How to avoid contamination of cations anions in surface treatment processes

摘要

Because of the environmental impact of the production of toxic by-products from surface treatment processes, the European Union required an exhaustive study for the optimization, minimization and recovery of those products to avoid damage to the environment. The EU requires a complete study of processes and intermediate reaction stages in order to grant the ecological label (which is the symbol ∈ and a daisy). The subsequent treatment for toxic waste products is done in physical-chemical purifying plants, physical-chemical biological plants, evaporators, resin interchange, water recovery, and zero discharge systems This is aimed to optimize and avoid discharging cations of Ni; Cr, Ad, Sn, Pb and anions of (NO{sub}3{sup}-SO{sup}(-4), CO{sub}3, PO{sub}4, etc. During surface treatment processes, discharging has to be studied to avoid contamination and secondary reactions than can be produced after neutralizing, 4estruction, oxidation or reduction of cations and anions.