PFOS-free seawater-resistant low-temperature-resistant aqueous film-forming foam extinguishing agent

The invention discloses a PFOS-free seawater-resistant low-temperature-resistant aqueous film-forming foam extinguishing agent which comprises the following components in percentage by mass: 1%-10% of a first-group surfactant, 6%-18% of a second-group surfactant, 10%-40% of an anti-freezing agent, 0.1%-1% of a thickening agent, 2%-5% of an anti-burning agent, 1%-3% of a cosolvent, 0.1%-1% of a preservative, 0.01%-0.1% of a pH regulator and the balance of water. The aqueous film-forming foam extinguishing agent is prepared by the following steps: adding the thickening agent into water to form a component A; weighing a first group of surfactants, adding the first group of surfactants into water, then weighing a second group of surfactants, and adding the second group of surfactants into water to form a component B; weighing an antifreeze agent and a cosolvent to form a component C; mixing A, B and C to form a component D; adding an anti-burning agent, a preservative and a pH regulator into D; and adding the bal