Use Of Ultrasonic Irradiation Research Articles

Bioengineered synthesis of phytochemical-adorned green silver oxide (Ag2O) nanoparticles via Mentha pulegium and Ficus carica extracts with high antioxidant, antibacterial, and antifungal activities

Silver oxide nanoparticles have various biomedical and pharmaceutical applications. However, conventional nanofabrication of Ag2O is associated with the use of toxic chemicals and organic solvents. To circumvent this hurdle, herein silver oxide quantum dots (Ag2O-QDs) were synthesized quickly (3 min) via the use of ultrasonic irradiation and plant-extract. Additionally, due to ultrasonic irradiation's effect on cell-wall destruction and augmentation of extraction efficiency, ultrasonic was also used in the preparation of Mentha pulegium and Ficus carica extracts (10 min, r.t) as natural eco-friendly reducing/capping agents. The UV–Vis result indicated a broad absorption peak at 400–500 nm. TEM/SEM analysis showed that ultrasound introduced a uniform spherical particle and significantly reduced particle size compared to the conventional heating method (∼ 9 nm vs. ∼ 100 nm). Silver and oxygen elements were found in the bio-synthesized Ag2O by EDS. The FTIR and phenol/flavonoid tests revealed the presence of phenol and flavonoid associated with the nanoparticles. Moreover, nanoparticles exhibited antioxidant/antibacterial/antifungal activities. The MIC and MBC results showed the Ag2O QDs synthesized with M. pulegium extract have the highest antibacterial activity against E. coli (MBC = MIC:15.6 ppm), which were significantly different from uncoated nanoparticles (MBC = MIC:500 ppm). The data reflects the role of phyto-synthesized Ag2O-QDs using ultrasonic-irradiation to develop versatile and green biomedical products.

Synergistic effects of ultrasonic irradiation and α-Fe2O3 nanoparticles on the viscosity and thermal properties of an asphaltenic crude oil and their application to in-situ combustion EOR

In this work, the effects of ultrasonic irradiation assisted by α-Fe2O3 nanoparticles (NPs) on the evolution of viscosity and thermal properties of crude oil are evaluated. A viscous crude oil with a high amount of asphaltene (∼20% by mass) was used for ultrasonication over different exposure times and nanoparticle concentrations. The viscosity of the oil before and after ultrasonic irradiation was measured with and without nanoparticles. Experimental results indicated that the viscosity of irradiated oil containing nanoparticles at optimum conditions was lower than the viscosity of nanoparticle-free irradiated oil. The thermal behavior of the irradiated crude oil mixed with nanoparticles at optimum conditions was examined using the TGA/DTA methods. The results showed a non-complementary effect of ultrasonic irradiation and nanoparticles on the weight loss and the amount of residual oil at both the end of the pyrolysis and oxidation stages, representing that addition of the α-Fe2O3 NPs to the crude oil and the ultrasonication of the crude oil work in the opposite direction. Based on the TG/DTA data, the kinetic parameters of the pyrolysis and oxidation reactions were estimated. It was found that the simultaneous use of ultrasonic irradiation and nanoparticles sharply decreased the activation energy of the oxidation reactions, but had almost no effect on the activation energy of the pyrolysis reactions. The results of this paper provide an insight into the effectiveness of in-situ combustion enhanced oil recovery, which depends on viscosity reduction and the rate at which heat is generated.

Nanostructured materials via green sonochemical routes – Sustainability aspects

The production of environmentally friendly nanostructured materials with well-defined properties is a major challenge. Characteristics of the nanomaterials such as dimensionality, size and morphology strongly affect their performance in various applications. Additionally, sustainability considerations require an acceptable level of efficiency while being economically feasible and environmentally benign. The use of ultrasonic irradiation (UI) is a green and powerful technology, which can be applied for the synthesis of a variety of nanostructured materials. This review critically discusses the progress made in the fabrication of environmentally benign engineered nanomaterials with various dimensionalities (i.e., zero, one, two, or three dimensions) assisted by UI. The evolution and current status in this area are further illustrated using a scientometric approach. Application of UI for the synthesis of nanostructured materials has been also assessed according to the main sustainability pillars including the performance and environmental compatibility, as well as the relevant economic and social considerations. The outlook as well as recommendations for future research has been also provided and discussed towards the promotion of sustainable nanomaterials synthesis and application in various fields.

