Sonocatalytic degradation of Acid Blue 92 using sonochemically prepared samarium doped zinc oxide nanostructures

Abstract

Pure and Sm-doped ZnO nanoparticles were synthesized applying a simple sonochemical method. The nanocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) techniques which confirmed the successful synthesis of the doped sonocatalyst. The sonocatalytic degradation of Acid Blue 92 (AB92), a model azo dye, was more than that with sonolysis alone. The 6% Sm-doped ZnO nanoparticles had a band gap of 2.8 eV and demonstrated the highest activity. The degradation efficiency (DE%) of sonolysis and sonocatalysis with undoped ZnO and 6% Sm-doped ZnO was 45.73%, 63.9%, and 90.10%, after 150 min of treatment, respectively. Sonocatalytic degradation of AB92 is enhanced with increasing the dopant amount and catalyst dosage and with decreasing the initial AB29 concentration. DE% declines with the addition of radical scavengers such as chloride, carbonate, sulfate, and tert-butanol. However, the addition of enhancers including potassium periodates, peroxydisulfate, and hydrogen peroxide improves DE% by producing more free radicals. The results show adequate reusability of the doped sonocatalyst. Degradation intermediates were recognized by gas chromatography-mass spectrometry (GC-MS). Using nonlinear regression analysis, an empirical kinetic model was developed to estimate the pseudo-first-order constants (kapp) as a function of the main operational parameters, including the initial dye concentration, sonocatalyst dosage, and ultrasonic power.

Heterogeneous sono-Fenton-like process using martite nanocatalyst prepared by high energy planetary ball milling for treatment of a textile dye

“…The apparent pseudo-first order rate constants (k app ) for the AB92 degradation were estimated from ln (A 0 /A t ) against time (t) plots and presented in Table 3. The A 0 and A stand for the absorbance of the AB92 at the beginning and certain process time, respectively [30]. The straight lines with proper correlation coefficients (R 2 ), which were more than 0.99, proved the proposed kinetic.…”

“…Hence, this method is very appropriate for large scale industrial productions from an economical viewpoint [25,26]. There are a number of studies that have used diverse nanomaterials such as LiF [27], ZnS [28], Cu 2 O [29] and FePt [30] that were formed using the high energy MBM process.…”

Ultrasonically and Photonically Simulatable Bi‐Ceria Nanocubes for Enhanced Catalytic Degradation of Aqueous Dyes: A Detailed Study on Optimization, Mechanism and Stability

“…As shown in Figure S7, increasing the sonocatalytic dosage from 0.5 to 1.25 g/100 ml resulted in increasing the degradation efficiency from 39.9% to 92.8%, respectively. The improved degradation performance, together with increasing the catalytic dosage is because of the producing more active sites for catalytic reaction, increased surface area to interact with dye molecules and creating more nuclei for the formation of cavitation effect ,. However, the sonocatalytic dosage was increased above 1.5 g/100 ml the degradation efficiency was affected.…”

“…The photocatalytic degradation efficiency of the 5BCO catalyst on after every 100 min of each cycle were approximately obtained as 97.4%, 96.3%, 95.5%, 94.2% and 94.1% respectively. The declination in sonocatalytic degradation efficiency by reason of damage occurs on catalytic surfaces using mechanical waves produced during ultrasonic irradiation, protonation of catalytic surface by intermediates produced during degradation process and it leads to the lower adsorption of MB molecules in the catalytic surface ,. In addition, the loss of catalyst during the catalytic trials results to slight declination of degradation efficiency.…”

Preparation of Er3+:Y3Al5O12/WO3-KNbO3 composite and application in treatment of methamphetamine under ultrasonic irradiation

“…Recently, extensive attention has been gained to the application of sonocatalytic degradation as a novel AOPs for wastewater treatment due to its high efficiency to degrade organic pollutants, easy operation, strong penetrability, cleanness and low-cost [15][16][17]. The mechanism on ultrasonic degradation of organic pollutants can be explained based on the ultrasonic cavitation effect happened in water medium, which leads to the sonoluminescence and "hot spot" [18][19][20][21][22][23].…”