Rhodamine B In Aqueous Solution Research Articles

Chemical Potency of Cobalt Doped Modified Graphite Electrode Prepared by Electrochemical Method and its Application in Degrading Solution of Rhodamine-B dye

Primary goal of the present study is to progress a methodological framework for Rhodamine-B dye degradation using cobalt doped graphite modified electrode in aqueous solution by electrochemical method. This is environmentally friendly method. Rate study for Rh-B dye degradation under various parameters like concentration, applied current and temperature were studied and compared between Graphite electrode and Cobalt graphite electrode. Ultra Violet-Visible spectral data and Chemical oxygen demand values are evident for the complete degradation of Rhodamine-B in aqueous solution during anodic oxidation using the modified Co/graphite electrode. The dye degradation efficiency for Cobalt graphite modified electrode (Co/GME) increases by 77% compared to graphite electrode. The COD values decreases to ~98% than the initial COD after degradation with Co/GME. Increase in applied current, temperature increases the rate of degradation and follows first order kinetics up to 60% of the reaction. Hydroxyl (.OH) free radicals are produced by advanced oxidation processes (AOPs), which are attack the dye molecules and cause them to degrade. SEM/EDAX is used to observe the formation of cobalt layer in the rod of graphite. Under various laboratory settings ICE values were computed, it shows that Cobalt doped graphite modified electrode acts as a good anode to degrade Rh-B dye and it converted into CO2, H2O, and other basic inorganic salts. This procedure is straightforward, inexpensive, and can be used to treat wastewater that contains organics.

Surfactant regulated aggregation-induced emission of tetraphenylethene-based tetracationic salt for the construction of light harvesting supramolecular system

Fluorescence resonance energy transfer (FRET) is an efficient optical molecular scale that has been widely used in many fields, and aggregation-induced emission (AIE) luminescent materials show great potential in constructing FRET systems. In this paper, an efficient supramolecular polymer of AIE was prepared in aqueous solution based on tetraphenylethene-based tetracationic salt molecule (1) with AIE properties, using the hydrophobic effect and electrostatic interaction with sodium dodecyl sulfonate (AS). Then, based on supramolecular aggregate (1-AS) and Rhodamine B (RB) dye, the efficient FRET system was prepared in aqueous solution with 1-AS as energy donor and RB as energy acceptor. The Stokes shift of the system can reach 208 nm, and the fluorescence intensity of RB aqueous solution with the same concentration increased 11.80 times. Moreover, the energy transfer efficiency and the antenna effect value reached 77.5%, 14.3, respectively. The method based on simple AIE donor to achieve efficient luminescence of dye molecules is of great significance for the realization of efficient light-trapping system of aqueous solution in practical applications.

Two-step process to produce porous carbon nitrides as efficient photocatalysts to degrades organic pollutants

Polymeric carbon nitride (p-C3N4) has shown excellent properties for various reactions as photocatalysts under the irradiation of visible light. This work reports the development of a new route to produce porous carbon nitride materials using two-step process. The process consists of chemical oxidation of p-C3N4 powders and following thermal treatment of the oxidized materials at 610 ℃. The resulting material (oxidized p-C3N4 after thermal treatment, OCN-T) shows an excellent photocatalytic activity for degrading an organic pollutant, rhodamine B (RhB). Under the irradiation of visible light, RhB in aqueous solution is completely removed within 1 hr. Morphological, chemical, and photophysical characterizations reveal that OCN-T contains higher surface areas and visible-light-absorption ability, and longer lifetime of photoexcited charge carriers than control samples. These features reveal that the two-step process is beneficial to produce efficient photocatalysts using visible light.

Fabrication of Nano Iron Oxide-Modified Biochar from Co-Hydrothermal Carbonization of Microalgae and Fe(II) Salt for Efficient Removal of Rhodamine B.

