▎ 摘　　要

NOVELTY - Preparation of magnetic aerobic granular sludge-graphene-multi-walled carbon nanotube composite adsorbent involves ultrasonically dispersing graphene oxide and multi-walled carbon nanotubes into water, stirring, drying, dissolving in acetic acid, ultrasonically treating, adding ferroferric oxide particles, mechanically stirring, adding paraffin, stirring, adding glutaraldehyde and dry granular sludge, stirring in oil bath, adding sodium hydroxide, adjusting pH, continuously stirring, washing with petroleum ether, ethanol and deionized water to obtain black solid and vacuum-drying. USE - Method for preparing magnetic aerobic granular sludge-graphene-multi-walled carbon nanotube composite adsorbent used for removing cationic dye in water (claimed). ADVANTAGE - The adsorbent has increased adsorption sites, large specific surface area, simple preparation process, low cost, high adsorption capacity, easy separation, can be reused, and does not cause secondary pollution. DETAILED DESCRIPTION - Preparation of magnetic aerobic granular sludge-graphene-multi-walled carbon nanotube composite adsorbent comprises: (A) laboratory culturing aerobic granular sludge in sequencing batch reactor, washing with super-purified water for 3-5 times, drying at 100-110 degrees C, grinding and sieving to powder of 60-160 mesh to obtain dry granular sludge; (B) dissolving 0.5-1.5 g ferric chloride hexahydaate in 10-30 mL ethylene glycol, adding 1-5 g sodium acetate and 5-15 mL ethylenediamine, stirring for 10-50 minutes, putting in reaction kettle, heating at 200 degrees C for 6-9 hours, cooling to room temperature and repeatedly washing with super-purified water until neutral to obtain ferroferric oxide particles; (C) mixing 0.2-0.5 g graphite and 1.5-2.0 g potassium permanganate, adding 30-40 mL concentrated sulfuric acid and 3-5 mL phosphoric acid, putting to three-mouth flask, reacting in oil bath at 40-60 degrees C for 10-14 hours, pouring solution on ice, slow magnetic stirring, adding 0.3-0.5 mL hydrogen peroxide, reacting for 20-40 minutes, centrifuging, washing with hydrochloric acid, ethanol and diethyl ether and vacuum-drying solid sample; and (D) ultrasonically dispersing 0.1-0.3 g graphene oxide and multi-walled carbon nanotubes into 20-40 mL water for 20-40 minutes, stirring for 20-40 minutes, drying for 24 hours, dissolving in acetic acid, ultrasonically treating at room temperature for 1-3 hours, adding ferroferric oxide particles, mechanically stirring for 1-3 hours, adding 1-5 mL paraffin as emulsifier, stirring for 0.1-1 hour, adding 1-5 mL glutaraldehyde and 0.1-0.6 g dry granular sludge, stirring in oil bath at 30-70 degrees C for 1-3 hours, adding 1-3 mol/L sodium hydroxide, adjusting pH to 8.0-11.0, continuously stirring at 70-90 degrees C for 30-90 minutes, washing with petroleum ether, ethanol and deionized water until neutral to obtain black solid and vacuum-drying at 40-60 degrees C.