Surface encapsulation

Major categories of industrial waste solidiflcation/stabilization systems are cement-based processes, pozzolanic processes (not including cement), thermoplastic techniques, organic polymer techniques, surface encapsulation techniques, and self-cementing techniques (for high calcium sulfate sludges). Vitrification (discussed previously) can also be considered a solidification process. 

Applicability Surface encapsulation (macroencapsulation) is appropriate for both organic and inorganic wastes. 

Advantages Major advantages of an encapsulation process involve the fact that waste materials never come into contact with water, therefore, soluble materials (such as sodium chloride) can be successfully surface-encapsulated. The impervious jacket also eliminates all leaching into contacting waters as long as the jacket remains intact. 

Corrective Action Application TRW Corporation has developed one type of encapsulation system (U.S.EPA 1980). The TRW surface encapsulation requires that the waste material be thoroughly dried. The dried waste is stirred into an acetone solution of modified... 

Exhaustive silanization with the most active of silanizing reagents cannot eliminate completely all silanol groups on the i silica surface. Encapsulating the deactivated surface by, ... 

Carbon and Phosphorus Burial Efficiencies. The estimate of diatom carbon demand (12-15 g/m2 per year) is consistent with the flux of carbon to the sediment surface. With sediment-trap fluxes corrected for resuspension, we measured a total annual deposition flux of 12.5 g of C/m2. In comparison, Eadie et al. (24) obtained 23 g of C/m2 for a 100-m station, based on three midsummer metalimnion deployments. Of our total, 83% of the carbon was associated with diatoms, and the primary diatom carbon flux was 10.3 g of C/m2. Thus, about 15-30% of the diatom carbon was regenerated in the water column during sedimentation. Approximately 10% of the diatom flux reached the sediment surface encapsulated in copepod fecal pellets the remaining 90% was unpackaged. 

Materials with inorganic or porous hydrophobic or (less frequently) hydrophilic organic polymer matrices and graphitized carbon are stable over a broad pH range from 0 to 12-14 hence, they are useful for separations of basic compounds. RP phases on aluminium and zirconium oxide supports exhibit hardness and mass transfer properties comparable to silica, and can be prepared by forming a cross-linked polystyrene, polybutadiene, or alkylated polymethylsiloxane layer on the support surface to which alkyls are attached. The inorganic surface, encapsulated by a nonpolar stationary phase, does not come into contact with the mobile phase or with the analyte, so these materials can be used in the pH range 1-14. 

The rule, therefore, is that silicone coatings are a very effective way to avoid damage to die surfaces encapsulated in epoxy transfer molding compounds provided that ... 

Zhang J. L., Srivastava R. S, and. Misra R D. K (2007). Core-Shell Magnetite Nanoparticles Surface Encapsulated with Smart Stimuli-Responsive Polymer Synthesis, Characterization, and LCST of Viable Drug-Targeting Delivery System, Langmuir, Volume 23, Issue 11, pp 6342-6351. 

Cast Polymer Solid Surface/Encapsulating/Potting Composites Continuous Panel/Electrical Liuninates/General Molded Products/RTM (Resin Transfer Holding)/SMC/BMC... 

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