Surface pretreatments high-energy surfaces

Convenience membrane replacement and easy cleaning of surface contamination High energy consumption per unit amount of liquid treated High feed flow rate helps reduce the membrane contamination Low packing density of the module Simple pretreatment of feed liquid... 

An electromagnetic field at high energy ionises the air in the enviromnent and this generates chemically active species. Corona pretreatment provides a limited activation of the substrate surface to achieve an optimal bonding. 

Following such a pretreatment, a controlled, high-energy film of active, aluminium oxide/hydroxide , eminently suitable for structural bonding, will have been grown on the surface of the aluminium. The oxide film can be seen in Fig. 5 at the interface between the alloy and the adhesive. It is a needle-Uke structure growing from the underlying aluminium substrate and has a thickness of about 300 A. It is clear that the adhesive completely wets and penetrates this surface. 

Following such a pretreatment, a controlled, dense, high energy film of active aluminium oxide/hydroxide will have been grown on the surface of the aluminium. The film thickness will be in the region of 3-4 p.m. 

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