Hydrothermal Synthesis, Characterization and Photocatalytic Activity of Nanosized TiO_2 Based Catalysts for Rhodamine B Degradation (original) (raw)
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Photocatalytic Removal of Rhodamine B from Aqueous Solutions Using TiO2 Nanocatalyst
J. Appl. Environ. Biol. Sci, 2011
Heterogeneous photocatalysis is an effective treatment method for the removal of toxic pollutants from industrial wastewaters. In this work slurry photoreactor using TiO 2 (Degussa P-25) as catalyst was evaluated for its effectiveness in removing Rhodamine B (RB) from aqueous solutions. The effects of operating conditions such as RB initial concentration, pH value, catalyst loading, and types of UV light irradiation on the removal efficiency were evaluated. The results of experiments indicated that the removal of Rhodamine B increased with increasing the catalyst loading and dye initial concentration. Also the wavelength of the light used for photoactivation has a significant impact on the dye degradation rate; shorter wavelengths lead to faster degradation. The order of degradation rate using different light sources was shown to be UV-C>UV-A>UV-LED. According to experimental data, the photocatalytic degradation of Rhodamine B can be simulated by using pseudo-first-order reaction rate.
INTERNATIONAL SYMPOSIUM ON GREEN AND SUSTAINABLE TECHNOLOGY (ISGST2019)
Zinc oxide (ZnO) and titanium dioxide (TiO2) powders were hydrothermally modified in 10 M sodium hydroxide solutions at 120 °C for 24 hours to alter its morphologies. Hydrothermally treated ZnO and TiO2 showed partially rod-shaped particles and used as catalysts in the photocatalytic degradation of Rhodamine B under UV illumination. The effect of operational parameters on degradation efficiency such as catalyst loading (0.5 g/L to 2.5 g/L), initial dye concentration (2.5 ppm to 12.5 ppm), initial H2O2 concentration (0.1 M to 4.0 M) and solution pH (3 to 11) were studied. ZnO showed better photocatalytic activity as compared to TiO2 because ZnO has a lower bandgap energy and more active electron-hole pairs formation in the system. The optimum conditions were 0.5 M H2O2, 1.5 g/L ZnO suspension and 7.5 ppm Rhodamine B at neutral solution pH. The degradation of Rhodamine B followed pseudo first order reaction, with the apparent rate of reaction, kapp = 0.0501 min-1. An effective, efficient and environmental friendly method to remove organic dye from wastewater was developed and could be implemented in treating various types of organic pollutants.
Materials Technology: Advanced Performance Materials, 2012
Water and energy crisis are two problems that need to attend in the next decay. Lack of adequate fresh water throughout the world special in regions with scarcity of water will affect the social manner. This paper discusses on the life cycle assessment for retrofitting the photocatalytic technology as an alternative waste water treatment. The effect and kinetic of UV and solar irradiation on photocatalytic dynamic reactor using TiO 2-P25 (Degussa) were investigated for removal of rhodamine B (RhB) dye chosen as organic pollutant. The degradation kinetic of RhB is discussed in terms of Longmire model. The results showed that UV irradiation was more efficient than solar irradiation to degrade the RhB dye. The effect of temperature on performance of photo reactor was monitored in 15, 25 and 50uC. The photocatalytic reactor degraded the RhB in warm conditions better than the cool conditions.
Scientific Reports, 2023
The current investigation deals with the simple and ecological synthesis of CaO, MgO, CaTiO 3, and MgTiO 3 for the photocatalytic dilapidation of rhodamine B dye. CaO was procured from chicken eggshell waste by calcination process, while MgO was produced by solution combustion method using urea as a fuel source. Furthermore, CaTiO 3 and MgTiO 3 were synthesized through an easy and simple solid-state method by mixing thoroughly the synthesized CaO or MgO with TiO 2 before calcination at 900 °C. XRD and EDX investigations confirmed the phase formation of the materials. Moreover, FTIR spectra revealed the existence of Ca-Ti-O, Mg-Ti-O, and Ti-O which resembles the chemical composition of the proposed materials. SEM micrographs revealed that the surface of CaTiO 3 is rougher with relatively dispersed particles compared to MgTiO 3 , reflecting a higher surface area of CaTiO 3. Diffuse reflectance spectroscopy investigations indicated that the synthesized materials can act as photocatalysts under UV illumination. Accordingly, CaO and CaTiO 3 effectively degraded rhodamine B dye within 120 min with a photodegradation activity of 63% and 72%, respectively. In contrast, the photocatalytic degradation activity of MgO and MgTiO 3 was much lower, since only 21.39 and 29.44% of the dye were degraded, respectively after 120 min of irradiation. Furtheremore, the photocatalytic activity of the mixture from both Ca and Mg titanates was 64.63%. These findings might be valuable for designing potential and affordable photocatalysts for wastewater purification. Despite being one of the most harmful pollutants, dyes are widely used in the fabric, food, plastic, chemical, and tabloid industries. Their discharge into the aquatic environment has a serious impact on living organisms 1,2. Color reduces sunlight penetration through water, resulting in decreased photosynthetic activity and decreased biota development. In addition, dyes tend to bind metal ions, resulting in micro toxicity in fish and other living things 1,3. Normally, dyes are barely biodegradable and challenging to be eliminated by conventional approaches. In this context, rhodamine B (RhB) which belongs to the xanthene family, is a highly stable cationic dye due to its rigid heterocyclic structure 4. Indeed, the high stability of RhB dye is beneficial for different industrial applications, however, makes its degradation not simple and challenging 5-7. As a result, providing efficient, environmentally friendly, and cost-effective solutions for the breakdown of such contaminants is critical for the long-term viability of green habitats. This has resulted in a diverse range of techniques being employed to extract dyes from
Visible light photoelectrocatalytic degradation of rhodamine B using a dye-sensitised TiO2 electrode
Chemical Papers, 2014
Titanium dioxide is a promising catalyst for application in the photodegradation of organic pollutants in water due to its powerful oxidising property and long-term photostability. This study presents the production of titanium dioxide using the sol-gel process, dye sensitisation of the TiO2 electrode, and the performance of that cell. Sensitisation of titanium dioxide was performed using a dye, i.e., Fe(II)-polypyridyl complexes. The photoelectrocatalytic degradation of rhodamine B (RB) using ITO/TiO2/dye as electrode was investigated via a series of potentials, from +1.0 V to −1.0 V, and at various pH and NaCl concentration values (ITO is indium tin oxide conductive glass). The photoelectrocatalytic degradation of RB was performed with a visible light lamp. The change in the absorbance of RB with various potentials indicated that the absorbance of RB in solution systems with the sensitised TiO2 electrodes decreased with increasing anodic potential bias. The degradation cell exhibi...
