Method for preparing magnetic active carbon composite material for water processing

The invention provides a method for preparing a magnetic active carbon composite material for water treatment in the technical field of environmental purification. The method comprises the following steps: mixing active carbon and corresponding metal salt solution, and generating magnetic nano granules in pore canals of the active carbon in situ by using the characteristics of instantaneous high temperature, high pressure, high cooling speed and the like generated by ultrasonic waves; and filtering and drying the obtained compound, and treating the compound at high temperature to form the magnetic active carbon composite material, wherein the magnetic material accounts for 15 to 50 percent in the whole material in terms of weight percentage, and the active carbon material accounts for 85 to 50 percent. The invention provides a new method for generating magnetic nano particles in the pore canals of the active carbon; and the prepared magnetic active carbon keeps larger specific surface area, reserves the open pore canals from the active carbon, removes organic substances and inorganic heavy metal ions in water treatment, and is easy for magnetic separation and convenient to recover.