Handbook of ultrasonics and sonochemistry

Ming Ronnier Luo Editor Encyclopedia of Color Science and Technology 3Reference Handbook of Ultrasonics and Sonochemistry Muthupandian Ashokkumar Editor-in-Chief Francesca Cavalieri • Farid Chemat Kenji Okitsu • Anandan Sambandam Kyuichi Yasui • Bogdan Zisu Section Editors Handbook of Ultrasonics and Sonochemistry With 649 Figures and 99 Tables Editor-in-Chief Muthupandian Ashokkumar School of Chemistry The University of Melbourne Melbourne, VIC, Australia Section Editors Francesca Cavalieri Department of Chemical Sciences and Technologies University of Rome “Tor Vergata” Rome, Italy Farid Chemat Department of Chemistry Universite d’Avignon et des Pays de Vaucluse Avignon cedex 1, France Kenji Okitsu Department of Materials Science Osaka Prefecture University Osaka, Japan Anandan Sambandam Department of Chemistry National Institute of Technology Tiruchirappalli Tiruchirappalli, TN, India Kyuichi Yasui National Institute of Advanced Industrial Science and Technology (AIST) Nagoya, Japan Bogdan Zisu RMIT University Melbourne, VIC, Australia ISBN 978-981-287-277-7 ISBN 978-981-287-278-4 (eBook) ISBN 978-981-287-279-1 (print and electronic bundle) DOI 10.1007/978-981-287-278-4 Library of Congress Control Number: 2016939268 # Springer Science+Business Media Singapore 2016 This work is subject to copyright All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed The use of general descriptive names, registered names, trademarks, service marks, etc in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication Neither the publisher nor the authors or the editors give a warranty, express or implied, with respect to the material contained herein or for any errors or omissions that may have been made Printed on acid-free paper This Springer imprint is published by Springer Nature The registered company is Springer Science+Business Media Singapore Pte Ltd Preface Soundwaves, responsible for verbal communication between human beings and to some extent between living organisms, are capable of promoting chemical reactions and processing of materials While many research articles, reviews, and books are available on selected aspects related to the topics covered in this Handbook, a single reference material that provides the current status of research areas ranging from fundamental aspects to various applications is missing in the literature In order to overcome this shortfall, the Handbook of Ultrasonics and Sonochemistry (HBUS) has been developed with contributions from expertise in different areas of ultrasonics and sonochemistry HBUS consists of five sections: Fundamental Aspects, Nanomaterials, Environmental Remediation, Biomaterials, and Food Processing Each section contains about ten chapters dealing with reviews of current literature and in some cases providing new results While some chapters provide historical background of relevant topics, most focus on recent developments and current status of the research areas The first section on fundamental aspects aims at providing the basics of acoustic cavitation How ultrasound interacts with gas bubbles and grows them by rectified diffusion, theoretical aspects of cavitation, how the strong physical effects and chemical reactions are generated during cavitation, and what issues are still remaining unresolved are some topics covered in this section In addition, acoustic cavitation in a microchannel, atomization, and a brief account of hydrodynamic cavitation are also included in this section The section on nanomaterials deals with the synthesis of a variety of nanomaterials using the physical and chemical effects generated during acoustic cavitation and their applications In addition to synthesizing materials, this chapter also deals with processing of materials such as micelles There is a significant crossover between Sections II and III, which could be expected as materials are used in environmental remediation In both sections, the advantages of using hybrid techniques are highlighted A combination of ultrasound and electrochemistry or photocatalysis seems to offer synergistic effects under specific experimental conditions Section III not only deals with processing of organic pollutants in aqueous environment, but also highlights the use of acoustic cavitation for the treatment of waste oils In both sections, the use of hydrodynamic cavitation for synthesizing nanomaterials and environmental remediation is discussed The physical and chemical events arising from acoustic cavitation have been extensively v vi Preface used for synthesizing functional biomaterials, which is focused in Section IV Ultrasonically synthesized core-shell materials are found to possess unique physical and functional properties as highlighted in this section The last section of HBUS deals with one of the growing applications of ultrasound, food processing In recent years, the physical forces generated during acoustic cavitation have been found useful for improving the functional properties of food and dairy systems Food quality, functionality, nutritional properties, and storage stability are some processes that could be improved by sonication The high