▎ 摘　　要

NOVELTY - Photocatalytic titanium dioxide oxide graphene straw composite adsorbent, is claimed. The composite adsorbent is prepared by using titanium dioxide, graphene oxide and straw core powder as raw materials to adhere titanium dioxide to the surface of graphene oxide and activated straw core powder by self-assembly. USE - The composite adsorbent is useful in catalyze degradation to remove cationic dye, i.e. methylene blue, methyl orange, rhodamine b and pyro red (all claimed). ADVANTAGE - The composite adsorbent: can realize removal of cationic dye in small amount; simple preparation technique, high removing rate, excellent absorption effect, simple and easy adsorption process, convenient separation, no secondary pollution; and realizes repeated use. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) preparing composite adsorbent, comprising (1a) drying the straw at 40 degrees C for 24 hours, peeling off the straw epidermis, cutting the straw core into small sections of 1.5-2.5 cm, crushing, and sieving through 100 mesh sieve to obtain straw core powder, (1b) adding the straw core powder into 10% zinc chloride aqueous solution, where the ratio of material to liquid is 0.05-0.2 g/ml, and stirring in water bath at 75 degrees C for 1 hour to obtain colloid, (1c) suction filtering the colloid, washing three times with absolute ethanol and distilled water, and drying to obtain activated straw core powder, (2a) dispersing 0.2-0.6 pts. wt. titanium dioxide in water ultrasonically for 20 minutes, stirring every 5 minutes in an ultrasonic process to obtain titanium dioxide dispersion having concentration of 0.01 g/ml, (2b) adding suspension containing 0.02-0.04 pts. wt. graphene oxide dropwise into the titanium dioxide dispersion, where the dropping rate is 1 second for 5 seconds, stirring the mixture at 150 revolutions/minute, ultrasonic dispersion for 30 minutes, and stirring once in ultrasonication of every 5 minutes, the ultrasonic power is 50 w, the temperature is 30 degrees C, (2c) adding 0.38-0.76 pts. wt. activated straw core powder to the titanium oxide graphene oxide dispersion, dispersing ultrasonically for 30 minutes, and the ultrasonic process is stirred for every 5 minutes, to obtain dispersion system of titanium dioxide graphene oxide straw core powder, and (2d) freezing the titanium dioxide graphene oxide straw core powder dispersion at -20 degrees C for 12 hours, freeze drying the frozen dispersion system to obtain titanium oxide graphene oxide straw core powder composite adsorbent; and (2) degrading cationic dye by the composite adsorbent, comprising taking 50 ml, 50 mg/l dye solution in the Erlenmeyer flask, adding 50 mg composite adsorbent and shaking in 25 degrees C water bath for 3 hours, allowing to stand for 20 minutes to precipitate the adsorbent, irradiating the dye solution containing the adsorbent under an ultraviolet lamp having a luminous intensity of 27 cd, stirring the mixture for 1 hour with magnetic stirrer rotating at 400 revolutions/minute, allowing to stand, and removing the adsorbent by filtration to obtain degraded dye solution.