The invention discloses a preparation method and application of
nitrogen-rich
biochar, and relates to the technical field of
water treatment. The invention aims to solve the problem that
antibiotics and
heavy metals are difficult to remove at the same time in the existing
nitrogen-doped
biochar. The method comprises the following steps: 1,
cutting soybean straws, mixing the
cut soybean straws with
urea and
distilled water to obtain a mixture, carrying out
ultrasonic oscillation on the mixture, then transferring the mixture into a container, and
drying the mixture in a
drying oven to obtain
urea-loaded straws; and 2, putting the obtained
urea-loaded
straw into a tubular furnace into which
nitrogen is introduced for heating, then taking out the
straw,
grinding, sieving, mixing the sieved material with alkali liquor, activating, cleaning, finally putting the cleaned sample into a
drying oven, and drying until the
mass is constant, thereby obtaining the nitrogen-rich
biochar. The nitrogen-rich biochar prepared by the invention can adsorb
oxytetracycline (OTC) and Cu (II) at the same time.