Sonocatalytic degradation of methyl orange in the presence of TiO2 catalysts and catalytic activity comparison of rutile and anatase

Abstract

Rutile and anatase titanium dioxide (TiO(2)) powders were used as sonocatalysts for the degradation of methyl orange which was used as a model compound. Ultrasound was used as an irradiation source. It was found that the sonocatalytic degradation ratios of methyl orange in the presence of TiO(2) powder were much better than ones without any TiO(2), but the sonocatalytic activity of rutile TiO(2) particles was obviously higher than that of anatase TiO(2) particles. Although there are many factors influencing sonocatalytic degradation of methyl orange, the experimental results show that the best degradation ratio of methyl orange can be obtained when the experimental conditions of the initial methyl orange concentration of 10 mg/l, rutile TiO(2) added amount of 500 mg/l, ultrasonic frequency of 40 kHz, output power of 50 W, pH=3.0 and 40 degrees C within 150 min were adopted. In addition, the catalytic activity of reused rutile TiO(2) catalyst was also studied and found to be better than new rutile TiO(2) catalyst sometimes. All experimental results indicated that the method of the sonocatalytic degradation of organic pollutants in the presence of TiO(2) powder was an advisable choice for treating non- or low-transparent organic wastewaters.

Reduction of COD of Textile Industry Waste Water by Using Acoustic Cavitation Coupled with Advanced Oxidation Processes

“…Figure 4. Effect of pH on the reduction of COD of textile industry waste water using acoustic cavitation Table 4 shows that the reduction of COD of textile industry waste water is very rapid under acidic pH 3, 25.83 % reduction of COD of textile industry waste water was obtained at constant reaction temperature (28 ± 3 °C), constant sonicationfrequency 20 kHz, 800W sonication power, 60 % duty cycle and 400 ml of textile industry waste water.At lower pH (acidic), the oxidation capacity of hydroxyl radicals is high as compared to the higher pH (basic) [44][45][46]. To increase the generation of free radicals, the combination of ultrasound with hydrogen peroxide looks to be a promising option.…”

DEGRADASI SENYAWA PARAQUAT DALAM PESTISIDA GRAMOXONE® SECARA FOTOLISIS DENGAN PENAMBAHAN TiO2-ANATASE

“…Dengan cahaya Ultra Violet kebanyakan polutan organik dapat dioksidasi menjadi CO2 dan H2O [3] . TiO2-anatase merupakan katalis yang efektif digunakan untuk degradasi senyawa-senyawa organik toksik seperti zat warna [4][5][6][7][8][9][10][11][12][13][14] dan pestisida [15][16][17] . Untuk itu dilakukan degradasi senyawa paraquat dalam pestisida Gramoxone secara fotolisis dengan penambahan TiO2-anatase.…”

Potential uses of titanium dioxide in conjunction with ultrasound for improved disinfection

“…The application of TiO 2 under US seemed to be an efficient method for enhancing the degradation of hazardous materials [24][25][26]. While the detailed mechanisms have not been clarified yet, the possible roles of OH radicals in the US/TiO 2 -induced degradation of hazardous materials were proposed using several OH radical scavenging agents.…”