GB727155A - Improvements in or relating to stabilized heating oil - Google Patents

Abstract

A petroleum hydrocarbon fuel oil containing at least 10 per cent. by volume of stocks derived from thermal or catalytic cracking operations is stabilized by intimately contacting it with an alkali, alkaline earth or ammonium salt of an acid derived from phosphorus, antimony, arsenic or bismuth, together with a detergent consisting of an oil soluble alkali or alkaline earth sulphonate or a metal soap of a C16-C24 fatty acid or a naphthenic acid. The preferred detergents are the petroleum sulphonates of Na, Ca, Ba, Sr and Mg. The preferred salts are sodium salts of phosphorus acids, especially Na3PO4. Other salts used include Na2HPO4, NaH2PO4, Na4P2O7, Na3PO3, (NH4)2HPO4, and sodium arsenite, arsenate, and bismuthate. They may be anhydrous or hydrated. The amount added is about .0001-.1 weight per cent. of anhydrous salt. The salt may be added as a mixture with the petroleum sulphonate containing about 2-20 per cent. of the salt. About .0005-5 weight per cent. of the mixture is used. A complex may be formed by adding an aqueous solution of the salt, e.g. Na3PO4, to an oil concentrate of the petroleum sulphonate, and heating to 300 DEG F. to dehydrate. The concentrate of the complex may then be used to stabilize fuel oils. Stability tests on a commercial fuel oil consisting of a blend of catalytically cracked, thermally cracked and virgin stock are given, various phosphates in concentrates of a sodium petroleum sulphonate in naphthenic lubricating oil being added. Tests on other salts added as concentrates in lubricating oil containing sodium petroleum sulphonate are also given. Stability may be further increased by adding the complex together with an alkaline earth metal alkyl phenol sulphide, e.g. barium isooctyl phenol sulphide. Examples wherein an addition of the latter equal to .002 and .004 weight per cent. are given. Other additives may be incorporated. Specification 727,153 is referred to.