The invention provides a method for removing nano-
metal powder surface anions. The method comprises the steps that 1, nano-
metal powder obtained through a
liquid phase reduction method is washed with pure water and centrifugally separated 2-3 times; 2, ultrasonic
waves with the certain power and frequency are used for
processing the wet nano-
metal powder for 15-30 min with stirring, and the processed wet nano-
metal powder is added with
ammonium bicarbonate or
ammonium hydrogen sulfite, then sufficiently stirred, processed in an ultrasonic mode, added with pure water and centrifugally separated; 3, the wet nano-
metal powder is washed with pure water and centrifugally separated, washing is stopped after the pH value of supernatant liquid is measured to be smaller than or equal to 9, and the supernatant liquid is poured out; 4, mercaptan is added under the effect of stirring and ultrasonic
waves, and stirring and ultrasonic
processing continue to be carried out for 15-60 min, then, pure water is added, and
centrifugal separation is carried out after sufficient stirring and ultrasonic wave decentralized
processing; and 5, the nano-
metal powder is washed with organic solution, centrifugally separated 2-3 times, then placed into a high-temperature
hydrogen reduction furnace, added with
hydrogen and dried at 200-300 DEG C, thereby forming the needed product. According to the method, the design is reasonable, technological conditions are moderate and operation is easy. The anion adsorption amount of the nano-metal powder processed by the method is greatly reduced.