Preparation method of amino modified layered double hydroxide

The invention relates to a preparation method of amino modified layered double hydroxide, which comprises the following steps: (1) weighing and dissolving 2.0-5.0g of anionic surfactant and 5.0-7.0g of aminosilane in 150mL of alcohol aqueous solution to obtain solution A; preparing 50-100mL of solution B from magnesium nitrate hexahydrate and aluminum nitrate nonahydrate according to a molar ratioof 3.1; (2) dripping the solution B into the solution A at the speed of 0.5-1.0mL/min, starting an ultrasonic cell crusher to carry out ultrasonic treatment on the solution at the same time, whereinthe frequency is 5s, stopping the ultrasonic treatment for 5s, continuously stirring the solution in the dropping process, and keeping the pH value equal to 10+/-0.1; and (3) after the dripping of thesolution B is finished, closing the ultrasonic cell crusher, aging for 4 to 6 hours at the temperature of between 60-80 DEG C, performing suction filtration, washing and drying to obtain the amino modified layered double hydro