Abstract
Mixing of nanopowders in an environmentally benign magnetically assisted fluidized bed (MAFB) system was studied. Examination of fluidization behavior of agglomerate particulate fluidization (APF; silica R974 or R972) and agglomerate bubbling fluidization (ABF; alumina or titania) nano-powders in un-assisted and MAFB systems confirmed previous results on decreased minimum fluidization velocity and increased bed expansion of APF and ABF powders due to magnetic assistance. APF and ABF powder mixtures behaved like APF powders with the bed expansions in between those of individual constituents. Unlike previous MAFB studies, fluidization as a function of time was studied to examine its influence on nano-mixing. With time, the bed expansion reduced, and reduction was faster as magnet-to-powder ratio increased from 0:1 to 5:1, although fluidization was sustained, confirmed via the pressure drop measurements. Reduction in bed expansion was attributed to change in the nature of nanoagglomerates, which showed increased density as a function of processing time, ruling out electrostatics or elutriation as major factors. Mixtures of silica (APF) and alumina (ABF), processed at various magnet-to-powder ratios, were characterized via statistical analysis from energy dispersive x-ray spectroscopy using field emission scanning electron microscope to compute homogeneity of mixing (HoM). Magnetic assistance improved the HoM as a function of time, and was strongly related to the product of number of magnets and time, similar to previous results in magnetically assisted impaction mixing (MAIM). The best achievable HoM was significantly better than unassisted fluidization and comparable to previous results for rapid expansion of high-pressure suspensions and MAIM.
Similar content being viewed by others
References
Ammendola P, Chicone R, Raganati F (2011a) Fluidization of binary mixtures of nanoparticles under the effect of acoustic fields. Adv Powder Technol 22:174–183
Ammendola P, Chicone R, Raganati F (2011b) Effect of mixture composition, nanoparticle density and sound intensity on mixing quality of nanopowders. Chem Eng Process 50:885–891
Aoki M, Ring TA, Haggerty JS (1987) Analysis and modeling of the ultrasonic dispersion technique. Adv Ceram Mater 2:209–212
Barrow R, Yang J, Davé RN, Pfeffer R (2007) Dry-mixing of sub-micron B and BaCrO4 particles for use in a time delay composition. SAFE J 35:7–13
Carter SA, Scott JC, Broack PJ (1997) Enhanced luminance in polymer composite light emitting device. Appl Phys Lett 71:1145–1147
Chu LW, Prakash KN, Tsai M-T, Lin IN (2008) Dispersion of nano-sized BaTiO3 powders in nonaqueous suspension with phosphate ester and their applications for MLCC. J Eur Ceram Soc 28:1205–1212
Danckwerts PV (1952) The definition and measurement of some characteristics of mixtures. Appl Sci Res A3:279–296
Ding P, Pacek AW (2008) De-agglomeration of goethite nanoparticles using ultrasonic comminution device. Powder Technol 187:1–10
Geldart D (1973) Types of gas fluidization. Powder Technol 7:285–292
Guo Q, Li Y, Wang M, Shen W, Yang C (2006a) Fluidization characteristics of SiO2 nanoparticles in an acoustic fluidized bed. Chem Eng Technol 29:78–86
Guo Q, Liu H, Shen W, Yan X, Jia R (2006b) Influence of sound wave characteristics on fluidization behaviors of ultrafine particles. Chem Eng J 119:1–9
Hakim LF, Portman JL, Casper MD (2005) Aggregation behavior of nanoparticles in fluidized bed. Powder Technol 160:149–160
Hellmig RJ, Ferkel H (1999) Effect of nanopowder deagglomeration on the densities of nanocrystalline ceramic green bodies and their sintering behavior. NanoStruct Mater 11:617–622
Hendrickson W, Kooyer R (2000) Process for making particle-coated solid substrates. US Patent 6037019
Huang C, Wang Y, Wei F (2007) Solids mixing behavior in a nano-agglomerate fluidized bed. Powder Technol 179:229–236