Dye adsorption by magnetic modified biochar has now received growing interest due to its excellent adsorption performance and facile separation for recycling. In this study, nano iron oxide–modified biochar was fabricated via the successive hydrothermal-pyrolyzing method using Chlorella vulgaris (Cv) and FeSO4·7H2O as raw materials, and its adsorption on Rhodamine B (RhB) in aqueous solution was studied. Multiple techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET), vibrating sample magnetometry (VSM) and X-ray photoelectron spectroscopy (XPS) were employed to comprehensively characterize the structure, morphology and physicochemical properties of the adsorbent. The as-synthesized nano iron oxide–modified biochar (CBC-Fe(II)) exhibited a large surface area (527.6 m2/g) and high magnetic saturation value (13.7 emu/g) to facilitate magnetic separation. Compared with CBC and CBC-Fe(III), CBC-Fe(II) exhibited superior adsorption ability towards RhB in aqueous solution, with a maximum adsorption capacity of 286.4 mg/g. The adsorption process of RhB onto CBC-Fe(II) was well described by the pseudo-second-order kinetic model and Langmuir isotherm model, indicating monolayer chemisorption behaviors for the adsorption system. Facile preparation, great adsorption performance and magnetic recovery properties endow CBC-Fe(II) to be a promising adsorbent for dye removal.

Characterization of submicro-sized Ag/ZnO particles generated using the spray pyrolysis method

Environmental issues caused by the rapid industrialization and urbanization of modern society are a serious problem. For example, conventional wastewater treatment technologies such as adsorption, coagulation, and filtration are expensive and cannot completely treat the discharge of organic pollutants in industrial wastewater. A promising alternative is the decomposition treatment of organic pollutants using an eco-friendly metal oxide photocatalyst. However, the rapid recombination of excited electron-holes limits the photolytic activity of semiconductor photocatalysts. This study investigates the inhibition of electron-hole recombination by supporting Ag nanoparticles on a ZnO photocatalyst. Ag/ZnO particles are generated under various conditions using ultrasonic spray pyrolysis. XRD analysis confirms the presence of Ag and ZnO crystal peaks in the generated particles. EDX mapping and STEM images show that Ag nanoparticles are well dispersed in ZnO. The photolysis rate of organic dye (rhodamine-B) is faster than that of ZnO in all Ag/ZnO particles, and particles with a 0.2 mass% silver nitrate supported on ZnO particles exhibit twice the photolysis activity of P25. Additionally, the optimal photolysis activity in 100 mL of 5 mg/L rhodamine-B aqueous solution with 10 mg of Ag/ZnO particles are confirmed and had excellent persistence and stability even during 7 reuses.

Synthesis, characterization, and visible-light photocatalytic activity of transition metals doped ZTO nanoparticles

Transition metals doping has been proved to be a feasible way for tuning the physical properties on the surface and bulk of nanomaterials and also for the good performance in decontamination of emerging pollutants. In this context, doped samples of zinc tin oxide or zinc stannate nanoparticles (ZTO NPs) by several transition metals were synthesized in order to enhance the optical absorbance with the aims of reducing the band gap and therefore ameliorated their photocatalytic activity. They were characterized by the X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy, Raman spectroscopy and photoluminescence. The XRD patterns and the microscopic observations showed the formation of spherical nanoparticles with an average size of about 30 nm and highly pure ZTO phase with an inverse spinel structure. The Raman spectra were dominated by bands relatives to the F2g (2) and A1g symmetries modes of inverse spinel structure. The band gap Eg is estimated to be 3.75 eV for the undoped sample, and 3.67, 3.64, 3.78 and 3.21 eV, for 2% Fe, 2% Mg, 2% Gd, and 2% Mn doped ZTO samples, respectively.Furthermore, the undoped ZTO NPs have the intrinsic problem of recombination of photogenerated charge carriers. We have shown that the reduction of the band gap and oxygen vacancies resulting from the doping effect could be a useful tool for trapping and avoid the recombination of electrons coming from photosensitized rhodamine B (RhB) under visible light irradiation. Owing to the structural advantages and low band gap, 2% Mn doped ZTO NPs, with the kinetic rate constants k of 0.024 min−1, show enhanced performance for the elimination of RhB in aqueous solution compared to undoped and other doped ZTO NPs.

Self-Assembled Nanomaterials Based on Complementary Sn(IV) and Zn(II)-Porphyrins, and Their Photocatalytic Degradation for Rhodamine B Dye.

