EMULSIFIER FOR INVERT EMULSIONS AND PREPARATION METHOD THEREOF Russian patent published in 2019 - IPC B01F17/08 C09K8/00 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to emulsifiers of invert emulsions and can be used in producing homogeneous mixtures of immiscible liquids, which are two-phase systems used in oil and gas industry, including drilling and killing wells, as well as increasing oil recovery by waterflooding. Emulsifier of invert emulsions contains an oil-soluble surfactant in form of a mixture of esters of oleic, linoleic, linolenic, as well as resin acids and triethanolamine, a water-oil-soluble surfactant and a hydrocarbon solvent, with the following ratio of components, wt%: oil-soluble surfactant 18÷50, water-oil-soluble surfactant 2÷20, hydrocarbon solvent – balance. Water-oil-soluble surfactant is obtained by sulphonation of fat with a sulphonating agent with subsequent neutralization of the reaction mass to pH 6–7 with an alkaline agent and separation of the formed aqueous phase, where the fat is represented by technical fish fats – fish processing industry wastes, and the sulphonating agent used is a mixture of mineral oil, non-ionic surfactants and oleum, wherein mineral oil is represented by industrial oil I-L-A-10 or I-LH-A-15, as non-ionic surfactants – Neonol AF_9-6 or Neonol AF_9-12 in an oil:surfactant:oleum ratio of 0.5:0.5:1.0 by weight. Sulphonation is carried out in a reactor with constant stirring and temperature of 50–110 °C for 1.5–30 minutes at a weight ratio of cod-liver oil to sulphonating agent equal to 1.0:(0.1÷0.3), alkaline agent used is 5–10 % aqueous solution of sodium hydroxide or triethanolamine. Hydrocarbon solvent used is arctic diesel fuel or jet fuel JP-1, or transformer oil VG. Emulsifier preparation involves introduction of a hydrocarbon solvent into the mixture of surfactants and mixing until a homogeneous product forms.

EFFECT: providing stable back emulsions which do not decompose at temperature of 90 °C for 24 hours and at temperature 20 °C for 8 hours, possibility of formation of direct emulsion solutions and efficiency in case of application for increasing oil recovery of the formation.

1 cl, 2 tbl, 3 ex