Dynamically formed membranes

Supported Tube. There are three types of supported tubular membranes cast in place (integral with the support tube), cast externally and inserted into the tube (disposable linings), and dynamically formed membranes. 

Dye wastewater, 9 431 Dynamic affinity chromatography, 6 398 Dynamic allotropy, 23 564 Dynamically formed membranes, 15 813t Dynamic coefficient, 15 205 Dynamic compressors, in refrigeration systems, 21 535... 

The layers deposited on the membrane during cross-flow microfiltration are sometimes thought to constitute dynamically formed membranes with their own rejection and permeation characteristics. 

Besides the synthesis methods for porous membranes and their modification methods discussed above, other synthesis methods have been reported. These are outlined below. Preparation of dense membranes is discussed in Section 2.2. The other types are the so-called dynamically formed membranes which... 

Dynamically formed membranes were pursued for many years for reverse osmosis because of their high water fluxes and relatively good salt rejection, especially with brackish water feeds. However, the membranes proved to be unstable and difficult to reproduce reliably and consistently. For these reasons, and because high-performance interfacial composite membranes were developed in the meantime, dynamically formed reverse osmosis membranes fell out of favor. A small application niche in high-temperature nanofiltration and ultrafiltration remains, and Rhone Poulenc continues their production. The principal application is poly(vinyl alcohol) recovery from hot wash water produced in textile dyeing operations. 

Dynamically formed membranes Zr02/po1yacryi ic acid Polyacryllc acid Oak Ridge Nat. Lab. UNIV. Oil Prod (Gulf) 5000 2000 90 80 70 102 0.3 0.3 ... 

Colloidal oxides filtered through microporous supports typically give rise to "Class II" dynamically formed membranes, whose formation mgchanlsm characteristics and properties have been reviewed —. The most important relations are ... 

B. Si02 Dynamically Formed Membranes. The procedures and equip-... 

Of course, these results are for pure water and when the unit is used with a dynamically formed membrane, the increased membrane resistance does not allow us to draw such high absolute values of Qp. However, the Important point is that the ratio of flows required to achieve turbulence in the channel will not change significantly and thus the overall module efficiency can be expected to remain at a high value. 

The general properties of representative dynamically-formed membranes axe provided in Table I. 

Dynamically formed membranes A colloidal material is added to the feed solution of an ultrafiltration membrane. A gel forms on the membrane surface and enhances the membrane selectivity 43,44... 

Resting, R. E., Synthetic Polymeric Membranes A Structural Perspective , 2nd edn., Wiley-Inter-science. New York, 1985. Membrane types are emphasized—polymer membranes, the polymeric films, phase inversion membranes, liquid and dynamically formed membranes, biological membranes. 

Dynamically formed membranes were first investigated in 1997 using monolayer of PA A (a weak acid polyelectrolyte) that was deposited on a macroporoustitania layer sintered on the inside of a porous stainless steel tubular module (Xu and Spencer 1997). This work used the produced membrane to investigate the separation of Cibacron blue (a kind of dye) from NaNOj. It was found that the separation factor... 

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