quality chapters in HBUS are contributed by leading researchers The Editor-in-Chief and Section Editors sincerely acknowledge the authors for their time commitment and quality contributions The Editor-in-Chief thanks the Section Editors for their involvement in HBUS project, who should take the full credit for organizing individual sections that include choosing leading researchers, sending invitations, organizing review processes, and completing the overall process on time The Editor-in-Chief would also like to acknowledge Springer and its staff for their effort in making HBUS possible In particular, Stephen Yeung, Tina Shelton, and Alexa Singh have been on our (Editor-in-Chief and Editors) toes to make sure we deliver what we promised, on time And finally, it should be noted that HBUS is a great addition to academic literature and would help a wide range of communities including academic researchers, graduate students, and industries to understand and expand their knowledge in ultrasonics and sonochemistry from fundamentals to possible industrial applications Muthupandian Ashokkumar Editor-in-Chief Contents Volume Part I Fundamental Aspects Bubble Dynamics and Observations Robert Mettin and Carlos Cairós Acoustic Bubbles, Acoustic Streaming, and Cavitation Microstreaming Richard Manasseh 33 The Growth of Bubbles in an Acoustic Field by Rectified Diffusion Thomas Leong, Muthupandian Ashokkumar, and Sandra Kentish 69 99 Importance of Sonication and Solution Conditions on the Acoustic Cavitation Activity Judy Lee 137 Acoustic Cavitation in a Microchannel Siew-Wan Ohl and Claus-Dieter Ohl Acoustic Bubbles and Sonoluminescence Pak-Kon Choi 177 Experimental Observation of an Acoustic Field Nobuki Kudo 207 Ultrasonic Atomization Susumu Nii 239 259 Unsolved Problems in Acoustic Cavitation Kyuichi Yasui vii viii Part II Contents Nanomaterials 293 Sonoelectrochemical Synthesis and Characterization of Nanomaterials Guohai Yang and Jun-Jie Zhu 295 Catalytic Applications of Noble Metal Nanoparticles Produced by Sonochemical Reduction of Noble Metal Ions Kenji Okitsu and Yoshiteru Mizukoshi 325 Ultrasonic Synthesis of Polymer Nanoparticles Boon Mian Teo 365 Ultrasonic Synthesis of Ceramic Materials: Fundamental View Naoya Enomoto 395 Ultrasound-Assisted Synthesis of Nanoparticles for Energy and Environmental Applications Sundaram Ganesh Babu, Bernaurdshaw Neppolian, and Muthupandian Ashokkumar Synthesis of Inorganic, Polymer, and Hybrid Nanoparticles Using Ultrasound S Shaik, S.H Sonawane, S.S Barkade, and Bharat Bhanvase Ultrasonic Modification of Micelle Nanostructures Nor Saadah Mohd Yusof and Muthupandian Ashokkumar 423 457 491 Ultrasound-Assisted Synthesis of Electrocatalysts for Hydrogen Production Pavel V Cherepanov and Daria V Andreeva 525 Sonophotocatalytic Degradation of Organic Pollutants Using Nanomaterials J Theerthagiri, R.A Senthil, D Thirumalai, and J Madhavan 553 Ultrasonic Synthesis of Nanomaterials for Photocatalytic Removal of Pollutants from Wastewater Bin Xue 587 Part III 623 Environmental Remediation Mathematical Models for Sonochemical Effects Induced by Hydrodynamic Cavitation Vijayanand S Moholkar 625 Sonophotocatalytic Mineralization of Environmental Contaminants Present in Aqueous Solutions P Sathishkumar, R.V Mangalaraja, and Sambandam Anandan 673 Contents ix Advanced Oxidation Processes Using Ultrasound Technology for Water and Wastewater Treatment Younggyu Son Metals Oxides and Doped Metal Oxides for Ultrasound and Ultrasound Assisted Advanced Oxidation Processes for the Degradation of Textile Organic Pollutants G Kumaravel Dinesh, T Sivasankar, and Sambandam Anandan 711 733 Degradation of Organic Micropollutants by Hydrodynamic and/or Acoustic Cavitation Patrick Braeutigam 761 Sonochemical Degradation of Aromatic Compounds, Surfactants, and Dyes in Aqueous Solutions Kenji Okitsu, Ben Nanzai, and Kandasamy Thangavadivel 785 Removal of Heavy Metal from Wastewater Nalenthiran Pugazhenthiran, Sambandam Anandan, and Muthupandian Ashokkumar 813 Role of Process Intensification by Ultrasound Bhakar Bethi, Shirish Sonawane, and Bharat Bhanvase 841 Sonochemical Synthesis of Zinc Sulfide Photocatalysts and Their Environmental Applications Jerry J Wu and Gang-Juan Lee 867 Combined Treatment Processes Based on Ultrasound and Photocatalysis for Treatment of Pesticide Containing Wastewater Pankaj N Patil and Parag R Gogate 901 Conversion of Refined and Waste Oils by Ultrasound-Assisted Heterogeneous Catalysis Daria C Boffito, Edith Martinez-Guerra, Veera G Gude, and Gregory S Patience 931 Volume Part IV Biomaterials 965 Ultrasonic Coating of Textiles by Antibacterial and Antibiofilm Nanoparticles Ilana Perelshtein, Nina Perkas, and Aharon Gedanken 967 995 Ultrasound-Assisted Functionalization of Polyphenols Elisavet D Bartzoka, Heiko Lange, and Claudia Crestini Ultrasonic Separation of Food Materials 1469 Batch (Single Unit) Batch reactors can be relatively straightforward to design and operate and can be a useful first step toward developing a scale-up process for any potential ultrasonic food separation application These reactors will inevitably consist of a fixed processing volume where standing waves