Method of dissolving or dispersing metal naphthenates in liquid hydrocarbons, especially lubricating oils

摘要

Metal naphthenates are dissolved or dispersed in liquid hydrocarbons such as lubricating oils to produce liquid compositions, with the aid of an auxiliary solvent A which has the formula XO(RO)nROY wherein R is C2H4 or C3H6, n is 2 or a larger integer, X is a hydrocarbon or acyl radicle containing more than 6 carbon atoms and Y is hydrogen or a hydrocarbon or acyl radicle. If desired, a second auxiliary solvent B may also be employed which is an ether which contains a radicle having more than 6 carbon atoms and which is free of polyglycol groups. Specified metal naphthenates are the naphthenates of potassium, calcium, barium, zinc, aluminium, iron and lead, while liquid hydrocarbons mentioned are tetrahydronaphthalene, and various mineral oil fractions such as diesel oil, spindle oil, engine lubricating oil and upper cylinder lubricating oil. Lists of polyglycol ethers, esters and ether-esters suitable as auxiliary solvent A, and also of aliphatic, aromatic, alicyclic or mixed ethers suitable as auxiliary solvent B, are given. The liquid hydrocarbon compositions may contain additional ingredients such as pour point improvers, viscosity improvers and antioxidants. Suitable antioxidants are phenols (e.g. p-ethylhexylphenol and di-tert.-butyl-p-cresol), secondary aromatic amines, phenthiazine, esters of phosphoric or thiophosphoric acid and salts of thiophenols. Fourteen examples of the preparation of liquid hydrocarbon compositions according too the invention are given.