Sonosynthesis of Spiro-Oxindoles Using Crosslinked Sulfonated Polyacrylamide Tethered to nano-Fe3O4 as High Performance Catalyst

Crosslinked sulfonated polyacrylamide (Cross-PAA-SO3H) tethered to nano-Fe3O4 as a superior heterogeneous solid acid catalyst has been used for the preparation of eight spiro-oxindoles by reactions of phenylhydrazine or hydrazine hydrate, isatins, ketoesters and naphthylamine or 2-naphthol under ultrasonic irradiations. The present catalytic procedure is extensible to a wide diversity of substrates for the synthesis of a variety-oriented library of oxindoles. The structures of the prepared oxindoles were fully characterized by 1H and 13C NMR spectra, FT-IR spectra, and elemental analysis. Experimental simplicity, wide range of products, excellent yields in short reaction times, reusability of the catalyst, low catalyst loading and use of ultrasonic irradiation, are some of the substantial features of this method. The feasibility of performing one-pot multi-component synthesis under ultrasonic irradiation with a heterogeneous catalyst could improve the reactions rates and shorten the reactions times.

Ultrasound assisted preparation and characterization of Ag supported on ZnO nanoparticles for visible light degradation of methylene blue dye

The present work reports sonochemical preparation of zinc oxide (ZnO) and silver decorated ZnO (9wt%) with the use of zinc acetate, silver nitrate and sodium carbonate as precursors in 60min duration. The resulted ZnO and silver decorated ZnO nanoparticles were characterized with SEM, FE-SEM, FTIR, XRD and UV–Vis techniques. XRD analysis reveals hexagonal quartzite crystalline phase of ZnO with highest purity. The doping of silver differs the ionic radii of the elements and that produces the strain in Ag-ZnO nanocomposites. The average crystallite size of ZnO and Ag-ZnO estimated to be 17.53 and 18.73nm, respectively with the use of XRD analysis. The lattice parameters, crystallite size and unit cell volume was observed to be increased with the loading of Ag on ZnO nanoparticles during its preparation with the aid of ultrasonic irradiations. The observed lesser size of nanoparticles and nanocomposites is due to the use of ultrasonic irradiations. Photocatalytic properties of ZnO and Ag-ZnO (doped) nanocomposite was examined for the degradation of methylene blue (MB) dye in aqueous solution under solar light irradiations. Influence of the initial dye concentration, catalyst loading, pH, and temperature on the degradation of MB dye was investigated and optimized conditions were obtained. Furthermore, a relative study of photocatalytic properties of ZnO and Silver doped ZnO nanocomposites prepared by conventional and sonication method was accomplished and the results were discussed. A maximum degradation of MB dyes was achieved (~96.2%) under optimized conditions for Ag doped ZnO nanocomposite prepared by ultrasound assisted method.

Comparison between Conventional and Nonconventional Methods for the Synthesis of Some 2-Oxazolidinone Derivatives and Preliminary Investigation of Their Inhibitory Activity Against Certain Protein Kinases

A series of propargyl and allyl carbamates were prepared directly from propargyl and allyl alcohols and phenyl or cyclohexyl isocyanate or indirectly by generating the isocyanates in situ from the corresponding Cbz-protected amines. The obtained carbamates underwent intramolecular nucleophilic cyclization in presence of cesium hydroxide monohydrate as a base catalyst under conventional and ultrasonic irradiation conditions to give the corresponding substituted 4-(benzylidene)methylidene-2-oxazolidinones in good to excellent yields. The use of ultrasonic irradiation provided remarkably improved yield of the cyclization products and significant shortening of the reaction time. In some cases the reaction was highly stereoselective, and (Z)-4-benzylideneoxazolidinones were formed as a single stereoisomer. A series of biological tests were performed to evaluate the inhibitory potential of all synthesized compounds against some protein kinases.

Scaled-up biodiesel synthesis from Chinese Tallow Kernel oil catalyzed by Burkholderia cepacia lipase through ultrasonic assisted technology: A non-edible and alternative source of bio energy.

