Note: US, Ultrasound; PS, peroxydisulfate; PS, peroxymonosulfate. The sonication-involved processes in water matrices.
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•The generation of •OH radicals by ultrasound is insufficient to ...cause significant antibiotics cleavage.•Sonication improves mass transfer and oxidation with Fenton reagents, S2O82−, HSO5− and O3.•Sonophotocatalysis remarkably enhances antibiotics mineralization and detoxification.
Antibiotic residues in water are general health and environmental risks due to the antibiotic-resistance phenomenon. Sonication has been included among the advanced oxidation processes (AOPs) used to remove recalcitrant contaminants in aquatic environments. Sonochemical processes have shown substantial advantages, including cleanliness, safety, energy savings and either negligible or no secondary pollution. This review provides a wide overview of the different protocols and degradation mechanisms for antibiotics that either use sonication alone or in hybrid processes, such as sonication with catalysts, Fenton and Fenton-like processes, photolysis, ozonation, etc.
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•Electric discharge plasma in liquid media via hydrodynamic cavitation bubbles.•Fast degradation of metronidazole in 15 min without addition of chemical reagents.•Generation of UV ...light and reactive oxidant species under strong physical cavitation.•Assessment of plasma discharge stability in drinking water matrix.
In this study, a novel hydrodynamic cavitation unit combined with a glow plasma discharge system (HC-GPD) was proposed for the degradation of pharmaceutical compounds in drinking water. Metronidazole (MNZ), a commonly used broad-spectrum antibiotic, was selected to demonstrate the potential of the proposed system. Cavitation bubbles generated by hydrodynamic cavitation (HC) can provide a pathway for charge conduction during glow plasma discharge (GPD). The synergistic effect between HC and GPD promotes the production of hydroxyl radicals, emission of UV light, and shock waves for MNZ degradation. Sonochemical dosimetry provided information on the enhanced formation of hydroxyl radicals during glow plasma discharge compared to hydrodynamic cavitation alone. Experimental results showed a MNZ degradation of 14% in 15 min for the HC alone (solution initially containing 300 × 10−6 mol L−1 MNZ). In experiments with the HC-GPD system, MNZ degradation of 90% in 15 min was detected. No significant differences were observed in MNZ degradation in acidic and alkaline solutions. MNZ degradation was also studied in the presence of inorganic anions. Experimental results showed that the system is suitable for the treatment of solutions with conductivity up to 1500 × 10−6 S cm−1. The results of sonochemical dosimetry showed the formation of oxidant species of 0.15 × 10−3 mol H2O2 L−1 in the HC system after 15 min. For the HC-GPD system, the concentration of oxidant species after 15 min reached 13 × 10−3 molH2O2L−1. Based on these results, the potential of combining HC and GPD systems for water treatment was demonstrated. The present work provided useful information on the synergistic effect between hydrodynamic cavitation and glow plasma discharge and their application for the degradation of antibiotics in drinking water.
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•Water disinfection by simultaneous treatment with hydrodynamic cavitation and plasma discharge.•Decomposition of organic pollutants in water under hydrodynamic cavitation and ...plasma.•Easily scalable hybrid technology combining cavitation and plasma.•Intense generation of radicals, UV light, shock waves and charged particles.•Prolonged oxidation takes place in the solution/suspension after the end of the treatment.
Over the last two decades, the scientific community and industry have made huge efforts to develop environmental protection technologies. In particular, the scarcity of drinking water has prompted the investigation of several physico-chemical treatments, and synergistic effects have been observed in hyphenated techniques. Herein, we report the first example of water treatment under simultaneous hydrodynamic cavitation and plasma discharge with the intense generation of radicals, UV light, shock waves and charged particles. This highly reactive environment is well suited to the bulk treatment of polluted water (i.e. E. coli disinfection and organic pollutant degradation). We have developed a new prototype and have efficiently applied this hybrid technology to water disinfection and the complete degradation of methanol in water with the aim of demonstrating its scalability. We have analyzed the mechanisms of water disinfection under the abovementioned conditions and verified them by measuring cavitation noise spectra and plasma emission spectra. We have also used the degradation of textile dyes and methanol solutions as an indicator for the formation of radicals.