A series of porphyrin triads (1–6), based on the reaction of trans-dihydroxo-[5,15-bis(3-pyridyl)-10,20-bis(phenyl)porphyrinato]tin(IV) (SnP) with six different phenoxy Zn(II)-porphyrins (ZnLn), was synthesized. The cooperative metal–ligand coordination of 3-pyridyl nitrogens in the SnP with the phenoxy Zn(II)-porphyrins, followed by the self-assembly process, leads to the formation of nanostructures. The red-shifts and remarkable broadening of the absorption bands in the UV–vis spectra for the triads in CHCl3 indicate that nanoaggregates may be produced in the self-assembly process of these triads. The emission intensities of the triads were also significantly reduced due to the aggregation. Microscopic analyses of the nanostructures of the triads reveal differences due to the different substituents on the axial Zn(II)-porphyrin moieties. All these nanomaterials exhibited efficient photocatalytic performances in the degradation of rhodamine B (RhB) dye under visible light irradiation, and the degradation efficiencies of RhB in aqueous solution were observed to be 72~95% within 4 h. In addition, the efficiency of the catalyst was not impaired, showing excellent recyclability even after being applied for the degradation of RhB in up to five cycles.

Photoelectrocatalytic degradation of rhodamine B pollutant with a novel zinc phosphate photoanode

The present work evaluates the efficiency of Zn3(PO4)2 (ZnP) thin films photoanode for the removal of Rhodamine B (RhB) pollutant. ZnP has been electrodeposited on fluorine-doped tin oxide (FTO) substrate using the cathodic electrodeposition technique. The photoelectrochemical (PEC) properties of this material have been investigated using chronopotentiometry, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The photoanode was characterized by means of X-Ray diffraction (XRD) and scanning electron microscopy (SEM) which revealed that the structures and morphologies of the electrodeposited Zn3(PO4)2 films depended on the applied current densities and deposition times. The PEC activity of ZnP was investigated through the destruction of 10 mg/L of RhB aqueous solution containing 0.1 mol/L NaCl, 99 % of reduction was observed during 30 min of reaction time. Four consecutive experiments using the same photoanode have been carried out and the PEC activity was not reduced which signified the high stability of the elaborated ZnP. The obtained results have shown that the prepared photoanode exhibits photoactivity and can be used for the photo-assisted electrolysis for organics degradation in aqueous effluents.

Activated carbon immobilized WO3 nanocuboids: Adsorption/photocatalysis synergy for the enhanced removal of organic pollutants

Herein, we fabricated activated carbon (AC) immobilized WO3 nanocuboids (AC-WO3) as an efficient and green photocatalyst via simple hydrothermal method. AC-WO3 shows great potential for the removal of stable rhodamine B (RhB) dye in aqueous solution under visible light. The large surface area of the AC-WO3 nanocomposites brought numerous active sites for the adsorption, consequently, for photodegradation of RhB dye. The characterization results established that the prepared material has crystalline orthorhombic structure, nanosized cuboids shape like morphology, visible light responsive nature, thermo stability and smaller particle size with high specific surface area. Adsorption isotherm studies revealed homogeneous surface adsorption with Langmuir adsorption isotherm. Study on adsorption kinetics confirms that adsorption of dye on AC-WO3 follows the second order kinetic model. AC-WO3 nanocomposites exhibit enhancing synergistic effect of adsorption and photodegradation ability for removing RhB in aqueous solution.

Degradation of Rhodamine B in aqueous solution by laser cavitation

A novel method of laser cavitation (LC) was proposed for degrading organic dye wastewater. Rhodamine B (RhB) aqueous solution was employed as the simulated organic dye wastewater, and a LC system was designed to conduct the experiments of degrading RhB. The effects of laser energy, initial concentration and cavitation time on the degradation were investigated. Moreover, the degradation kinetics, degradation mechanism and energy efficiency were analyzed. The experimental results indicate that RhB aqueous solution can be degraded effectively by LC and the degradation follows the pseudo-first-order kinetics. The extent of degradation increases by 27.6% with the rise of laser energy (50-100mJ) while it decreases by 7.8% with increasing the initial concentration from (20-40mg/L), but RhB can not be degraded when exceeding 100mg/L. The degradation extent of RhB at 100mJ and 20mg/L for 3h is 81.11%, and the RhB solution is almost completely degraded at 150mJ (98.4%). The degradation velocity of RhB rises firstly and then decreases as the cavitation time increases. The degradation of RhB by LC can be attributed to the N-de-ethylation and chromophore cleavage caused by oxidation of hydroxyl (OH) radical and thermal decomposition. LC has a higher energy efficiency compared with other methods and is more energy efficient at lower laser energy.