Imanaka N, Kohler J, Toshiyuki M (2000) Inclusions of nanometer-sized Al2O3 particles in a crystalline (Sc, Lu)2(WO4)3 matrix. J Am Ceram Soc 83:427–429
Kashyap M, Gidaspow D, Driscoll M (2008) Effect of electric field on the hydrodynamics of fluidized nanoparticles. Powder Technol 183:441–453
Kaye BH (1997) Powder mixing. Chapman & Hall, London
Le Bars N, Levitz P, Messier A, Francois M, Van Damme H (1995) Deagglomeration and dispersion of barium titanate and alumina particles in an organic medium. J Colloid Interface Sci 175:400–410
Lepek D, Valverde JM, Pfeffer R, Dave RN (2010) Enhanced nanofluidization by alternating electric fields. AIChE J 56:54–65
Lu XS, Li H (2000) Fluidization of CaCO3 and Fe2O3 particle mixtures in a transverse rotating magnetic field. Powder Technol 7:66–78
Marioth E, Kroeber H, Loebbecke S, Fuhr I, Krause H (2007) Deagglomeration and mixing of nanoparticles using the rapid expansion of supercritical dispersions. Paper presented at the annual Partec meeting 2007. Nuremburg, 7 April 2007
Mehrani P, Bi HT, Grace J (2005) Electrostatic charge generation in gas–solid fluidized beds. J Electrost 63:165–173
Naganuma N (1991) Mixing powder with liquid. Netsu Shori 31:95–99
Nakamura H, Watano S (2008) Fundamental particle fluidization behavior and handling of nano-particles in a rotating fluidized bed. Powder Technol 183:324–332
Nam C, Pfeffer R, Dave RN, Sundaresan S (2004) Aerated vibrofluidization of silica nanoparticles. AIChE J 50:1776–1785
Oliveira MILL, Chen K, Ferreira JMF (2002) Influence of the deagglomeration procedure on aqueous dispersion, slip casting and sintering of Si3N4-based ceramics. J Eur Ceram Soc 22:1601–1607
Park A-H, Bi HT, Grace J (2002) Reduction of electrostatic charges in gas–solid fluidized beds. Chem Eng Sci 57:153–162
Peciar M (1992) Mixing of finely powdered materials. Chem Prum 42:124–126
Pfeffer R, Davé RN, Wei D, Ramlakhan M (2001) Synthesis of engineered particulates with tailored properties using dry particle coating. Powder Technol 117:40–67
Quevedo JA, Pfeffer R (2010) In situ measurements of gas fluidized nanoagglomerates. Ind Eng Chem Res 49:5263–5269
Quevedo JA, Nakamura H, Shen Y, Davé RN, Pfeffer R, Watano S (2006) Fluidization of nanoparticles in a rotating fluidized bed. AIChE J 52:2401–2412
Quevedo JA, Flesch J, Pfeffer R, Dave RN (2007) Evaluation of assisting methods on fluidization of hydrophilic nanoagglomerates by monitoring moisture in the gas phase. Chem Eng Sci 62:2608–2622
Quevedo JA, Omosebi A, Pfeffer R (2010) Fluidization enhancement of agglomerates of metal oxide nanopowders by microjects. AIChE J 56:1456–1468
Quintanilla MAS, Valverde JM, Castellanos A, Lepek D, Pfeffer R, Dave RN (2008) Nanofluidization as affected by vibration and electrostatic fields. Chem Eng Sci 63:5559–5569
Quintanilla MAS, Valverde JM, Espin MJ, Castellanos A (2012) Electrofluidization of silica nanoparticle agglomerates. Ind Eng Chem Res 51:531–538
Ramlakhan M, Wu C-Y, Watano S, Davé RN, Pfeffer R (2000) Dry particle coating using magnetically assisted impaction coating (MAIC): modification of surface properties and optimization of system and operating parameters. Powder Technol 112:137–148
Reddy V (1989) Getting from wet to dry. Manuf Eng 102:83–86
Roco MC (1999) Nanoparticles and nanotechnology research. J Nanopart Res 1:1–6
Sanganwar GP, Gupta RB, Ermoline A, Scicolone JV, Dave RN (2009) Environmentally benign nanomixing by sonication in high pressure carbon dioxide. J Nanopart Res 11:405–419
Scicolone JV, Sanganwar GP, To D, Ermoline A, Davé RN, Gupta RB, Pfeffer R (2007) Deagglomeration and mixing of nanoparticles. Paper presented at annual PARTEC 2007 meeting, Paper 36218, Nuremburg, 12 Apr 2007
