Sodium petroleum sulfonate collector for fluorite flotation and its preparation and application method

A sodium petroleum sulfonate collector for fluorite flotation, comprising sodium petroleum sulfonate and non-polar oil, wherein the molar ratio of the non-polar oil to the sodium petroleum sulfonate is 3.33-5.67, the sodium petroleum sulfonate comprises raw material oil and active substance, the molecular weight of the raw material oil is 350-450, the content of the active substance is 35%-60%, the molecular weight of the sodium petroleum sulfonate is 500-750, the raw material oil comprises aromatic hydrocarbon, and the content of the aromatic hydrocarbon is between 10% and 31%, the aromatic hydrocarbon comprises benzene ring hydrocarbon and naphthalene ring hydrocarbon, the content of the benzene ring hydrocarbon is between 5% and 11%, and the content of the naphthalene ring hydrocarbon is between 5% and 5.2%, the raw material oil needs to be sulfonated by sulfur trioxide, and the molar ratio of the aromatic hydrocarbon to the sulfur trioxide in the raw material oil is between 2.4 and 5.