In East Asia, for thousands of years, the fruit of Chinese tallow tree (Sapium sebiferum) has been used for multiple purposes because of its chemical composition; the presence of high amounts of lipids is remarkable, showing potential to be used as substrate for biodiesel synthesis. Previously have been reported the use of alkaline and enzymatic catalysts, microwave technology and the use of ionic liquids as co-solvents with the lipids of this tree species to produce biodiesel. This study shows the results of the use of Burkholderia cepacia lipase as enzymatic catalyst for transesterification of Chinese Tallow Kernel oil (CTK), extracted from the fruit of Chinese tallow tree, into biodiesel, with the use of ultrasonic assisted technology and without the usage of solvents. The optimal operational parameters were determined and the reactions were developed in a batch reactor with the use of ultrasonic irradiation and emulsification to enhance the mass transfer. The scaled-up experiments, in an especially designed 3 L capacity reactor, showed promising results, obtaining 55.20% biodiesel and a kinematic viscosity of 10.31 mm2.s-1 in only 4 h, in comparison with previously published (in vitro) methods. The valorization of this non-edible source of oil represents an opportunity to use as an alternative source for bioenergy and also to tackle the uncontrolled expansion of this oleaginous tree species in some ecologically fragile ecosystems.

Method of localized removal of cells using a bolt-clamped Langevin transducer with an ultrasonic horn.

Cell isolation by eliminating undesirable cell aggregations or colonies with low activity is essential to improve cell culture efficiency. Moreover, when creating tissues from induced pluripotent stem cells, residual undifferentiated cells must be removed to prevent tumor formation in vivo. Here, we evaluated the use of ultrasonic irradiation, which can apply energy locally without contact, and proposed a method to eliminate cells in a small area of culture by ultrasonic irradiation from a Langevin transducer. We constructed a device that incorporated a bolt-clamped 19.84kHz Langevin transducer with an ultrasonic horn and determined the optimal conditions for stable elimination of cells in small areas of a 35-mm culture dish. The optimal conditions were as follows: number of cycles=400, clearance distance=1mm, volume of medium=4mL, and distance from the center of culture surface=0mm. The mean cell elimination area under these conditions was 0.097 mm2. We also evaluated the viability of neighboring cells after ultrasonic irradiation by fluorescent staining and found that most cells around the elimination area survived. These findings suggest that the proposed method has potential for localized elimination of cells without the need for contact with the cell surface.

Synthesis of benzamides through direct condensation of carboxylic acids and amines in the presence of diatomite earth@IL/ZrCl4 under ultrasonic irradiation

A green, rapid, mild and highly efficient pathway for the preparation of benzamide derivatives is reported. The reaction was performed through direct condensation of benzoic acids and amines under ultrasonic irradiation in the presence of Lewis acidic ionic liquid immobilized on diatomite earth (diatomite earth@IL/ZrCl4). A new, highly efficient and green solid acid catalyst was easily prepared via a two-step procedure and used as an effective reusable catalyst. The prepared catalyst provides active sites for the synthesis of benzamides. The advantages of this method are the use of a superior and recoverable catalyst, low reaction times, simple procedure, high-yielding and eco-friendly process and use of ultrasonic irradiation as a green and powerful technology. Since benzamides are used widely in the pharmaceutical, paper and plastic industries, and also as an intermediate product in the synthesis of therapeutic agents, the presented new synthetic methods for this type of compounds can be of considerable importance.

Features of two- and multicomponent heterocyclization reactions involving 3,4-disubstituted 5-aminopyrazoles and alkyl pyruvates

Three-component heterocyclizations of pyruvic acids and their esters with 5-aminopyrazoles and aromatic aldehydes, in addition to the sequential versions of these reactions, under different activating conditions were studied. Under conventional heating, pyrazolopyrimidine derivatives containing a hydroxyl group in the 6-position were formed in both two- and three-component treatments. Whereas the application of an inert atmosphere did not influence the outcome of these reactions, the use of ultrasonic irradiation led to the formation of 7-hydroxy-tetrahydropyrazolopyrimidines in multi-component reactions and 6-hydroxy-dihydropyrazolopyrimidines in the case of a step-by-step approach. The products of the latter treatment were further transformed into heteroaromatized 6-hydroxy-pyrazolopyrimidines by conventional heating.

