28 parts of 1-hydroxyethyl-2-lauryl imidazoline were added to the reaction kettle, then 90 parts of water were added, and 2 parts of NaOH were added under stirring. After stirring evenly, stir and raise the temperature to 80 ℃, and open the ring for 2h. Then slowly add 3-chloro-2-hydroxypropanesulfonate aqueous solution (330 parts of water, 393 parts of 3-chloro-2-hydroxypropanesulfonate). Stir at 75~80 ℃ for 1h, then neutralize with 200kg 40% of NaOH, and stir for 4h. Add 135 kg of triethanolamine and stir at 70~80 ℃ for 3 hours to obtain the product.