Synthesis of TiO 2 /ramie fiber composite and its photocatalytic effect on the degradation of a dye in wastewater

TiO 2 was prepared by a hydrothermal method. It was chemically combined with carboxymethyl cellulose prepared from biodegradable ramie fiber to obtain the TiO 2 /ramie fiber composite. The TiO 2 /ramie fiber composites were characterized by an X-ray diffractometer, an environmental scanning electron microscope, and a Fourier-transform infrared spectra. The results indicate that TiO 2 is chemically combined with ramie fiber, and it can be reused more than five times without obvious TiO 2 loss. The photocatalytic performances of TiO 2 and TiO 2 /ramie fiber composite used to degrade both a methyl orange (MO) anionic dye and a rhodamine B (RB) cationic dye solution indicate that the photocatalytic activities of TiO 2 for the degradation of the above described solutions are greatly improved when the TiO 2 is dispersed on ramie fiber. When 0.5 g of the TiO 2 /ramie fiber composite is added to a dye solution for 3 h, the degradation rates for the initial concentrations (20 mg/L of MO and 12 mg/L of RB) are greater than 90 %. The photocatalytic degradation of MO can be described as a zeroth order reaction.