51
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Hewage SA, Kewalramani J, Meegoda JN. Stability of nanobubbles in different salts solutions. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2020.125669] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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52
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Tanaka S, Terasaka K, Fujioka S. Generation and Long‐Term Stability of Ultrafine Bubbles in Water. CHEM-ING-TECH 2020. [DOI: 10.1002/cite.202000143] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Shunya Tanaka
- Keio University School of Science for Open and Environmental Systems Graduate School of Science and Technology 3-14-1 Hiyoshi, Kohoku-ku 223-8522 Yokohama Kanagawa Japan
| | - Koichi Terasaka
- Keio University Department of Applied Chemistry Faculty of Science and Technology 3-14-1 Hiyoshi, Kohoku-ku 223-8522 Yokohama Kanagawa Japan
| | - Satoko Fujioka
- Keio University Department of Applied Chemistry Faculty of Science and Technology 3-14-1 Hiyoshi, Kohoku-ku 223-8522 Yokohama Kanagawa Japan
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53
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Kyzas GZ, Favvas EP, Kostoglou M, Mitropoulos AC. Effect of agitation on batch adsorption process facilitated by using nanobubbles. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2020.125440] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Abstract
Submicron-sized bubbles are now officially called ultrafine bubbles (UFBs) by the international standard. The concentration of UFBs is generally low (<109 particles/mL; <0.001 vol%) compared to other colloidal dispersions. To overcome this practical problem, we concentrated UFBs in ultrapure water prepared by a commercial UFB generator and quantified the effect of rotary evaporation of the dispersion media on the stability of UFBs. The UFB dispersions were characterized by a particle tracking analysis (PTA) instrument. The experimental results showed that the UFBs can be diluted and concentrated without changing the size distribution and there was little or no loss of UFBs. By using a rotary evaporator, UFB dispersions were about 30-fold concentrated and the resultant number concentration reached over 3 × 1010 particles/mL. Increasing the concentration of UFBs allowed for satisfactory dynamic light scattering (DLS) measurements. The differences among the three algorithms for analyzing the raw data, i.e., autocorrelation function, obtained by DLS are discussed, along with the characteristics of the particle size distribution derived from each algorithm.
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55
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Zhou W, Liu L, Zhou B, Weng L, Li J, Liu C, Yang S, Wu C, Liu K. Electrokinetic potential reduction of fine particles induced by gas nucleation. ULTRASONICS SONOCHEMISTRY 2020; 67:105167. [PMID: 32442929 DOI: 10.1016/j.ultsonch.2020.105167] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 04/10/2020] [Accepted: 05/07/2020] [Indexed: 06/11/2023]
Abstract
Electrokinetic potential of particles has been extensively studied in colloidal systems over the past century, while up to date, the influence of gas on electrokinetic behaviors of particles has not been fully understood yet. In this study, the electrokinetic response of particles to gas nucleation was systematically investigated with coal as the object. The results showed that the nucleation of gas (both on particle surfaces and in water) significantly changed the particle' electrokinetic behaviors. Higher gas content and particle's surface hydrophobicity normally trigger more intensive gas nucleation, thus inducing more significant reduction of particle zeta potential. After gas nucleation, numerous nanobubbles (NBs) appear in the suspensions mainly in two forms: NBs adhering onto solid surfaces (ANBs) and NBs stagnating in bulk solutions (BNBs). ANBs not only enhance the surface heterogeneity, but also cause the "steric hindrance" effect, and electric double layer (EDL) overlapping and associated ions shielding towards charged particles, which significantly decrease their electrokinetic potentials. Although BNBs can also reduce the zeta potential of particles by EDL compressing, their functions are rather limited.
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Affiliation(s)
- Weiguang Zhou
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Liming Liu
- School of Innovation and Entrepreneurship, Southern University of Science and Technology, Shenzhen 518055, China
| | - Baonan Zhou
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Li Weng
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China; Clean Energy Institute, Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen 518055, China
| | - Junguo Li
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China; Clean Energy Institute, Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen 518055, China
| | - Cheng Liu
- School of Resources and Environment Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Siyuan Yang
- School of Resources and Environment Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Changning Wu
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China; Clean Energy Institute, Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Ke Liu
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China; School of Innovation and Entrepreneurship, Southern University of Science and Technology, Shenzhen 518055, China; Clean Energy Institute, Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen 518055, China.