Fabrication of Z-scheme MoO3/Bi2O4 heterojunction photocatalyst with enhanced photocatalytic performance under visible light irradiation

Constructing Z-scheme heterojunction to improve the separation efficiency of photogenerated carriers of photocatalysts has gained extensive attention. In this work, we fabricated a novel Z-scheme MoO3/Bi2O4 heterojunction photocatalyst by a hydrothermal method. XPS analysis results indicated that strong interaction between MoO3 and Bi2O4 is generated, which contributes to charge transfer and separation of the photogenerated carriers. This was confirmed by photoluminescence (PL) and electrochemical impedance spectroscopy (EIS) tests. The photocatalytic performance of the as-synthesized photocatalysts was evaluated by degrading rhodamine B (RhB) in aqueous solution under visible light irradiation, showing that 15% MoO3/Bi2O4 (15-MB) composite exhibited the highest photocatalytic activity, which is 2 times higher than that of Bi2O4. Besides, the heterojunction photocatalyst can keep good photocatalytic activity and stability after five recycles. Trapping experiments demonstrated that the dominant active radicals in photocatalytic reactions are superoxide radical (•O2−) and holes (h+), indicating that the 15-MB composite is a Z-scheme photocatalyst. Finally, the mechanism of the Z-scheme MoO3/Bi2O4 composite for photo-degrading RhB in aqueous solution is proposed. This work provides a promising strategy for designing Bi-based Z-scheme heterojunction photocatalysts for highly efficient removal of environmental pollutants.

Photocatalytic decomposition of rhodamine B by newly designed one-dimension ZnO using chemical method

High quality and mono-dispersed ZnO nanowire and nanorod were firstly synthesized using co-precipitation method without using any organic solvents in the whole preparation process, which is consistent with the development of green chemistry and also can be used for large-scale production. The co-precipitation method is so popular with us that it is conducive to control and industrialize, which is also useful to save energy and protect our environment in part because we never utilize organic solvents and even ethanol in fabricating one-dimension (1D) ZnO. Although the focus here will be on the preparation of nanowired and nanoroded ZnO, we also explore the reaction mechanisms for semiconductor ZnO and commit to provide a prospective blueprint for how understanding growth mechanisms can be used to synthesize other one-dimensional metal oxide with environmental friendly method. As a semiconductor, it can be used in the field of the photocatalytic property, which was tested by the degradation of rhodamine B (RhB) solution. 1D ZnO nanowire products exhibit a high rate degradation of 10 mg L−1 RhB aqueous solution and achieve almost complete degradation of RhB from aqueous solution under light resource within 60 min.

Reduced Graphene Oxide-Doped Ag3PO4 Nanostructure as a High Efficiency Photocatalyst Under Visible Light

A novel photocatalyst Ag3PO4/PDA (Polydopamine)/r-GO (reduced-graphene oxide) has been successfully prepared by a solvent hydrothermal method. The composite photocatalytic material was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), Raman spectra, X-ray photoelectron spectrometer (XPS) and X-ray energy dispersive spectrometry (EDS). Ag3PO4/PDA/r-GO showed a significantly enhanced photocatalytic activity in the degradation experiment of MB and RhB aqueous solution compared with pure Ag3PO4. The degradation rates of MB (Methylene blue) and RhB (Rhodamine B) aqueous solution were 96.8% and 92% in the examination with 15 min under visible light, respectively. At the same time the stability of composite material was higher than pure Ag3PO4. The improvement in photocatalytic performance is attributed to the larger specific surface area, higher absorption capability for visible-light, and most important, the r-GO could act as a charge bridge to accelerate the transfer of electron. This work is expected to provide a promising approach for improving the photocatalytic performance and further utilization of photosensitive semiconductors.

Tris(N-methylferrocenyl-N-(2-phenylethyl)dithiocarbamato-S,S′)cobalt(III) for anion sensing and preparation of cobalt-iron sulfide nanoparticles: A new photocatalyst for the degradation of dyes