Scicolone JV, Mujumdar A, Sundaresan S, Dave RN (2011) Environmentally benign dry mechanical mixing of nano-particles using magnetically assisted impaction mixing process. Powder Technol 209:138–146
Seekkuarchchi N, Kumazawa H (2008) Aggregation and disruption mechanisms of nanoparticulate aggregates. 2. Dispersion of aggregates using a motionless mixer. Ind Eng Chem Res 47:2401–2413
Shinohara N, Dabbs DM, Aksay IA (1986) Infrared transparent mullite through densificiation of monolithic gels at 1250 degrees celcius. Infrared Opt Trans Mater 683:19–24
Siegel RW (1999) Introduction and overview. In: Siegel RW, Hu E, Reco MC (eds) WTEC panel report on nanostructure science and technology: R&D status and trends in nanoparticles, nanostructured materials, and nanodevices. Springer, New York, pp 1–14
To D, Yin X, Sundaresan S, Dave RN (2009) Deagglomeration of nanoparticle aggregates via rapid expansion of supercritical or high-pressure suspensions. AIChE J 55:2807–2826
To D, Sundaresan S, Dave RN (2011) Nanoparticle mixing through rapid expansion of high pressure and supercritical suspensions. J Nanopart Res 13:4253–4266
Uhland SA, Cima MJ, Sachs EM (2003) Additive-enhanced redispersion of ceramic agglomerates. J Am Ceram Soc 86:1487–1492
Vaizoglu O (1999) Assessment of the degree of mix of powder mixtures. Turk J Phys 23:97–104
van der Wel P (1999) Powder mixing. Powder Handl Process 11:83–86
van Ommen JR, King DM, Weimer A, Pfeffer R, van Wachem BGM (2010) Experiments and modeling of micro-jet assisted fluidization of nanoparticles. In: Kim SD, Kan Y, Lee JK, Seo YC (eds) Proceedings of the 13th international conference on fluidization. Engineering Conference International, New York, pp 479–486
van Ommen JR, Valverde JM, Pfeffer R (2012) Fluidization of nanopowders: a review. J Nanopart Res 14(3):737
Venables H, Wells JI (2001) Powder mixing. Drug Dev Ind Pharm 27:599–612
Wang Y, Gu G, Wei F, Wu J (2002) Fluidization and agglomerate structure of SiO2 nanoparticles. Powder Technol 124:152–159
Wei D, Dave RN, Pfeffer R (2002) Mixing and characterization of nanosized powders: an assessment of different techniques. J Nanopart Res 4:21–41
Yang J, Wang Y, Dave RN, Pfeffer R (2003) Mixing of nanoparticles by rapid expansion of high pressure suspensions. Adv Powder Technol 14:471–493
Yang J, Sliva A, Banerjee A, Davé RN, Pfeffer R (2005) Dry particle coating for improving the flowability of cohesive powders. Powder Technol (Special Issue in Memory of Prof. Molerus) 158:21–33
Yu Q, Dave RN, Zhu C, Quevedo JA, Pfeffer R (2005) Enhanced fluidization of nanoparticles in an oscillating magnetic field. AIChE J 51:1971–1979
Zeng P, Zhou T, Yang J (2008) Behavior of mixtures of nano-particles in magnetically assisted fluidized bed. Chem Eng Process 47:101–108
Zhu C, Liu G, Yu Q, Pfeffer R, Dave RN, Nam C (2004) Sound assisted fluidization of nanoparticle agglomerates. Powder Technol 141:119–123
Zhu C, Yu Q, Dave RN, Pfeffer R (2005) Gas fluidization characteristics of nanoparticle agglomerates. AIChE J 51:426–439
Acknowledgments
Financial support for this study was provided by the NSF-NIRT award (DMI-0506722). Additional support came through an NSF-IGERT award (DGE-0504497) as well as the NSF-NNCS Scholarship (DMI-0210400) award to JVS, and the NSF award (EEC-0540855). Thanks are due to Prof. Sankaran Sundaresan for many useful discussions and to Prof. Robert Pfeffer for insightful suggestions during the initial phase of this research. Assistance from Fernando Rivas and Dr. Daniel To is also gratefully appreciated.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Scicolone, J.V., Lepek, D., Louie, L. et al. Fluidization and mixing of nanoparticle agglomerates assisted via magnetic impaction. J Nanopart Res 15, 1434 (2013). https://doi.org/10.1007/s11051-013-1434-7
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s11051-013-1434-7