Jean-Louis Luche and the Interpretation of Sonochemical Reaction Mechanisms
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Understanding and Optimising Sonication Conditions for Crystallisation Processes
Buenos Aires – 5 to 9 September, 2016 Acoustics for the 21st Century… PROCEEDINGS of the 22nd International Congress on Acoustics Sonochemistry and Sonoprocessing: Paper ICA2016-202 Understanding and optimising sonication conditions for crystallisation processes Nnamdi Ugochukwu(a), Madeleine Bussemaker(b), Judy Lee(c) (a)-(c) Chemical and Process Engineering University of Surrey, United Kingdom, [email protected] Abstract Crystallisation is a common technique adopted by many industries for separation and purification operations but it can suffer from unpredictable nucleation rates and inconsistencies in product qualities. To remediate these problems, ultrasound has been used to facilitate and control nucleation of crystals (sonocrystallisation), resulting in a more consistent and narrower size distribution of product. However, the mechanism behind sonocrystallization process is contentious and often reported is the continuous sonication of the system, which causes issues such as heating, probe surface erosion and cost of additional input energy. This study examines the influence of cavitation activity and different modes of pulse sonication on the crystallisation process. The results show a close association between cavitation activity, quantified in terms of sonoluminescence intensity, and the minimum crystal size obtained. In addition, the initial short sonication time 5 seconds proves to be effective for sonocrystallisation, showing results that are comparable to systems undergone 90seconds of sonication. Keywords: Acoustic cavitation, sonocrystallisation, sonoluminescence. 22nd International Congress on Acoustics, ICA 2016 Buenos Aires – 5 to 9 September, 2016 Acoustics for the 21st Century… Understanding and optimising sonication conditions for crystallisation processes 1 Introduction Antisolvent crystallisation is a common technique adopted by many industries for separation or purification operations[1]. -
Ultrasound Induced Cavitation and Resonance Amplification Using Adaptive Feedback Control System
Master's Thesis Electrical Engineering Ultrasound induced cavitation and resonance amplification using adaptive feedback Control System Vipul. Vijigiri Taraka Rama Krishna Pamidi This thesis is presented as part of Degree of Master of Science in Electrical Engineering with Emphasis on Signal Processing Blekinge Institute of Technology (BTH) September 2014 Blekinge Institute of Technology, Sweden School of Engineering Department of Electrical Engineering (AET) Supervisor: Dr. Torbjörn Löfqvist, PhD, LTU Co- Supervisor: Dr. Örjan Johansson, PhD, LTU Shadow Supervisor/Examiner: Dr. Sven Johansson, PhD, BTH Ultrasound induced cavitation and resonance amplification using adaptive feedback Control System Master`s thesis Vipul, Taraka, 2014 Performed in Electrical Engineering, EISlab, Dep’t of Computer Science, Electrical and Space Engineering, Acoustics Lab, dep’t of Acoustics at Lulea University of Technology ii | Page This thesis is submitted to the Department of Applied signal processing at Blekinge Institute of Technology in partial fulfilment of the requirements for the degree of Master of Science in Electrical Engineering with emphasis on Signal Processing. Contact Information: Authors: Vipul Vijigiri Taraka Rama Krishna Pamidi Dept. of Applied signal processing Blekinge Institute of Technology (BTH), Sweden E-mail: [email protected],[email protected] E-mail: [email protected], [email protected] External Advisors: Dr. Torbjörn Löfqvist Department of Computer Science, Electrical and Space Engineering Internet: www.ltu.se Luleå University of technology (LTU), Sweden Phone: +46 (0)920-491777 E-mail: [email protected] Co-Advisor: Dr. Örjan Johansson Internet: www.ltu.se Department of the built environment and natural resources- Phone: +46 (0)920-491386 -Operation, maintenance and acoustics Luleå University of technology (LTU), Sweden E-mail: [email protected] University Advisor/Examiner: Dr. -
Emulsification by Ultrasound: Relation Between Intensity and Emulsion Quality