are established The food material to be separated will be loaded into the interrogation volume, processed, and then removed High-density materials will sediment to the base of the reactor; low-density material will rise to the top of the reactor by buoyancy Inlets and outlets located strategically to maximize product recovery after separation are necessary to ensure efficient product collection The required duration of processing (i.e., residence time) will be determined by the energy input, volume processed, and the rate at which collected food material will separate by buoyancy or sedimentation One of the possible advantages of batch separation is that the residence time, which influences the extent of separation, can be more effectively controlled for a given batch of food material and hence may be more suitable, e.g., for fractionation-type applications Continuous Flow The design of continuous systems is more challenging to implement and operate since forces arising from product flow must be balanced with the acoustic forces during separation The advantage however is that higher throughput can be achieved Whereas microscale systems can implement flow-split devices to harvest product [2], large-scale food systems have standing waves consisting of many nodal planes that make this impossible Instead, overflow and underflow devices are the most amenable method to collect product High-density material will collate at the bottom of the reactor and can be intermittently swept through the underflow area of the chamber Low-density material will float to the top and can, by slow flow motion, be displaced to an overflow collection area Carefully designed control systems must be put in place in order to maintain product quality (i.e., target concentrations for the separation process) For example, parameters such as energy input or rate of product flow can be adjusted to tailor the resultant separation achieved at the outlets The rate of product flow however must be below a certain Reynolds number to ensure laminar flow (which is dependent on the cross section of the flow area) For cylindrical pipes, this value is ~2,000 Flow regimes which are extremely turbulent are generally not suitable for megasonic separation, since mixing of the product will occur in such a situation, preventing effective separation Nevertheless, the acoustic radiation force can in some cases be strong enough to overcome the mixing that occurs during processing Separation can be successful in the presence of high mixing and flow if there is additional mechanism such as coalescence or flocculation that can hold collected food material together Continuous flow ultrasonic separation can be a useful addition to existing processing operations, where the predisposition or pretreatment of product prior 1470 T Leong to a downstream separation unit will provide a benefit for the recovery of a highvalue material post-decantation or centrifugation In this situation, the ultrasonics serve to initiate agglomeration and/or coalescence of suspended food material, as well as enhance the extraction of product that may be trapped in solid raw materials This intervention enhances the rate at which the downstream process achieves separation and also increases the recoverable yield of the food material One example in which such an operation has been proven useful is in the palm oil milling industry, where the predisposition of material enhances the recoverable oil from the plant mesocarp [3] Applications This section will assess designs established to date at various scales for a range of applications The most prominent example is the continuously operating separation reactor implemented in a high-tech palm oil mill, where the ex-screw press feed is treated for increased palm oil recovery Other examples are the utilization of ultrasonics for milk fat separation and fractionation, algal cells in the production of algal oils, and bacteria, yeasts, and other cells in fermentation systems Applications of Ultrasound for Palm Oil Separation A typical palm oil milling operation in Malaysia may experience a loss of recoverable product in the effluent with a potential revenue of >$200,000 USD per year The application of ultrasonic separation technology to existing plant operations can be effective in minimizing product loss and to enhance clarification efficiency Juliano et al [3, 32] successfully demonstrated the ability to enhance oil recovery from the extract obtained from pressed oil palm fruit mesocarp at lab and pilot scale This success has recently been extended to full-scale commercial operation, capable of processing throughput of up to 45 tons per hour (Fig 6) The system depicted can be applied directly to existing palm oil mills Here, the feed coming directly from the ex-screw press is passed through a vertical chamber where droplets of palm oil product are predisposed into larger droplets An additional recovery of between 1% and 10 % product is achieved in the process, which eliminates virtually any oil being lost to the effluent stream The success of the ultrasonic application is due to the ultrasound (applied at 600 kHz frequency) generating physical “rubbing” of