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56
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Li P, Zhang M, Lei W, Yao W, Fan R. Effect of Nanobubbles on the Slime Coating of Kaolinite in Coal Flotation. ACS OMEGA 2020; 5:24773-24779. [PMID: 33015495 PMCID: PMC7528324 DOI: 10.1021/acsomega.0c03380] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 09/07/2020] [Indexed: 05/06/2023]
Abstract
Understanding the coating behavior of fine gangue slimes in the presence of nanobubbles (NBs) is important for the application of NB technology in flotation. In this study, slime coating of kaolinite in the flotation of a low-ash coal using deionized (DI) water and NB water was investigated. Kaolinite was found to depress coal flotation by the formation of coating on coal surfaces, but its deleterious effect was less pronounced in the NB water with mitigated slime coating. Setting tests, Brunauer-Emmett-Teller surface area measurements, and dynamic light scattering were conducted to understand the underpinning mechanism. In comparison with DI water, the degree of kaolinite aggregation was enhanced in the NB water. The intensified self-aggregation of kaolinite platelets which appears to be induced by the presence of NBs reduces the solid-liquid interfacial area as well as the number of free kaolinite particles in the suspension, mitigating the coating of kaolinite on coal surfaces in NB water flotation.
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Affiliation(s)
- Panwu Li
- College
of Resources and Environmental Engineering, Wuhan University of Science and Technology, Wuhan 430081, China
| | - Ming Zhang
- College
of Resources and Environmental Engineering, Wuhan University of Science and Technology, Wuhan 430081, China
- Hubei
Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic
Mineral Resources, Wuhan 430081, China
| | - Wang Lei
- College
of Resources and Environmental Engineering, Wuhan University of Science and Technology, Wuhan 430081, China
| | - Wei Yao
- College
of Resources and Environmental Engineering, Wuhan University of Science and Technology, Wuhan 430081, China
| | - Rong Fan
- CSIRO
Mineral Resources, Private Bag 10, Clayton South, Victoria 3169, Australia
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57
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Kim MS, Han M, Kim TI, Lee JW, Kwak DH. Effect of nanobubbles for improvement of water quality in freshwater: Flotation model simulation. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.116731] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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58
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Zhou W, Liu K, Wang L, Zhou B, Niu J, Ou L. The role of bulk micro-nanobubbles in reagent desorption and potential implication in flotation separation of highly hydrophobized minerals. ULTRASONICS SONOCHEMISTRY 2020; 64:104996. [PMID: 32050142 DOI: 10.1016/j.ultsonch.2020.104996] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 12/13/2019] [Accepted: 02/03/2020] [Indexed: 06/10/2023]
Abstract
Micro-nanobubbles (MNBs) generated during hydrodynamic cavitation (HC) have been extensively studied in mineral processing field in the past two decades. Many researchers have claimed that MNBs can effectively promote the collection of fine particles in flotation, while studies on MNBs assisted mineral separation are rare. In this study, the role of bulk MNBs in desorbing flotation reagent was investigated, with the aim of illustrating the potential effects of MNBs on minerals separation. The results showed that bulk MNBs could efficiently remove the sodium oleate (NaOl) from diaspore surfaces, reducing the residual concentration of NaOl on solids, which was more significant when the amount of NaOl pre-adsorbed was relatively small. Furthermore, lower residual concentration of NaOl on solids caused by MNBs cleaning made the particles less hydrophobic and flocs more friable. Given that gangue entrapment in flocs was one of the main limits for high-selective flotation, the roles of MNBs in enhancing reagent desorption and associated flocs breakup and reorganization probably contribute to higher separation efficiency of different minerals, which was confirmed by the flotation results of diaspore/kaolinite mixture.
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Affiliation(s)
- Weiguang Zhou
- School of Minerals Processing & Bioengineering, Central South University, Changsha 410083, China; Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Ke Liu
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Long Wang
- College of Mining Engineering, North China University of Science and Technology, Tangshan, China
| | - Baonan Zhou
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Jiaojiao Niu
- Simon F.S. Li Marine Science Laboratory, School of Life Science, Chinese University of Hong Kong, Hong Kong, China
| | - Leming Ou
- School of Minerals Processing & Bioengineering, Central South University, Changsha 410083, China.
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59
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Jin J, Wang R, Tang J, Yang L, Feng Z, Xu C, Yang F, Gu N. Dynamic tracking of bulk nanobubbles from microbubbles shrinkage to collapse. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2020.124430] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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