▎ 摘　　要

NOVELTY - Preparing graphene aerogel comprises (i) centrifuging oxidized graphene aqueous solution at 12000 revolutions/minutes for 15-60 minutes, and removing the supernatant, adding absolute ethyl alcohol, repeating 10-20 times to obtain the concentration of 0.2-10.0 mg/ml graphite alcohol gel, (ii) carrying out the graphite alcohol gel to in situ hydro-thermal reaction to 100-180 degrees C for 4-12 hours, (iii) immersing graphene hydrogel in solvent, adding distilled water, at the same time, absorbing the mixed solvent contains no mixed solvent until the solution, mixing the mixed solvent by ethanol and acetone, (iv) placing the product into liquid nitrogen to drying for 20-60 hours, (v) placing the graphene aerogel into a tubular furnace, heating rate of 2 degrees C/minutes at 400-600 degrees C in Ar for 2-10 hours to obtain graphene aerogel secondary product and (vi) centering the graphene aerogel secondary product in an ozone atmosphere for 5-30 minutes to obtain the graphene aerogel. USE - The graphene aerogel is useful for adsorbing heavy metal ions in wastewater (claimed). ADVANTAGE - The method has good conductivity, realizes electrochemical desorption, enrichment and recovery of heavy metal ion, and is low energy consumption and water pH is neutral and environmentally friendly. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for use method specifically is as follows: (a) pressing the waste water containing heavy metal ion into filter type column electrode in the system at a flow rate of 0.2-10 ml/minutes and detecting the water heavy metal ion concentration, when the effluent metal ion concentration remains the same, saturating graphene aerogel with adsorption and stopping feeding water and (b) changing the water into pH=2-4 of acidic desorption liquid, connecting with direct current power supply, where the voltage is 1.5-5 V, absorbing the heavy metal ion of the graphene aerogel surface to realize desorption.