Indian Journal of Chemical Technology Vol. 4, November 1997, pp. 277-284 Emulsification by ultrasound: Relation between intensity and emulsion quality Sukti Mujumdar, P Senthil Kumar & A B Pandit* Department of Chemical Technology, University ofMumbai, Matunga, Mumbai 400 019. Received 28 April 1997; accepted 15 September 1997 Ultrasonic emulsification of oil and water was carried out and the effect of position of the ultrasound source from the interface on emulsion quality was studied using ultrasonic bath and horn. Correlations for the effect of distance of the ultrasound source from the interface on various emulsion properties such as dispersed phase fraction, droplet diameter were developed. Large variation in the emulsion properties with small changes in the position of ultrasound source was observed and correlated with an exponential type of equation. Discrepancies in the results of heterogeneous liquid phase systems reported in the literature were attributed to the small changes in the location of ultrasound source. Severe attenuation of ultrasound intensity by the oil layer was quantitatively established using decomposition of aqueous KI solution as a model reaction. The droplet diameter was predicted using Kolmogorov eddy length model. The collapse pressure developed in cavitation was determined indirectly and compares favorably with the reported values. The highly localised nature of cavitation phenomenon is also well established as a cause for the variation in the emulsion quality. Heterogeneous liquid-liquid systems hold an cavitationI. Ultrasound as a source is the one that important place in the domain of chemical has been studied extensively and commercially engineering. The success of the above systems that exploited to a significant extent. -
24 August 2021 Aperto
AperTO - Archivio Istituzionale Open Access dell'Università di Torino Ultrasonically improved semi-hydrogenation of alkynes to (Z-)alkenes over novel lead-free Pd/Boehmite catalysts This is the author's manuscript Original Citation: Availability: This version is available http://hdl.handle.net/2318/1660710 since 2018-02-26T14:04:54Z Published version: DOI:10.1016/j.ultsonch.2016.05.019 Terms of use: Open Access Anyone can freely access the full text of works made available as "Open Access". Works made available under a Creative Commons license can be used according to the terms and conditions of said license. Use of all other works requires consent of the right holder (author or publisher) if not exempted from copyright protection by the applicable law. (Article begins on next page) 29 September 2021 This is an author version of the contribution published on: Questa è la versione dell’autore dell’opera: [Ultrasonically improved semi-hydrogenation of alkynes to (Z-)alkenes over novel lead-free Pd/Boehmite catalysts DOI: 10.1016/j.ultsonch.2016.05.019] ovvero [Zhilin Wu, Giancarlo Cravotto, Emanuela Calcio Gaudino, Agnese Giacomino, Jonathan Medlock, Werner Bonrath., Ultrasonics Sonochemistry 35 (2017) 664–672] The definitive version is available at: La versione definitiva è disponibile alla URL: [www.journals.elsevier.com] 1 Ultrasonically improved semi-hydrogenation of alkynes to (Z-)alkenes over novel lead-free Pd/Boehmite catalysts Zhilin Wua, Giancarlo Cravottoa*, Emanuela Calcio Gaudinoa, Agnese Giacominoa, Jonathan Medlockb, Werner Bonrathb. a Dipartimento di Scienza e Tecnología del Farmaco, Universty of Turin, Via P. Giuria 9, I-10125 Turin, Italy. b DSM Nutritional Products Ltd., Research and Development, P.O. -
A Review on Sonochemistry and Its Environmental Applications
acoustics Review A Review on Sonochemistry and Its Environmental Applications Ba¸sakSavun-Hekimo˘glu Institute of Marine Sciences and Management, Istanbul University, 34134 Istanbul,˙ Turkey; [email protected] Received: 10 September 2020; Accepted: 23 October 2020; Published: 25 October 2020 Abstract: Sonochemistry is a significant contributor to green science as it includes: (i) the use of less toxic compounds and environmentally safe solvents, (ii) improvement of reaction conditions and selectivity, (iii) no toxic sludge generation, (iv) reduction in the energy use for chemical transformations, (v) reusability of materials. In water and wastewater treatment, ultrasound is used as an advanced oxidation process to eliminate refractory pollutants. Ultrasound is also used as a very effective sludge pretreatment technology in wastewater treatment plants to facilitate biogas production. Moreover, sonochemical synthesis of nanoparticles has recently attracted great attention as a greener protocol. This paper presents the main applications of ultrasound in environmental remediation and protection. The study also introduces mechanism for the degradation of pollutants from water via