•We studied the sol-gel method for the titanium dioxide nanoparticles synthesis from titanyl sulphate.•We studied the synthesis of titanium dioxide and zinc oxide nanoparticles via sol-gel ...method.•The nanoparticles were synthesized near textile fibers and deposited on them in the same process via ultrasound.•Coated fabrics showed a suppression level of E. coli of more than 99.99% and the antibacterial activity of more than 1.8.•Such textiles can be used to prevent the spread of the nosocomial and other infections.
To prevent possible spread of nosocomial infections – HAI (Healthcare Acquired Infections) in healthcare facilities, Antibacterial textiles are developed. This carried out study has been conducted to assess the feasibility of the method of obtaining antibacterial coatings on textile materials. Specifically, the sol-gel method for synthesis of titanium dioxide nanoparticles in combination with zinc oxide nanoparticles from titanyl sulphate and zinc nitrate hexahydrate has been investigated.
During the synthesis of titanium dioxide nanoparticles in combination with the zinc oxide nanoparticles, the coated textile material showed stable antibacterial properties with a suppression level ofEscherichia coliof more than 99.99%. The method has been tested on a semi-industrial scale in roll-to-roll experimentby applying homogenous coatings at a speed of 1,5 m per minute.
•The effect of ultrasound on viscosity of oil in well conditions was investigated.•A long lasting decrease in viscosity can be obtained only by sonochemical treatment.•The use of ultrasound may ...facilitate the production of viscous hydrocarbons.
Reduction of oil viscosity is of great importance for the petroleum industry since it contributes a lot to the facilitation of pipeline transportation of oil. This study analyzes the capability of acoustic waves to decrease the viscosity of oil during its commercial production. Three types of equipment were tested: an ultrasonic emitter that is located directly in the well and affects oil during its production and two types of acoustic machines to be located at the wellhead and perform acoustic treatment after oil extraction: a setup for ultrasonic hydrodynamic treatment and a flow-through ultrasonic reactor. In our case, the two acoustic machines were rebuilt and tested in the laboratory. The viscosity of oil was measured before and after both types of acoustic treatment; and 2, 24 and 48h after ultrasonic treatment and 1 and 4h after hydrodynamic treatment in order to estimate the constancy of viscosity reduction. The viscosity reduction achieved by acoustic waves was compared to the viscosity reduction achieved by acoustic waves jointly with solvents. It was shown, that regardless of the form of powerful acoustic impact, a long lasting decrease in viscosity can be obtained only if sonochemical treatment is used. Using sonochemical treatment based on ultrasonic hydrodynamic treatment a viscosity reduction by 72,46% was achieved. However, the reduction in viscosity by 16%, which was demonstrated using the ultrasonic downhole tool in the well without addition of chemicals, is high enough to facilitate the production of viscous hydrocarbons.
•The use of 3 different types of waveguide systems for activation of ASFC reagents was investigated.•Ultrasound enables to reactivate the alumosilicic flocculant-coagulant.•In scaled up reactors the ...choice of the equipment type affects the stability of the achieved effect.
Acoustic fields formed during operation of ultrasonic reactors with waveguides of following types: rod-type, cylindrical with rectangular protrusions and tubular were calculated and measured. The influence of distribution of acoustic fields arising from the operation of waveguide systems of three different types on the efficiency of ultrasonic activation of alumosilicic flocculant-coagulant and magnetite intended for water purification was investigated. It was shown that regardless of the equipment used on an industrial scale it is possible to reactivate the alumosilicic flocculant-coagulant even after the shelf life period of it passed, however in case of activation of magnetite the use of a bigger reactor in inefficient.
In case of industrial scale processes, the choice of the correct reactor design is of significant importance, since it allows to reduce the required processing time, and, as a result, the energy consumption of the processes. The advantages of tubular waveguide systems include the possibility of processing large volumes of liquid. The high efficiency and uniformity of the excited ultrasonic fields can lead to reduction of operating costs. In case of smaller flows, the waveguide system with rectangular protrusions allowed to obtain better results.