Tris(N-(pyrrol-2-ylmethyl)-N-butyldithiocarbamato-S,S′)cobalt(III) (1) and tris(N-methylferrocenyl-N-(2-phenylethyl)dithiocarbamato-S,S′)cobalt(III) (2) have been synthesized and characterized by elemental analysis and spectroscopy (IR, UV-vis and NMR). The elemental analysis and IR, 1H and 13C NMR spectra are consistent with the formation of the cobalt(III) complexes with dithiocarbamate ligands. The anion binding properties of 1 and 2 based on host-guest interaction have been examined with the use of cyclic voltammetry.This study showed that both complexes preferred to bind with I-compared to other halides. 2 has been used as precursors for the preparation of cobalt-iron sulfide nanoparticles. TEM image of cobalt-iron sulfide nanoparticles showed that the particles are spherical. The elemental compositions of the nanoparticles were confirmed by energy dispersive X-ray spectroscopy. IR spectral studies on nanoparticles confirm the presence of capping agent (triethylenetetramine). The nanoparticles were explored as photocatalysts to study the degradation of dyes using methylene blue and rhodamine-B in aqueous solution under UV irradiation. The cobalt-iron sulfide works as an efficient photocatalyst for degradation of rhodamine-B.

The preparation and photocatalytic performance research of CdSe and wool ball-like GO/CdSe microspheres

Different morphologies of CdSe and GO (graphene oxide)/CdSe microspheres like wool ball and walnut shape have been made through hydrothermal method using CTAB as surfactant. X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), X-ray energy dispersive spectrometer (EDS), scanning electron microscope (SEM), Raman spectra, and UV–vis absorption spectrum, were used to intensively investigate the structures, morphologies, chemical compositions and optical properties of CdSe and GO/CdSe microspheres. The results of XRD revealed that GO/CdSe microspheres have lead-zinc mineral structure. The results of XRD, EDS, XPS and Raman spectra showed that GO/CdSe microspheres were grown on GO sheets. Also UV–vis absorption spectrum indicated that GO/CdSe microspheres enhanced absorbance in UV light region and visible light region. Through comparative experiments, the results showed that pH = 4 is the optimal pH value for degrading Rhodamine B (RhB) solution. To study the photocatalytic performance of GO/CdSe microspheres, we catalyzed the degradation of RhB aqueous solution irradiated by visible light. The photocatalytic results showed that the wool ball-like GO/CdSe microspheres exhibited better photocatalytic activity than rough CdSe.

Synthesis of flower‐like CeO 2 /BiOCl heterostructures with enhanced ultraviolet light photocatalytic activity

Flower-like CeO 2 /bismuth oxychloride (BiOCl) heterostructures were successfully prepared by a simple two-step solvothermal/hydrothermal method. The prepared materials were characterised via powder X-ray diffraction measurements, scanning electron microscopy, energy dispersive spectrometry, transmission electron microscopy and ultraviolet-vis diffuse reflectance spectra. Photocatalytic activities of the materials in the degradation of rhodamine B (RhB) were studied. The results showed that all of the materials were successfully prepared. In particular, the BiOCl looks like a cluster of chestnut balls and the CeO 2 /BiOCl composite showing a flower-like morphology. Compared with the pure BiOCl or CeO 2 , the CeO 2 /BiOCl composite showed higher photocatalytic activity for degradation of RhB in aqueous solution under ultraviolet light irradiation.

Ultrasound assisted synthesis of Bi2NbO5F/rectorite composite and its photocatalytic mechanism insights

Enhancing the adsorbability of the photocatalysts is an effective way to improve the photocatalytic performance. Herein, we firstly synthesized a novel Bi2NbO5F/rectorite (BF/R) composite photocatalyst with high adsorption capacity via the ultrasound assisted route. The X-ray photoelectron spectrometer (XPS) analysis has demonstrated that the Bi2NbO5F and rectorite were connected with each other by weak chemical bonds. The introduced rectorite in the composite provided rich adsorption active sites for the adsorption of rhodamine B (RhB). The catalytic activity of the BF/R catalyst was evaluated by degrading RhB (5 mg/L) under UV-light irradiation. The BF/R composite with 32% rectorite exhibited the best photocatalytic degradation efficiency for degrading RhB in aqueous solution, which was 6.6 times higher than that of the bare BF sample. The improved activity of the BF/R composite can be ascribed to its strong adsorbability and enhanced light absorption. More importantly, the BF/R catalyst still showed good stability and high activity for degrading RhB after four recycles. Lastly, a possible photocatalytic mechanism on the BF/R composite was proposed. This work would provide helpful insights into the synthesis of the clay combined with Bi-based adjustable structure materials via ultrasound method.