sonication in aqueous media and the principle factors affecting the cavitational effect. Keywords: ultrasound; sonocatalysis; water treatment; sludge pretreatment; nanomaterials 1. Introduction to Sonochemistry Sonochemistry is a field that studies the enhancement of chemical reaction and mass transfer rates under various ultrasonic conditions. Ultrasound is characterized as any sound wave at frequencies above normal human ear hearing range (i.e., above 16 kHz). The mechanism causing sonochemical effects in liquids is the phenomenon of acoustic cavitation. When ultrasound waves propagate in a liquid medium, they generate a repeating pattern of compressions and rarefactions to supply energy to the liquid phase. -
1.41 Sonochemistry
1.41 Sonochemistry K. S. SUSLICK University of Illinois at Urbana-Champaign, Urbana, IL, USA 1.41.1 INTRODUCTION 731 1.41.1.1 Acoustic Cavitation 732 1.41.1.2 Microjet Formation During Cavitation at Liquid–Solid Interfaces 733 1.41.2 SONOLUMINESCENCE 734 1.41.2.1 Types of Sonoluminescence 734 1.41.2.2 Spectroscopic Probes of Cavitation Conditions 734 1.41.3 SONOCHEMISTRY 735 1.41.3.1 Homogeneous Sonochemistry: Bond Breaking and Radical Formation 735 1.41.3.2 Applications of Sonochemistry to Materials Synthesis 736 1.41.3.3 Heterogeneous Sonochemistry: Reactions of Solids with Liquids 737 1.41.4 CONCLUSIONS 738 1.41.5 REFERENCES 739 1.41.1 INTRODUCTION Ultrasonic irradiation of liquids causes high-energy chemical reactions to occur, often with the emission of light.1–3 The origin of sonochemistry and sonoluminescence is acoustic cavitation: the formation, growth, and implosive collapse of bubbles in liquids irradiated with high-intensity sound. The collapse of bubbles caused by cavitation produces intense local heating and high pressures, with very short lifetimes. In clouds of cavitating bubbles, these hot-spots4–6 have equiva- lent temperatures of roughly 5,000 K, pressures of about 1,000 atm, and heating and cooling rates above 1010 KsÀ1. In single bubble cavitation, conditions may be even more extreme. Thus, cavita- tion can create extraordinary physical and chemical conditions in otherwise cold liquids. When liquids that contain solids are irradiated with ultrasound, related phenomena can occur. When cavitation occurs near an extended solid surface, cavity collapse is non-spherical and drives high-speed jets of liquid into the surface.7 These jets and associated shock waves can cause substantial surface damage and expose fresh, highly heated surfaces. -
Advanced Organic Chemistry/ Organic Synthesis – CH 621 Ultrasound
Advanced Organic Chemistry/ Organic Synthesis – CH 621 Ultrasound Assisted Organic Synthesis (Sonochemistry) Bela Torok Department of Chemistry University of Massachusetts Boston Boston, MA 1 Ultrasonics/Sonochemistry - Historical Overwiev Ultrasonics - Ultrasounds (20-10 000 kHz) - 1880 Piezoelectricity (Curie brothers) - 1893 Galton - 1912 TITANIC - 1912 Behm (Echo technique) - 1917 Langevin (Ultrasonic variation, Icebergs, Submarines) - 1945 Application in chemistry 2 Ultrasonics/Sonochemistry –Basics Frequency ranges of sound 3 Ultrasonics/Sonochemistry – Basics Sound transmission through a medium 4 Ultrasonics/Sonochemistry – Acoustic Cavitation Bubble size and cavitation dynamics Formation of an acoustic bubble Transient cavitation 5 Ultrasonics/Sonochemistry – Acoustic Cavitation Acoustic cavitation in a homogeneous liquid Suslick - ~ 4-5000 K 6 Ultrasonics/Sonochemistry – Acoustic Cavitation Acoustic cavitation in solid/liquid system 7 Ultrasonics/Sonochemistry – Acoustic Cavitation Acoustic cavitation in solid/liquid system 8 Ultrasonics/Sonochemistry – Acoustic Cavitation Acoustic cavitation in liquid/liquid system 9 Ultrasonics/Sonochemistry – Sonochemical Effect Specific ultrasonic effect ? Yes and No No - another internal heating approach Yes - The temperature dependence of EA of different reactions could be significantly different – change in selectivities - Very effective mixing - Cavitation - Surface cleaning 10 Ultrasonics/Sonochemistry – Experimental Parameters 1. Acoustic frequency Increasing frequency – increasing energy -
New Trends in C–C Cross-Coupling Reactions: the Use of Unconventional Conditions
