A review on heterogeneous sonocatalyst for treatment of organic pollutants in aqueous phase based on catalytic mechanism

Qiu, Pengpeng; Park, Beomguk; Choi, Jongbok; Thokchom, Binota; Pandit, Aniruddha B.; Khim, Jong Seong

doi:10.1016/j.ultsonch.2018.03.003

Cited by 137 publications

(67 citation statements)

References 150 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…AOPs are characterized by the production of reactive oxygen species (ROS) like superoxide radical anion, hydroxyl radical (OH · ), hydrogen peroxide (H 2 O 2 ) and singlet oxygen (O 2 · ), which can quickly oxidize dye molecules present in industrial effluents. Some examples of AOPs include Fenton reaction (involving iron cations Fe 2+ /Fe 3+ and hydrogen peroxide H 2 O 2 ) [3], ozonation [4], photolysis [5], photocatalysis [6], sonolysis [7] and sonocatalysis [8].…”

Section: Introductionmentioning

confidence: 99%

“…This radical generation mechanism is still under investigation, but one of the most probable mechanism is the semiconductor activation due to the intense UV and visible light emission during the cavitation and bubbles collapses [14]. Titanium dioxide (TiO 2 ) is the most widely investigated sonocatalyst and it was found that its sonocatalytic activity is influenced by its crystalline structure and morphology [8]. Some studies obtained that the TiO 2 sonocatalytic activity was higher than of Al 2 O 3 (non-semi-conducting material) suggesting that the photonic and thermal excitation has an important contribution on the overall sonocatalytic activity [15–17].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Sonophotocatalytic degradation mechanisms of Rhodamine B dye via radicals generation by micro- and nano-particles of ZnO

Lops

Ancona

Cesare

et al. 2019

Applied Catalysis B: Environmental

385

148

View full text Add to dashboard Cite

In this work, it is proposed an environmental friendly sonophotocatalytic approach to efficiently treat polluted waters from industrial dyes exploiting ZnO micro- and nano-materials. For the first time, we deeply investigated the generation of reactive oxygen species (ROS) under ultrasound stimulation of different ZnO structures by Electron Paramagnetic Resonance Spectroscopy (EPR). Indeed, five zinc oxide (ZnO) micro- and nano-structures, i.e. Desert Roses (DRs), Multipods (MPs), Microwires (MWs), Nanoparticles (NPs) and Nanowires (NWs), were studied for the Rhodamine B (RhB) sonodegradation under ultrasonic irradiation. The DRs microparticles demonstrated the best sonocatalytic performance (100% degradation of RhB in 180 min) and the highest OH· radicals generation under ultrasonic irradiation. Strikingly, the coupling of ultrasound and sun-light irradiation in a sonophotodegradation approach led to 100% degradation efficiency, i.e. color reduction, of RhB in just 10 min, revealing a great positive synergy between the photocatalytic and sonocatalytic mechanisms. The RhB sonophotocatalytic degradation was also evaluated at different initial dye concentrations and with the presence of anions in solution. It was demonstrated a good stability over repeated cycles of dye treatment, which probe the applicability of this technique with industrial effluents. In conclusion, sonophotocatalytic degradation synergizing sunlight and ultrasound in the presence of DRs microparticles shows a great potential and a starting point to investigate further the efficient treatment of organic dyes in wastewater.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Sonophotocatalytic degradation mechanisms of Rhodamine B dye via radicals generation by micro- and nano-particles of ZnO

Lops

Ancona

Cesare

et al. 2019

Applied Catalysis B: Environmental

385

148

View full text Add to dashboard Cite

show abstract

“…The origin of enhanced nanohybrid sonocatalytic activities comes from the efficient separation of electron–hole pairs, which either directly react water with h + or contribute to forming active species, hydroxyl radicals ( • OH), and superoxide radicals (O 2 •– ) through the reduction of the electron. 22 , 52 …”