Structural variations in zinc(II) complexes with N,N-di(4-fluorobenzyl)dithiocarbamate and imines: New precursor for zinc sulfide nanoparticles

Bis(N,N-di(4-fluorobenzyl)dithiocarbamato-κ2S,S′)zinc(II) (1), bis(N,N-di(4-fluorobenzyl)dithiocarbamato-κ2S,S′)(pyridine-κN)zinc(II) (2), (μ-4,4′-bipyridine-κ2N,N′)bis[bis(N,N-di(4-fluorobenzyl)dithiocarbamato-κ2S,S′)zinc(II)] (3) and (2,2′-bipyridine-κ2N,N′)bis(N,N-di(4-fluorobenzyl)dithiocarbamato-κS,S′)zinc(II) (4) were prepared and characterized by elemental analysis, spectroscopy (IR, 1H and 13C NMR) and their structures were elucidated by X-ray crystallography. The centrosymmetric dinuclear structure of 1 features both bridging and chelating dithiocarbamate ligands to that a distorted trigonal bipyramidal S5 coordination geometry results. The coordination geometry of zinc(II) in 2 and both zinc(II) in the dinuclear complex 3 is an intermediate between tetragonal pyramidal and trigonal bipyramidal. In complex 4, the resulting N2S4 donor set defines a distorted octahedral geometry. Addition of imines (pyridine, 4,4′-bipyridine and 2,2′-bipyridine) to the complex 1 affects the ZnS distances and SZnS angles. The optimized geometry, HOMO-LUMO in the ground state and MEP have been calculated for 1 and 2. MEP analysis support the substantial contribution of the resonance structure RR′-N+CS22− to the description of their structures on the complexes 1 and 2. Quantification of the intermolecular interactions present in 1–4 was realized by Hirshfeld surface analysis. Zinc sulfide nanoparticles were prepared from 1 and characterized by PXRD, SEM, TEM, EDAX and DRS. The PXRD study showed that the nanoparticles is composed of cubic phase of zinc sulfide. Photocatalytic activity of as-prepared ZnS was tested by examining the degradation of rhodamine-B in aqueous solution under UV light illumination.

Phase control synthesis of α, β and α/β Bi2O3 hetero-junction with enhanced and synergistic photocatalytic activity on degradation of toxic dye, Rhodamine-B under natural sunlight

Nano particles of a few α/β Bi2O3 hetero-junctions of various compositions synthesized by one- pot hydrothermal method, exhibit exceptional and synergistic photo-catalytic activity for the degradation of Rhodamine-B in aqueous solution under natural sunlight. Pure α and pure β Bi2O3 are also synthesized by control post heating of synthesized hetero-junction. The nano-materials were characterized by diffraction (XRD), microscopic and spectroscopic techniques. The XRD reveals α-β phase hetero-junctions of Bi2O3 are made of α-Bi2O3 and β-Bi2O3 with average dimensions within 13–113 and 5–71 nm respectively and having band gap range of 2.4– 2.9 eV. The spectrophotometrically determined % degradation of the dye and associated rate constant on the best hetero-junction are increased by 4.5(/2.1) and 3.3(/1.2) times than these on pure α (/β). The effects of operational parameters and trapping agents have been analyzed. The maximum removal of the dye was achieved up to 99.6% in 3 h using 0.5 g/L photo-catalyst at pH 3. The reusability test shows that the photo-catalytic activity is retained excellently due to change in chemical nature of the catalyst from α -Bi2O3 to β-Bi2O3, Bi2O2CO3 and BiOCl. A suitable mechanism is proposed.

Degradation of organic wastewater by hydrodynamic cavitation combined with acoustic cavitation

In this paper, the decomposition of Rhodamine B (RhB) by hydrodynamic cavitation (HC), acoustic cavitation (AC) and the combination of these individual methods (HAC) have been investigated. The degradation of 20 L RhB aqueous solution was carried out in a self-designed HAC reactor, where hydrodynamic cavitation and acoustic cavitation could take place in the same space simultaneously. The effects of initial concentration, inlet pressure, solution temperature and ultrasonic power were studied and discussed. Obvious synergies were found in the HAC process. The combined method achieved the best conversion, and the synergistic effect in HAC was even up to 119% with the ultrasonic power of 220 W in a treatment time of 30 min. The time-independent synergistic factor based on rate constant was introduced and the maximum value reached 40% in the HAC system. Besides, the hybrid HAC method showed great superiority in energy efficiency at lower ultrasonic power (88–176 W). Therefore, HAC technology can be visualized as a promising method for wastewater treatment with good scale-up possibilities.