molecules Review New Trends in C–C Cross-Coupling Reactions: The Use of Unconventional Conditions Marta A. Andrade and Luísa M. D. R. S. Martins * Centro de Química Estrutural and Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal; [email protected] * Correspondence: [email protected]; Tel.: +35-121-841-9389 Academic Editor: Giuseppe Cirillo Received: 30 October 2020; Accepted: 20 November 2020; Published: 24 November 2020 Abstract: The ever-growing interest in the cross-coupling reaction and its applications has increased exponentially in the last decade, owing to its efficiency and effectiveness. Transition metal-mediated cross-couplings reactions, such as Suzuki–Miyaura, Sonogashira, Heck, and others, are powerful tools for carbon–carbon bond formations and have become truly fundamental routes in catalysis, among other fields. Various greener strategies have emerged in recent years, given the widespread popularity of these important reactions. The present review comprises literature from 2015 onward covering the implementation of unconventional methodologies in carbon–carbon (C–C) cross-coupling reactions that embodies a variety of strategies, from the use of alternative energy sources to solvent- free and green media protocols. Keywords: cross-coupling reactions; microwave irradiation; ultrasounds; mechanochemistry; solvent-free; water; ionic liquids; deep eutectic solvents; sustainability 1. Introduction Cross-coupling reactions have attracted and inspired researchers in the academia and industry for decades, given its significance as a synthetic tool in modern organic synthesis. The continuous interest in cross-coupling reactions, with more than 40 years of history, has been mostly driven by its valuable contributions and applications in the medicinal and pharmaceutical industries. -
Sonochemical and Sonoelectrochemical Production of Hydrogen-An Overview 2 Md Hujjatul Islam, Odne S
1 1 Sonochemical and Sonoelectrochemical Production of Hydrogen-An Overview 2 Md Hujjatul Islam, Odne S. Burheim and Bruno G. Pollet* 3 4 Department of Energy and Process Engineering, 5 Faculty of Engineering, 6 Norwegian University of Science and Technology (NTNU), 7 NO-7491 Trondheim, Norway 8 *[email protected] 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 2 36 Abstract 37 38 Reserves of fossil fuel such as coal, oil and natural gas on earth are finite. Also, the continuous use 39 and burning of these fossil resources in industrial, domestic and transport sectors results in the 40 extremely high emission of greenhouse gases into the atmosphere. Therefore, it is necessary to 41 explore pollution free and more efficient energy sources in order to replace depleting fossil fuels. 42 The use of hydrogen as an alternative fuel source is particularly attractive due to its very high 43 specific energy compared to other conventional fuels. Hydrogen can be produced through various 44 process technologies such as thermal, electrolytic and photolytic processes. Thermal processes 45 include gas reforming, renewable liquid and biooil processing, biomass and coal gasification; 46 however, these processes release a huge amount of greenhouse gases. Production of hydrogen from 47 water using ultrasound could be a promising technique to produce clean hydrogen. Also, using 48 ultrasound in water electrolysis could be a promising method to produce hydrogen where 49 ultrasound enhances electrolytic process in several ways such as enhanced mass transfer, removal 50 of bubbles and activation of the electrode surface. -
1 Effects of High Intensity Ultrasound on Disaggregation of a Macromolecular 1 Procyanidin-Rich Fraction from Vitis Vinifera L
1 Effects of high intensity ultrasound on disaggregation of a macromolecular 2 procyanidin-rich fraction from Vitis vinifera L. seed extract and evaluation of its 3 antioxidant activity 4 5 Ana Muñoz-Labrador, Marin Prodanov and Mar Villamiel* 6 *Instituto de Investigación en Ciencias de la Alimentación CIAL (CSIC-UAM).C/Nicolás 7 Cabrera 9, Universidad Autónoma de Madrid, 28049 Madrid, España. 8 9 10 11 *Author to whom correspondence should be addressed: 12 Tel: +34 910017951 13 E-mail: [email protected] 14 1 15 Abstract 16 The impact of high intensity ultrasound (US, 45 and 20 kHz) on a purified macromolecular 17 fraction (more than 85% of polymeric procyanidins) from grape seed extract was 18 investigated. Matrix-Assisted Laser Desorption/Ionisation (MALDI TOF), Reverse Phase 19 High Performance Liquid Chromatography (RP-HPLC) and Fourier-transform infrared 20 spectroscopy (FTIR) revealed a modification in the chemical structure of these 21 macromolecules treated by US and, particularly, bath US produced a considerable increase 22 of up to 49, 41 and 35%, respectively, of catechins and oligomeric and polymeric 23 procyanidin contents of the treated purified fraction. Bath US also produced, an important 24 increase in the number of procyanidins with higher molecular mass (up to decamers) and an 25 overall increase in the mass signal intensities in most of the detected B-type procyanidin 26 series, as well as an important increase of the antioxidant activity of the macromolecular 27 fraction of procyanidins. These results could be ascribed to a certain disaggregation of 28 procyanidins linked to other biopolymers, such as proteins and/or polysaccharides, 29 indicating that US is an efficient technology to modify the chemical structure and hence the 30 bioactivity of tannins. -