Our work illustrates the dependence of the success of a specific method on the choice of the waveguide and the size of the reactor during upscale.
•A sonochemical method is developed to enhance oil recovery from horizontal oil wells.•Ultrasound can enhance the effect of chemicals used to improve the performance of wells.•The method increases ...the permeability of the wellbore perforation zone and reduces blockages.•Field tests of the sonochemical method of EOR in vertical and horizontal wells have shown a significant improvement in oil production.
Oil production from wells reduces with time and the well becomes uneconomic unless enhanced oil recovery (EOR) methods are applied. There are a number of methods currently available and each has specific advantages and disadvantages depending on conditions. Currently there is a big demand for new or improved technologies in this field, the hope is that these might also be applicable to wells which have already been the subject of EOR. The sonochemical method of EOR is one of the most promising methods and is important in that it can also be applied for the treatment of horizontal wells. The present article reports the theoretical background of the developed sonochemical technology for EOR in horizontal wells; describes the requirements to the equipment needed to embody the technology. The results of the first field tests of the technology are reported.
•A down hole method for ultrasonic treatment is developed to enhance oil recovery on failing oil wells.•The method increases the permeability of the bottom hole zone and reduces blockages.•The method ...is simple, environmentally safe and is successful in up to 85% of cases.•The effect due to ultrasonic treatment lasts for 3–12months.
A new method for the ultrasonic enhancement of oil recovery from failing wells is described. The technology involves lowering a source of power ultrasound to the bottom of the well either for a short treatment before removal or as a permanent placement for intermittent use. In wells where the permeability is above 20mD and the porosity is greater than 15% ultrasonic treatment can increase oil production by up to 50% and in some cases even more. For wells of lower permeability and porosity ultrasonic treatment alone is less successful but high production rates can be achieved when ultrasound is applied in conjunction with chemicals. An average productivity increase of nearly 3 fold can be achieved for this type of production well using the combined ultrasound with chemical treatment technology.
This paper reports the results of the large-scale field testing of composite materials with antibacterial properties in a tropical climate. The composite materials, based on a cotton fabric with a ...coating of metal oxide nanoparticles (TiO2 and/or ZnO), were produced using high-power ultrasonic treatment. The antibacterial properties of the materials were studied in laboratory tests on solid and liquid nutrient media using bacteria of different taxonomic groups (Escherichia coli, Chromobacterium violaceum, Pseudomonas chlororaphis). On solid media, the coatings were able to achieve a >50% decrease in the number of bacteria. The field tests were carried out in a tropical climate, at the Climate test station “Hoa Lac” (Hanoi city, Vietnam). The composite materials demonstrated long-term antibacterial activity in the tropical climate: the number of microorganisms remained within the range of 1–3% in comparison with the control sample for the duration of the experiment (3 months). Ten of the microorganisms that most frequently occurred on the surface of the coated textiles were identified. The bacteria were harmless, while the fungi were pathogenic and contributed to fabric deterioration. Tensile strength deterioration was also studied, with the fabrics coated with metal oxides demonstrating a better preservation of their mechanical characteristics over time, (there was a 42% tensile strength decrease for the reference non-coated sample and a 21% decrease for the sample with a ZnO + CTAB coating).
Flexible materials, such as fabric, paper and plastic, with nanoscale particles that possess antimicrobial properties have a significant potential for the use in the healthcare sector and many other ...areas. The development of new antimicrobial coating formulations is an urgent topic, as such materials could reduce the risk of infection in hospitals and everyday life. To select the optimal composition, a comprehensive analysis that takes into account all the advantages and disadvantages in each specific case must be performed. In this study, we obtained an antimicrobial textile with a 100% suppression of E. coli on its surface. These CeO2 nanocoatings exhibit low toxicity, are easy to manufacture and have a high level of antimicrobial properties even at very low CeO2 concentrations. High-power ultrasonic treatment was used to coat the surface of cotton fabric with CeO2 nanoparticles.
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