METHOD OF PRODUCING DIALKYLDITHIOPHOSPHATE ADDITIVES Russian patent published in 2025 - IPC C10M137/10 C10M129/00 C10M129/28 C10M125/10 C10M159/20 

FIELD: oil industry.

SUBSTANCE: invention relates to oil refining and petrochemistry, specifically to a method of producing a multifunctional zinc dialkyldithiophosphate additive for use in lubricating oils. Method of producing dialkyldithiophosphate additives involves reacting alkylphenols or C₃-C₈ alcohols with pentasulphurous phosphorus, neutralizing the obtained alkylphenyl- or dialkyldithiophosphoric acids with APDTPA or DADTPA with zinc oxide and subsequent separation of unreacted zinc oxide by filtration or centrifugation. APDTPA or DADTPA is neutralized at temperature of 70-90 °C by feeding 20% of excess zinc oxide per weight of mixture of alkylphenyl- or dialkyldithiophosphoric acids, wherein a diluent-stabilizer is added to the reaction mass in amount of 10 to 50% of the weight of the neutralized acid, and the diluent-stabilizer used is a mixture of esters of terephthalic acid with paraffin-naphthenic oil in a weight ratio of 1:9 to 7:3.

EFFECT: development of a method for obtaining an additive to lubricating oils with improved technological and operational characteristics both during transportation and storage, and as part of commercial oils, reduced time for synthesis of the additive, as well as improved effect of the additive on thermal-oxidative stability and antifriction properties of commercial oils.

1 cl, 6 tbl, 14 ex