Effect of ultrasound on dyeing of wool fabric with acid dye

Wool fiber strength and handle is damaged by holding for prolonged periods at normal dyeing temperatures (98 °C). Lower dyeing temperatures can be employed to color wool whilst reducing damage caused to the fiber. However, these lower temperature dyeing processes often have a long dyeing time and/or require the addition of chemicals to achieve adequate dye exhaustion and migration. The use of ultrasonic irradiation was used to reduce dyeing times and temperatures whilst increasing dye migration and fastness. It has used 30 kHz frequency level, effective power of 120 and 350 W heating power in ultrasonic machine. In this work, wool dyeing was carried out on single jersey knitted fabric using an acid dye with and without ultrasonic irradiation at 60, 70, and 80 °C. Dye exhaustion was measured using UV/visible absorbance of the dye bath before and during the dyeing cycle. For the measurement of nodal/anti-nodal point of energy, at 60, 70, and 80 °C dyeing was done in open bath of ultrasonic machine with and without sonication at high liquor ratio. To compare the dye uptake (%) at high/conventional process, sample was dyed at 95 °C. Optical and scanning electron microscopy were used to measure the diameter and surface changes of the fiber, respectively. Wash and rub fastness was measured on the dyed fabrics after rinsing and drying. Ultrasonic irradiation during the dyeing of wool caused an increase in the dye exhaustion rate for acid dye. This change in rate is believed to have been caused by a reduction in the viscous boundary layer of liquor surrounding the fiber present in an ultrasonic irradiated environment. An increased dye migration due to cuticle cracking and fiber swelling was not deemed to have occurred as wet fiber diameter was not changed by submersion in the dye liquor in the presence of ultrasound and no surface cracking was evident in scanning electron microscopy images. Some cuticle structure changes occurred with turning up or ripping off of the cuticle tips evident. Both wash and rub fastness were improved for ultrasonically dyed fiber with dyeing temperatures of 70 and 80 °C being suitable for the low-temperature dyeing of wool.

Ultrasound-assisted surface treatment of ZrO2 with BSA and incorporating in PVC to improve the properties of the obtained nanocomposites: Fabrication and characterization

This paper describes the preparation of poly(vinyl chloride) (PVC) nanocomposites (NCs) reinforced with modified zirconia (ZrO2) nanoparticles (NPs). The ZrO2 NPs were defined as efficient filler for PVC NCs. For achieving the best dispersion and improvement of properties, the surface of ZrO2 NPs was modified by Bovine Serum Albumin (BSA). Carboxylic acids and amines are important functional groups of BSA which handle the grafting BSA on the surface of ZrO2 NPs. The PVC/ZrO2-BSA NCs were fabricated by incorporation of various amounts of the ZrO2-BSA NPs (3, 6 and 9wt%) into PVC matrix. All the above processes were accomplished by ultrasonication asa green and environmentally-friendly method. Also, the magnetic and mechanical stirrer was used for the preparation of samples but the results are not suitable and the aggregation was observed which indicated the use of ultrasonic irradiation is the best method for the preparation of NC. The products were characterized by Fourier transform infrared spectroscopy, Transmission electron microscopy, Field emission scanning electron microscopy, X-ray diffraction, Thermogravimetric analysis, Ultraviolet–visible spectroscopy, photoluminescence spectroscopy, energy dispersive X-ray spectroscopy, wettability, and mechanical tests. The achieved PVC/ZrO2-BSA NCs showed high thermal stability, good mechanical, optical and wettability properties compared to the pure PVC. In addition, among the obtained NCs, the PVC/ZrO2-BSA NC 6wt% showed the best improvement.

Ultrasound-assisted chemoenzymatic epoxidation of soybean oil by using lipase as biocatalyst

The present work reports the use of ultrasonic irradiation for enhancing lipase catalyzed epoxidation of soybean oil. Higher degree of unsaturated fatty acids, present in the soybean oil was converted to epoxidized soybean oil by using an immobilized lipase, Candida antarctica (Novozym 435). The effects of various parameters on the relative percentage conversion of the double bond to oxirane oxygen were investigated and the optimum conditions were established. The parameters studied were temperature, hydrogen peroxide to ethylenic unsaturation mole ratio, stirring speed, solvent ratio, catalyst loading, ultrasound frequency, ultrasound input power and duty cycle. The main objective of this work was to intensify chemoenzymatic epoxidation of the soybean oil by using ultrasound, to reduce the time required for epoxidation. Epoxidation of the soybean oil was achieved under mild reaction conditions by indirect ultrasonic irradiations (using ultrasonic bath). The relative percentage conversion to oxirane oxygen of 91.22% was achieved within 5h. The lipase was remarkably stable under optimized reaction conditions, later was recovered and reused six times to produce epoxidized soybean oil (ESO).

