Flocculation applications

Flocculation. The interaction of the cationic PEIs with anionic substrates leads to substrate flocculation. Applications of this property include the coagulation of latex (434), commercial application in effluent treatments (435—437), and stabilization of highly loaded coal—water mixtures in mining... 

Another aspect is that modem elastomer parts are made of a wide variety of elastomer types and/or are combined with metals or other plastics in material composites for the purpose of realizing additional functions such as sensory aspects, insertions, strength elements, textiles attached by gluing or vulcanization, lubricant coatings, installation elements, flocculation applications, paint coats, etc. 

It was anticipated by von Smoluchowski that Brownian diffusion is not the only mechanism by which one particle can come into contact with another. There can be convection in the system as well. Convection aids flocculation when it enhances the relative velocity between nearby particles, making it easier for them to surmount the maximum in the potential energy curve and reach the primary minimum corresponding to flocculation. Application of a velocity gradient (shear) is especially effective in the flocculation of relatively large particles (Hiemenz and Rajagopalan, 1977 Zeichner and Schowalter, 1977, 1979). It can also break up floes associated with the secondary minimum of the particle interaction curve (Zeichner and Schowalter, 1977, 1979). 

Abstract This review concentrates on the interactions between oppositely charged polyelectrolytes and on the formation of complexes, which can be used for different applications such as paper retention or water treatment. Three different possibilities for the appearance of polyelectrolyte complexes (PECs) in flocculation applications are described. Starting with the classical dual system (step-by-step addition of polycation and polyanion to a negatively charged suspensimi of fibers or particles), the interaction between a soluble polyanion (such as anionic trash) with polycation is described as well as the formation of well-defined pre-mixed PECs and their application as flocculants. 

There are some different possibilities for the appearance of PECs in flocculation applications. The most important options are presented in Eig. 1. 

Fig. 1 Different types of polyelectrolyte complexes (PECs) in flocculation applications...

But, in the meantime, the importance of flocculation applications has been growing because of increasing requirements in several fields, such as for ... 

Polyelectrolyte Complexes in Flocculation Applications Table 2 (continued)... 

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