Photocatalytic Decomposition of Rhodamine-B Using Scandium and Silver-Modified TiO2 Powders
Advanced Materials Research, 2014
Semiconductor-mediated photocatalytic oxidation is an interesting method for water decontamination and a specially modified TiO 2 is said to be a promising material. This study verified that the synthesis of 1wt%Ag modified-Sc 0.01 Ti 0.99 O 1.995 powder samples prepared by Polymeric Precursor Method is capable of forming a mixture of anatase-rutile phase with high photocatalytic performance. This kind of material is found to have a lower bandgap compared to the TiO 2 -anatase commercial powders, which can be associated to an innovative hybrid modification. The simultaneous insertion of scandium in order to generate a p-type semiconductor and a metallic silver nanophase acting as an electron trapper demonstrated being capable of enhancing the degradation of rhodamine B compared to the commercial TiO 2 . In spite of the different thermal treatments or phase amounts, the hybrid modified powder samples showed higher photocatalytic activity than the commercial ones.
Applied Catalysis B-environmental, 2009
C-, S-, N-, and Fe-doped TiO2 photocatalysts were synthesized by a facile sol–gel method. The structure and properties of catalysts were characterized by N2 desorption–adsorption, X-ray diffraction (XRD), UV–vis spectroscopy, and X-ray photoelectron spectroscopy (XPS). Results revealed that the surface area of the multi-doped TiO2 was significantly increased and the crystallite size was smaller than the pure TiO2 obtained by
A study of process variables for the photocatalytic degradation of rhodamine B
Brazilian Journal of Chemical Engineering, 2007
The photoactivated degradation reaction of rhodamine B (RB) was studied using P-25 TiO 2 (Degussa) as catalyst. Three process variables-temperature, initial pH, and catalyst concentration-were evaluated. Temperature had a slight effect on reaction rate; however, the combined effect of pH and catalyst concentration was greater. pH affected the catalyst particle's adsorption of RB, altering the reaction rate. The concentration of the catalyst was significant only up to 0,65 g L-1. The effect of temperature was studied at optimum pH and 50ºC was found to be the optimum operational temperature. The effect of the presence of a surfactant (sodium dodecylsulfate, SDS) and ionic contaminants (Cland SO 4-) in the reaction system was also studied. The surfactant improved the catalyst's adsorption of RB by more than 80%, increasing the degradation reaction rate as well. The ionic contaminants reduced the reaction rate.
Photodegradation of rhodamine 6G in aqueous solution via SrCrO4 and TiO2 nano-sphere mixed oxides
Journal of Materials Research and Technology, 2013
Nano-sphere TiO 2 and SrCrO 4 (up to 5 mol%) mixed oxides were synthesized by co-precipitation method and investigated as catalyst in the photodegradation of rhodamine 6G (Rh6G) in aqueous solution. SrCrO 4 /TiO 2 oxides were characterized by techniques of powdered X-ray diffraction, EDAX, BET, TEM, SEM and ESR analysis. The photocatalytic activities of degradation of dyes were measured by UV-VIS absorption spectroscopy. The results showed that the mixed oxides of TiO 2 with 1 mole % of SrCrO 4 (SCT1) exhibit a photocatalytic activity 3 times higher than that of P25TiO 2 for oxidation of various dyes (Rh6G, TB, MO and BG) under UV light irradiation (l > 280 nm). Among all these dyes the photodegradation of Rh6G was faster compared to other dyes. The average crystallite sizes, spherical particle sizes and grain sizes of SCT1 were found to be ∼15 nm, 90 ± 5 nm and 100 ± 5 nm, respectively. The EPR spectrum of SCT1 indicated that the ejection of electron helped to degrade the dye molecule faster.
Journal of Hazardous Materials, 2006
PLZT fine powders have been synthesized by a hydrothermal process using lead acetate, lanthanum acetate, zirconium n-propoxide and titanium isopropoxide as starting materials. The synthesis was performed at 200 • C for 8, 12 and 24 h. 4 M KOH was used as a mineralizer to adjust the pH to an optimum value for the mixed precursor solution. After hydrothermal treatment the solid portion was separated out, washed and dried at 100 • C for 12 h, where PLZT fine powders were obtained. PLZT powders were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The PLZT powders were pressed and sintered to obtain high density ceramics, which then were investigated by XRD and SEM. The dielectric properties of the ceramics were investigated by measurements of dielectric constant and dielectric loss as a function of temperature at a fixed frequency.