METHOD OF PREPARING LUBRICANT OIL ADDITIVES Russian patent published in 2010 - IPC C10M159/22 

FIELD: chemistry.

SUBSTANCE: at the first step (C₈-C₁₈)-alkylphenol, elementary sulphur and calcium oxide or hydroxide react in the presence of ethylene glycol in molar ratio of calcium oxide or hydroxide : ethylene glycol equal to 1:0.2-0.5. At the second step the obtained product reacts with an additional amount of calcium oxide or hydroxide and ethylene glycol in the presence of modifying additives in molar ratio equal to 1:0.2-0.6, and then treated with carbon dioxide at flow rate of carbon dioxide equal to 0.02-0.04 mol/min·mol of alkylphenol. The modifying additives are selected from: oil-soluble sulfonic acids, sulfonates, higher fatty acids, alkenyl succinic acid (C₁₈-C₅₀), succinimide or mixtures thereof. The modifying additives are preferably used in amount of 3-45 wt % per alkylphenol.

EFFECT: higher colloidal stability of additives with high alkalinity, improved anti-oxidation and anti-soot properties.

2 cl, 1 tbl, 12 ex