroxybenzenes, especially methyl, ethyl, propyl' and butyl pyrogallol. These compounds are formed preferably by substituting alkyl groups for some of the hydrogens in pyrogallol, and are substantially insoluble in water but readily soluble in distillate petroleum products. For example, butyl pyrogallol is only thirty times more soluble in water than in kerosene, whereas pyrogallol is thirty thousand times more soluble in water than in kerosene.

A relatively minute amount, preferably less than 0.01% of the agent'or compound may be although it will be understood that the distillate 'may be percolated through a mass of the compound, if desired. Preferably, however, the compound is first dissolved in a. suitable solvent which is miscible with the distillate, such as an allphatic alcohol, particularly isopropyl alcohol, in the proportion of one p'artof the compound to approximately ten parts of the solvent. The

such an extent that thedistillate contains less than 0.01% of the compound. This method usually results in the compound being distributed throughout and dissolved in the distillate more readily than if it were added directly thereto.

The results of the following tests will illustrate the effectiveness of the treatment of distillate petroleum products in accordance with our invention.

95 A sample of kerosene which had developed a color of minds 15, as measured by the Saybolt chromometer, was treated with one part of propyl pyrogallol to 25,000 partsof oil. After standing for one day the color of the treated oil improved to plus 10, an improvement of 25 points in color. I

Samples of gasoline were treated with equal molecular proportions .of pyrogallol and butyl pyrogallol (one part of pyrogallol to 72,600 parts of oil and one part of butyl pyrogallol to 50,000 parts of oil) The gasolines so treated were stored for six months, and the color by the Saybolt. chromometer and the gum content, by evaporation of 100 cubic centimeters in a porcelain dish were then determined. The results of these tests were as follows:

These results show that when pyrogallol and butyl pyrogallol are used in equal molecular quantities, the butyl pyrogallol isthe more effective stabilizer and decolorizer, because of its greater solubility in the distillate.

While we have thus specifically described our invention, various modifications thereof may suggest themselves to those skilled in the art, and it therefore is our intention that the invention be limited only by the scope of the appended claims. 1

We claim: 7 7

1. A low boiling normally light colored distillate petroleum product of the class of gasoline or kerosene which normally tendsto deteriorate by oxidation, as evidenced by the formation of color or gum therein during storage, having add ed thereto a small amount of a butyl substituted pyrogallol 'sufllcient substantially to retard the aforesaid deterioration, the butyl group being substituted for hydrogen of the benzene nucleus.

2. The method of stabilizing the characteristics of a low boiling normally light colored petroleum distillate product of the class of gasoline or kerosene that normally tends to deteriorate by oxidation, as evidenced by the-formation of color or gum therein during storage, which comprises adding thereto, prior to substantial deterioration as aforesaid, a small proportion of a butyl substituted pyrogallol sufiicient substantially to retard the aforesaid deterioration, the butyl group being substituted for hydrogen of the benzene nucleus.

3; The method of decolorizing a normally light colored low boiling petroleum distillate product of the class of gasoline or kerosene which has become discolored by spontaneous color formation during storage, which comprises adding to said discolored product a small proportion of a butyl substituted pyrogallol sufficient to effect