the plant material This activity assists the extraction of oil from the vegetal matter The oil in the bulk liquid is then coalesced into larger droplets by the acoustic standing waves, resulting in faster oiling-off by gravity settling in downstream processing Thus, ultrasonic application in this case improves the total recoverable oil and the rate of separation The use of this technology has revolutionized the design of future palm oil plants where the environmental footprint can be significantly reduced by decreasing the Ultrasonic Separation of Food Materials 1471 Fig (a) Schematic representation of the megasonic palm oil separation reactor: the rectangles represent a transducer/transmission plate setup; (b) photograph of the commercially operating megasonic reactor (@45 t/h; Â 600 kHz, kW each) (Taken from Leong et al [20] with permission of Springer Copyright Springer Science +Business Media New York 2015) volumes utilized in the vertical clarification tanks, the amount of decanter centrifuges, and the oil loss into effluents For a typical palm oil milling operation, this equates to an increased profit averaging between $500,000 and $2,000,000 USD per year Enhanced Creaming of Milk Fat Globules The dairy products we consume and enjoy such as milk, cheese, and butter have usually undergone a separation process that removes or concentrates the fat in the milk to a product specification defined by the manufacturer In the dairy industry, this separation is typically achieved by using a centrifuge, which removes the fat from milk by application of intense g-forces by rapid spinning Since milk fat is a valuable commodity, a common practice involves removing all of the fat from the milk and recombining the separated cream as required back into the skimmed milk to make products with standardized fat concentrations Traditionally, separations were performed simply by letting the cream in milk rise to the top where it could be skimmed off Such practices are slow, requiring many hours to achieve sufficient separation They are however still performed 1472 T Leong today, primarily by cheese makers like those in Northern Italy famed for Parmesan and Romano cheeses [33] These cheese makers continue to apply these traditional methods, since it creates milk with a fat size distribution that contributes to the unique flavors in these cheeses The process creates a point of differentiation that cannot be achieved using centrifugation [34] Ultrasonic separation has been recognized as a complementary technology that can significantly enhance the separation rate of fat from milk by “natural” methods [27] When an acoustic standing wave is applied to volume of milk, the fat globules collect at the pressure antinodes, which can be observed as “bands” of fat globules This phenomenon was observed by Miles et al [35] in a small cuvette container The milk fat globules collecting and concentrating at the pressure antinodes have an enhanced probability to aggregate into larger floccules As fat globules collect into larger floccules, they begin to rise more rapidly to the surface due to the increased hydrodynamic radius as described by Stokes’ Law [36] A first-approach scale-up (up to L volume) in a batch system was demonstrated by Juliano et al [29] using a recombined milk emulsion For a recombined milk emulsion, rapid separation could be achieved using ultrasound at an operating frequency of 400 kHz in a vessel with a transducer-to-reflector distance between ~18 and 20 cm At these distances, a frequency of MHz was less effective than 400 kHz and a frequency of MHz again less effective than MHz The parameters found to achieve rapid separation of a recombined milk emulsion, however, were not successful in separating fat globules in natural whole milk within the same vessel [37] Several reasons can be attributed to this Natural whole milk has different properties, namely, particle size distribution and surface composition, compared to a recombined milk emulsion The mean particle size is smaller in natural whole milk and so requires high-frequency ultrasound or strong acoustic energy density to manipulate effectively In order to effectively apply highfrequency ultrasound >1 MHz, the geometry with respect to the distance between transducer and reflector should also be small to minimize attenuation Leong et al [27, 31] applied these concepts to achieve separation using natural whole milk Leong et al showed that higher-frequency ultrasound, in this case >1 MHz, could effectively manipulate and separate the fat globules present in natural whole milk provided that a short transducer-reflector separation distance (between 30 and 85 mm) was used Furthermore, the application of dual transducers in a parallel arrangement was found to influence more rapid skimming of fat due to the ability to achieve a higher energy density per unit volume Leong et al [31] also showed that there is an “optimal” temperature range over which the rate of milk fat separation is greatest In this case, a temperature range between 20 and 60  C offered fast separation of milk fat in the experimental trials Leong et al [38] have recently highlighted the ability of ultrasonic