Section: Resultsmentioning

confidence: 99%

Synergistic Effects of Carbon Dots and Palladium Nanoparticles Enhance the Sonocatalytic Performance for Rhodamine B Degradation in the Absence of Light

et al. 2020

View full text Add to dashboard Cite

Carbon dot (CD) and palladium nanoparticle (Pd NP) composites are semiconducting materials having tremendous applications in catalysis with suitable band gaps. However, their combination with a suitable polymer matrix in sonophotocatalysis has not been explored. Herein, we have synthesized and characterized a new nanohybrid catalyst from a polyamide cross-linked CD-polymer and subsequent deposition of Pd NPs. A sonocatalytic activity of 99% rhodamine B dye degradation was achieved in mere 5 min in the dark. A model catalyst replacing CDs with benzene and other control studies revealed that the synergistic effects of CDs and Pd NPs enhance the sonocatalytic activity of the nanohybrid catalyst. Interestingly, visible light did not influence the activity significantly. Mechanistic investigations suggest that generation of reactive oxygen species on the surface of the CD–polymer initiated by ultrasound, which is further facilitated by Pd NPs, is the key for remarkable catalytic activity (a rate constant of 0.99 min –1 ). Recyclable heterogeneous catalysts under ambient conditions are promising for exploring sono-assisted dark catalysis for several avenues.

show abstract

“…The reduction in TOC content can be attributed to the photocatalytic generation of ROS [39]. The photocatalysis mechanism is widely explained in the literature [40], but, in summary, when a semiconductor such as titanium dioxide is illuminated by a light of energy (hv) greater than or equal to the band gap energy (E gap ) electrons are excited to the conduction band (CB), leaving a positive hole in valance band (VB) Equation (5) [41].…”

Section: Tio 2 Photocatalysismentioning

confidence: 99%

Organic Degradation Potential of Real Greywater Using TiO2-Based Advanced Oxidation Processes

Alrousan

Afkhami

Bani‐Melhem

et al. 2020

Water

View full text Add to dashboard Cite

In keeping with the circular economy approach, reclaiming greywater (GW) is considered a sustainable approach to local reuse of wastewater and a viable option to reduce household demand for freshwater. This study investigated the mineralization of total organic carbon (TOC) in GW using TiO2-based advanced oxidation processes (AOPs) in a custom-built stirred tank reactor. The combinations of H2O2, O3, and immobilized TiO2 under either dark or UVA irradiation conditions were systematically evaluated—namely TiO2/dark, O3/dark (ozonation), H2O2/dark (peroxidation), TiO2/UVA (photocatalysis), O3/UVA (Ozone photolysis), H2O2/UVA (photo-peroxidation), O3/TiO2/dark (catalytic ozonation), O3/TiO2/UVA (photocatalytic ozonation), H2O2/TiO2/dark, H2O2/TiO2/UVA, H2O2/O3/dark (peroxonation), H2O2/O3/UVA (photo-peroxonation), H2O2/O3/TiO2/dark (catalytic peroxonation), and H2O2/O3/TiO2/UVA (photocatalytic peroxonation). It was found that combining different treatment methods with UVA irradiation dramatically enhanced the organic mineralization efficiency. The optimum TiO2 loading in this study was observed to be 0.96 mg/cm2 with the highest TOC removal (54%) achieved using photocatalytic peroxonation under optimal conditions (0.96 mg TiO2/cm2, 25 mg O3/min, and 0.7 H2O2/O3 molar ratio). In peroxonation and photo-peroxonation, the optimal H2O2/O3 molar ratio was identified to be a critical efficiency parameter maximizing the production of reactive radical species. Increasing ozone flow rate or H2O2 dosage was observed to cause an efficiency inhibition effect. This lab-based study demonstrates the potential for combined TiO2-AOP treatments to significantly reduce the organic fraction of real GW, offering potential for the development of low-cost systems permitting safe GW reuse.

show abstract

A review on heterogeneous sonocatalyst for treatment of organic pollutants in aqueous phase based on catalytic mechanism

Cited by 137 publications

References 150 publications

Sonophotocatalytic degradation mechanisms of Rhodamine B dye via radicals generation by micro- and nano-particles of ZnO

Sonophotocatalytic degradation mechanisms of Rhodamine B dye via radicals generation by micro- and nano-particles of ZnO

Synergistic Effects of Carbon Dots and Palladium Nanoparticles Enhance the Sonocatalytic Performance for Rhodamine B Degradation in the Absence of Light

Organic Degradation Potential of Real Greywater Using TiO2-Based Advanced Oxidation Processes

Contact Info

Product

Resources

About