Patent ID: 6162770
Filing Date: 2000-12-19
Classification: C07C,C10M,C10N

Abstract:
A method for producing an unsulfurized, alkali metal-free additive for lubricating oils comprising:(a) neutralizing alkylphenols using an alkaline earth base in the presence of at least one carboxylic acid containing from one to four carbon atoms, and in the absence of alkali base, dialcohol, and monoalcohol, to produce an alkylphenate wherein:(1) said neutralizing operation is carried out at a temperature of at least 200.degree. C.;(2) the neutralizing operation is carried out at a pressure that is reduced gradually below atmospheric in order to remove the water of reaction, in the absence of any solvent that may form an azeotrope with water;(3) said alkylphenols contain up to 85% of linear alkylphenol in mixture with at least 15% of branched alkylphenol in which the branched alkyl radical contains at least nine carbon atoms; and(4) the quantities of reagents used correspond to the following molar ratios:(a) alkaline earth base/alkylphenol of 0.2:1 to 0.7:1;(b) carboxylic acid/alkylphenol of from 0.01:1 to 0.5:1;(b) carboxylating the alkylphenate obtained in step (a) using carbon dioxide under carboxylation conditions sufficient to convert at least 20 mole % of the starting alkylphenols to alkylsalicylate; and(c) filtering the product produced in step (b) to remove any sediment.