Analytical Sonochemistry: a Review
Journal of Automatic Chemistry, Vol. 10, No. 2 (April-June 1988), pp. 88-94 Analytical sonochemistry: a review P. Linares, F. Lizaro, M. D. Luque de Castro and Sample pretreatment M. Valcircel Department ofAnalytical Chemistry, Faculty of Sciences, University of Cdrdoba, The most versatile step of the analytical process, sample Cdrdoba, Spain preparation, has been aided by the use of ultrasound in a variety of forms. Different ways to favour reaction Analytical chemistry is one of the chemical areas where ultrasonic development have been used and compared by a number radiation has been only infrequently used (namely in sample of researcher groups. Agricultural and environmental pretreatment, separations, automatic analytical systems and chemistry have so far been the areas of applied analysis clinical analysis). This auxiliary technique would constitute a benefiting to the greatest extent from the use of ultra- powerful aid in the automation of several steps in analytical sound. processes: its advantages and disadvantages, as well as its use and potential in the area of non-invasive detectors, are reviewed in this paper. Methods for extraction of different analytes from a soil or plant sample are still far from satisfactory and methods based on substantially different principles continue to be The of ultrasonic waves, characterized by a propagation with the aim of and avoiding minimum of 16 results in fluid proposed improving yields frequency kHz, rapid contamination and alteration of the material. Unfortu- movement through compression and rarefaction, the nately, it seems to fulfil both objectives waves rise to the cavitation impossible generated giving pheno- Another arises from the rather menon, i.e. -
Ultrasound in Electrochemical Degradation of Pollutants
Chapter 10 Ultrasound in Electrochemical Degradation of Pollutants Gustavo Stoppa Garbellini Additional information is available at the end of the chapter http://dx.doi.org/10.5772/47755 1. Introduction The increase of industrial activities and intensive use of chemical substances such as petroleum oil, polycyclic aromatic hydrocarbons, BTEX (benzene, toluene, ethylbenzene and xylenes), chlorinated hydrocarbons as polychlorinated biphenyls, trichloroethylene and perchloroethylene, pesticides, dyes, dioxines and heavy metals have been contributing to environmental pollution with dramatic consequences in atmosphere, waters and soils (Martínez-Huitle & Ferro, 2006; Megharaj et al., 2011). Electrochemical technologies have been extensively used for degradation of toxic compounds since these technologies present some advantages, among them: versatility, environmental compatibility and potential cost effectiveness (Martínez-Huitle & Ferro, 2006; Chen, 2004; Ghernaout et al., 2011; Panizza & Cerisola, 2009). However, a loss in the efficiency of such degradation processes is observed due to the adsorption and/or insolubilization of the oxidation and/or reduction products on the electrodes surfaces (Garbellini et al., 2010; Lima Leite et al., 2002). In this sense, power ultrasound has been employed to overcome such electrode fouling problem (passivation) due to the ultrasound ability for cleaning the electrode surface, called sonoelectrochemistry (Compton et al., 1997). The production of ultrasound is a physical phenomenon based on the process of creating, growing and imploding cavities of steam and gases, known as cavitation. During the compression step, the pressure is positive, while the expansion results in vacuum called negative pressure formed in a compression-expansion cycle that generates cavities (Mason, 1990; Martines et al., 2000). In chemistry, ultrasound has been used in organic synthesis, polymerization, sonolysis, preparation of catalysts and sonoelectrosynthesis (Mason, 1990; Martines et al., 2000).