Ultrasound-promoted copper-catalyzed synthesis of bis-arylselanyl chrysin derivatives with boosted antioxidant and anticancer activities

Herein we report the use of ultrasonic irradiation (US) in the synthesis of six new semi-synthetic selenium-containing chrysin derivatives by a simple and effective methodology utilizing CuI as catalyst, in good to excellent yields (60–89%). It was observed that US accelerates the reaction compared to conventional heating with excellent selectivity for diselenylated products. Compounds were tested for their antioxidant and anticancer activities in vitro and it was observed that the presence of selenium in the A-ring of chrysin enhanced both antioxidant and anticancer properties. Semi-synthetic 6,8-bis(o-tolylselanyl)-chrysin 3b has the best radical scavenging activity of DPPH (Imax: 39.79µM) and ABTS+ (IC50: 6.5µM) radicals. Similarly, in the Reactive Species (RS) assay, 3b showed high antioxidant activity in mice cortex (IC50: 5.67µM), whereas 6,8-bis(p-anisoylselanyl)-chrysin 3c was the more active in the hippocampus (IC50: 5.63µM). The Se-chrysins were effective in prevention of lipid peroxidation, highlighting 6,8-bis(p-fluorophenylselanyl)-chrysin 3d in cortex (IC50: 0.54µM) and 3b in hippocampus (IC50: 0.27µM). In addition, 3d was effective in inhibiting human lung adenocarcinoma (A549) cells growth, with a IC50 of 19.9µM after 72h of treatment, while 6,8-bis(p-anisoylselanyl)-chrysin 3c presented the higher antiproliferative activity after 48h of treatment (IC50 of 41.4µM).

Ultrasonic promoted synthesis of novel s-triazine-Schiff base derivatives; molecular structure, spectroscopic studies and their preliminary anti-proliferative activities

Novel series of s-triazine-Schiff base derivatives were synthesized employing ultrasonic irradiation and characterized by NMR (1H and 13C), FT-IR, and elemental analysis. The use of ultrasonic irradiation has allowed the preparation of the target products with better yields in shorter reaction time and excellent purities compared to the conventional heating. X-ray single crystal diffraction experiments verified the molecular structure of four from the new prepared s-triaizne-Schiff base derivatives. The molecular structures of the studied compounds are computerized using DFT/B3LYP method. The effects of substituent at the triazine and phenyl ring on the electronic and spectroscopic properties of the studied compounds were also investigated. The natural atomic charges showed that pipridino-s-triazine derivatives are richer in electrons than those having morpholino derivatives. The anti-proliferative effects for the prepared compounds were tested against three different cancer cell lines.

Ultrasound assisted electrodeposition of Zn and Zn-TiO2 coatings

Pristine Zn and Zn-TiO2 coatings were galvanostatically electrodeposited on steel substrates from additive-free chloride-based plating baths under silent and ultrasonic conditions. An ultrasonic bath-setup (38kHz) was used as a sonoelectrochemical system. The influence of ultrasonic irradiation on the layer properties was investigated using different combinations of ultrasonic power and current density. In general, the use of ultrasonic irradiation for assisting the electrodeposition of pristine Zn and Zn-TiO2 layers does have impact on the morphological and structural properties of the electrodeposits. The use of ultrasonic irradiation for dispersing particles during the electro-codeposition process was shown to be beneficial provided the use of suitable ultrasonic and deposition parameters. The incorporation of particles into the metallic matrix was confirmed with glow discharge optical emission spectroscopy investigations and focused-ion-beam-assisted cross-sectional analysis. The presence of TiO2 agglomerates having smaller sizes as well as a better distribution in the metallic matrix was observed for the combination of ultrasonic agitation and high-speed electrodeposition. Pyramidal textures corresponding to the (101), (102), (103) and (112) planes were found characteristic for Zn layers having incorporated TiO2 particles. One aspect of using ultrasonic agitation during electroplating is that Zn layers might also be prone to cavitation/erosion phenomena. Nevertheless, this effect can be controlled by adjusting the ultrasonic power as well as the ultrasonic irradiation time.

