Micro fluidizer

Jafari SM, He YH, Bhandari B (2006) Nanoemulsion production by sonication and micro-fluidization - a comparison. Int J Food Prop 9 475-485... 

The following protocol, which is derived from the one-step liposome preparation technique, originally described in (12) is suited. A slurry is made from a single phospholipid or a freeze-dried cake of lipid-blend and buffer (drug/marker solution). The slurry is processed using an APV MicronLab 40 lab-scale homogenizers. A micro-fluidizer Ml 10 may be used as well. 

Styrene SLS/CA Micro- fluidizer K2S2O8 70 20 PSD evolution monitored nucleation period past rate maximum [14] Miller et al. 1994... 

VAc, V2EH VAC/V2EH TREM LF-40/HD Micro- fluidizer Na2S208 60 20 Rp (mini) > Rp (conv.) effect of reactive surfactant [16] Kitzmiller et al., 1994... 

Styrene SLS/CA, SLS/HD Micro- fluidizer K2S20g 70 20 Broad PSDs (CA) < k, (HD) CA acts as chain transfer agent [9] Tang et al., 1992... 

Tan L, Roghair I, Van Sint Atinaland M Simulation study on the effect of gas permeation on the hydrodynamic characteristics of membrane-assisted micro fluidized beds, Appl Math Model, 2014. http //dx.doi.Org/10.1016/j.apm.2014.04.044 (in press). 

Wang J, Tan L, van der Hoef MA, van Sint Annaland M, Kuipers JAM From bubbling to turbulent fluidization advanced onset of regime transition in micro-fluidized beds, Chem Eng Sd 66 2001-2007, 2011. 

Micro- fluidization Continuous TI,TV Medium-High 1 0 -2 X 10 High <0.1 j,m Low-medium... 

Chadonnet, S., H. Korstredt, A. Siciliano, Preparation of microemulsions by micro-fluidization, Soap/Cosmet./Chem. Specialties, 61, 2, p. 37, 1985. 

As mentioned in Section 2.2 (Fixed-Bed Reactors) and in the Micro activity test example, even fluid-bed catalysts are tested in fixed-bed reactors when working on a small scale. The reason is that the experimental conditions in laboratory fluidized-bed reactors can not even approach that in production units. Even catalyst particle size must be much smaller to get proper fluidization. The reactors of ARCO (Wachtel, et al, 1972) and that of Kraemer and deLasa (1988) are such attempts. 

For ethanol production a substantial improvement over the packed bed reactor is offered by the gas-solid fluidized bed fermenter which uses a liquid instead of a solid substrate and replaces the packed bed of substrate or micro-organisms with a fluidized bed of yeast pellets (Smith et al, 1997). This system can be viewed as a standard fermentation against which the performance of different bioreactors may be assessed. 

The advantages of fluidized beds compared to fixed bed reactors are improved heat and mass transfer, an easier passage through the bed for foreign material and unwanted micro-organisms, a lower pressure drop, better control of the thickness of the biofilm and the easy removal of particles from the bed in order to remove excess biomass (Epstein, 2003). 

Studies at Mobil Research have shown that light olefins instead of gasoline can be made from methanol by modifying both the ZSM-5-type MTG (Methanol-to-Gasoline) catalyst and the operating conditions. Work carried out in micro-scale fluidized-bed reactors show that methanol can be completely converted to a mixture of hydrocarbons containing about 76 wt% C2-C5 olefins. The remaining hydrocarbons are 9% C1-C5 paraffins, of which the major component is isobutane, and 15% C6+, half of which is aromatic. 

For multiphase flow that is normally encountered in fluidized bed reactors, there are two kinds of definitions of the micro-scale first, it is the scale with respect to the smaller one between Kolmogorov eddies and particles second, it is the scale with respect to the smallest space required for two-phase continuum. If the first definition is adopted, the... 

Xia, Y., and Kwauk, M., Micro-Visualization of Fluidizing Behavior of Binary Particle Mixtures," Intern. Symp. Heat Transfer, Beijing, 1985, Hemisphere (1985). 

To account for the intrinsic characteristics of particle-fluid two-phase flow in fast fluidization, the particles and the fluid are considered to interact with each other on both a micro-scale and meso-scale level to produce local or meso-scale heterogeneity (phases), and the overall fluid-particle system interacts with the equipment boundaries on a much larger scale to produce macro-scale heterogeneity (regions). 

In effect, such a multi-scale analysis resolves a macro-scale heterogeneous system into three meso- to micro-scale subsystems—dense-phase, dilute-phase and inter-phase. Thus, modeling a heterogeneous particle-fluid two-phase system is reduced to calculations for the three lower-scale subsystems, making possible the application of the much simpler theory of particulate fluidization to aggregative fluidization and the formulation of energy consumptions with respect to phases (dense, dilute and inter) and processes (transport, suspension and dissipation). 

Fluidization quality in terms of material properties, particle characteristics, and particle group behavior thus needs to be assessed on three scales gross scale of the fluidized bed (macro scale), aggregate scale of gas bubbles, and particle clusters (meso scale), and scale of the discrete, individual particles (micro scale), as described in Chapter 4. 

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