Oily tubular membrane and preparation method thereof

The oily tubular membrane comprises a composite membrane of a tubular structure, the composite membrane sequentially comprises a supporting layer, a base membrane layer and a protective layer from outside to inside, the supporting layer is a non-woven fabric layer or a PET layer, the base membrane layer is a modified polyethersulfone ultrafiltration membrane layer, and the protective layer is a non-woven fabric layer or a PET layer. The liquid membrane preparation liquid of the modified polyether sulfone ultrafiltration membrane layer is mainly prepared by reacting the following materials in percentage by weight in a reaction kettle: 10 wt%-30 wt% of polyether sulfone, 0.1 wt%-10 wt% of lipophilic nano silicon dioxide, 50 wt%-80 wt% of dimethylacetamide, 1 wt%-10 wt% of methacrylic acid, 0.5 wt%-10 wt% of acrylonitrile, 0.5 wt%-10 wt% of azodiisobutyronitrile and 0.5 wt%-10 wt% of polyethylene glycol, and the protective layer is white oil. The invention further discloses a preparation method of the oily tubul