Comparison between Conventional and Ultrasonic Preparation of Chitosan from Shrimp Shells Waste

Chitosan is a natural biopolymer derived by deacetylation of chitin from the two main sources of crustaceans, shrimp and crabs. Chitosan, which is soluble in acidic solutions, is used in many applications (biomedical/pharmaceutical, water engineering, food, cosmetics). There have been many researchers who have developed a process of deacetylation of chitin from shrimp shells waste by thermochemical or enzymatic methods. However, application of ultrasonic irradiation for chitin deacetylation has received little attention. In this work, the deacetylation of chitin with concentrated sodium hydroxide was performed using ultrasound irradiation (80 W, 42 kHz). The reaction time and degree of deacetylation were compared with conventional process. Results showed that under the same condition, the degree of deacetylation was similar. However, the use of ultrasonic irradiation decreased the reaction time, showing that this method may be a promising alternative method to the conventional method.

초음파를 이용한 레드머드로부터 유가금속 회수에 관한 연구

The red mud generated from the Bayer alumina production process seriously threatens the environment and human safety. Therefore, the reduction and recycling of red mud is an urgent topic in the aluminum industry. In this study, the effects of four parameters, ultrasound power, reaction temperature, time, and acid concentration, on the leaching of Fe, Al from red mud was investigated. The major parameters influencing the metal recovery efficiency from red mud were ultrasound power and reaction temperature. The use of ultrasonic irradiation resulted in 1.72 and 1.28 times higher recovery efficiency for Fe and Al, respectively. The proper conditions for the recovery of the metal components present in the red mud is the ultrasound intensity (150 W), sulfuric acid concentration (4-6N), reaction temperature (70 ℃), and reaction time (2 hours), etc.

Methanol conversion to DME as a blue fuel: The beneficial use of ultrasonic irradiation for the preparation of CuO/H-MOR nanocatalyst

Methanol conversion to DME was investigated over CuO/H-MOR nanocatalyst prepared by precipitation and/or by precipitation flowed by ultrasonic irradiation methods. BET, XRD, SEM, NH3-TPD and H2-TPR techniques were used to characterize nanocatalysts. The effective ultrasonication factors encountered during carrying out the dehydration of methanol on CuO/H-MOR zeolite catalysts to produce dimethylether are studied in the present work. These factors include: the type of ultrasonication media, the ultrasonication time, and the fixed weight of the solid catalyst per the volume of the ultrasonication liquid media (Wcatalyst/Vliquid ratio). XRD showed that structure of H-MOR is not damaged even after it is loaded with CuO nanoparticles or with ultrasonication. H2-TPR profiles indicated that reducibility of sonicated CuO/H-MOR nanocatalyst is higher than non-sonicated catalyst. It is found that employing ultrasound energy for 60 min has the highest influence on the surface properties of nanocatalyst and its catalytic performance (activity and stability) of CuO/H-MOR catalyst. Surface morphology (SEM) of the sonicated CuO/H-MOR catalysts have clarified that methanol by itself used as an ultrasonication medium gives the best results concerning the homogeneity of particle sizes compared to the non-sonicated catalyst, where large agglomerates and non-homogeneous clusters appeared. Water used as a sonication medium showed many large agglomerates in addition to some smaller particles resulted in low catalytic activity. The different alcohols and (Wcatalyst/Vliquid) ratio were examined to give precise correlation with the catalytic activity of the sonicated CuO/H-MOR zeolite catalyst. These findings certified that ultrasonication has a deep effect on the surface morphology and hence on the catalytic behavior of the dehydration of methanol to DME. NH3-TPD shows that ultrasound irradiation has enhanced the acidity of CuO/H-MOR catalyst and hence it's catalytic performance for DME formation.

Ultrasound-Assisted Oxidative Desulfurization of Diesel Fuel in H<sub>2</sub>O<sub>2</sub>/Heteropoly Acid/Solvent System

Ultrasound-assisted oxidative desulfurization (UAODS) of diesel fuel in H2O2/Heteropoly acid/Solvent systems, was investigated. Effects of solvent, catalyst, ultrasound and reaction temperature on the oxidation desulfurization of diesel fuel were investigated. When MPA/oil was 2%wt, methanol/diesel fuel was 20%wt, ultrasound power was 400 W and ultrasound time was 10 min, the sulfur content of diesel fuel was decreased from 211 ppm to 19 ppm. The use of ultrasonic irradiation in H2O2/Heteropoly acid/Solvent system significantly improved the efficiency of the oxidation reaction, and solvent was helpful to make the oxidative reaction happen in the same one phase.