separation to initiate fractionation of milk fat globules into streams with enhanced proportions of small or large fat globules These streams may have potential for creating dairy products with enhanced microstructure This was achieved by manipulating the duration of processing and collecting product at defined intervals at specific locations within the reactor Ultrasonic Separation of Food Materials 1473 Notably, it was established that the milk fat became distributed in the separation vessel after sonication, such that the smallest fat globules were retained toward the bottom of the vessel and large-sized fat globules were enriched within the cream collected near the top of the vessel These fractions positioned at the top and bottom of the vessel can be collected specifically by overflow/underflow Similar techniques can be used to split streams of food ingredients containing specific particle size distributions Microbial and Algal Cell Separation A diverse group of prokaryotic and eukaryotic photosynthetic microorganisms known as microalgae can be used to produce edible oils and other biofuels that can be used as an attractive alternative sustainable energy source These algae are grown in aqueous medium such as water, but their separation, often by centrifugation, is identified as being energy intensive The use of ultrasonic standing waves to concentrate microalgae is identified as a significant advancement toward improving their dewatering efficiency Ultrasonic separation has been used to separate the algal cells from water [39, 40] Bosma et al [39] applied 2.1 MHz to algae flowing continuously through a small volume and achieved a separation efficiency of over 90 %, albeit at low flow rates of only 4–6 L per day Although production flow rates are currently low, continued work to scale up ultrasonic separation systems by applying key concepts as detailed in this chapter will bring these products closer to market Fermentation Products Ultrasonic separation can also be used as an alternative cell-retention system for fermentation and cell culturing applications [41] Recombinant proteins, amino acids, and antibodies are some examples of the high-value products which can be delivered in these applications Studies have shown that selective retention of viable versus nonviable cells is possible [42] reducing the need to “bleed out” product during operation, thereby improving production Such systems are commercially available with the development of BioSep™, and could also be readily implemented into food applications such as fermentation tanks in the beer and wine industry BioSep™ units are available from throughputs as small as 10 L/day up to 200 L/day Gorenflo et al [41] found that these types of systems performed reliably and achieved separation efficiencies between dead and viable cells of greater than 95 % Typical operation employs a stop time of s (for run time of 120 s) to facilitate the removal of cells out of the acoustically active region The advantage of ultrasound separation in such applications is that the technique is relatively simple and offers nearly maintenance-free operation by reducing the need to periodically bleed out product The high-frequency ultrasound employed limits any potential physical or chemical change to the product, thereby preserving the quality 1474 T Leong It should be noted the 20-fold scale-up from 10 L per day perfusion rates to 200 L per day was based on using four parallel compartments in one separator with a single controller This is because scale-up is limited by the geometry in which a strong standing wave can be established when using high-frequency ultrasound To be successful in the food industry and to accommodate the large throughputs required in beer and wine processing, scale-up to several tons per day is essential For achieving these higher flow rates, a further scale-out of the process by using several 200 L/day reactors is recommended, since increasing the size of the separation chamber or flow rate through the chamber may reduce the overall efficiency of the system Alternatively, different design configuration, including adjustments of the process conditions, may offer reasonable performance without the requirement of simple numbering up, which may be cost prohibitive due to the high capital costs of not only the ultrasonic transducers but also the reaction chambers themselves Future Applications Potential designs can be established for a number of other applications such as effluent treatments, separation of starch suspensions, and water recycling These reactors will have similar design considerations to the abovementioned applications The scale of the process will determine the required throughputs, and the nature of the material to be separated will influence the selection of the appropriate operating parameters For example, the ultrasonic frequency selection will be governed by the material to be separated and its properties such as particle size, density, and compressibility This in turn determines the suitable geometries that can be designed for the separation reactor To achieve the required throughputs, scale-up may be achievable if lower frequencies (