Modified preparation method for nano nickel ferrite micro-particle capable of dispensing in alkyl benzene refrigerator oil, alkyl benzene refrigerator oil thereof and preparation method for the alkyl

The invention provides a method for preparing and modifying nano nickel ferrite particles dispersing in alkyl benzene freezing oil, and alkyl benzene freezing oil containing nano nickel ferrite particles according the method, wherei, the method is characterized in that firstly dodecylbenzene sulfonate is added in preparation process of nano nickel ferrite particles or added into prepared nano nickel ferrite particles to grind and bake, then alkyl benzene refrigerator oil saturated by surfactant MH-95 is added with ground surfactants, such as sorbitan monooleate, potassium alkyl phosphate and span-80 for ultrasonic dispersion. The prepared nickel ferrite nanoalkyl benzene freezing oil sol has better friction resistance than conventional alkyl benzene freezing oil, and has moderate intersolubility with hydrofluorocarbon and carbon dioxide refrigerant, which can be used for refrigerator oil of refrigeration compressor using HCFCs, HFCs and CO2 as refrigerant.