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Neutral polyethylene oxide with a cofactor recommended for particle flocculation

Conventional and neutral high molecular weight polyethylene oxide (PEO) adsorbs on some colloids and fines, flocculating them into flocs. Addition of a cofactor (CF) makes PEO adsorb on all types of colloids and fines, flocculating them into larger flocs. Homoflocculation of fines with PEO alone and with CF added prior to PEO were investigated in this work at low and high effective shear rates. CF role was investigated: it enhanced flocculation amplitude and rate by several magnitudes relative to PEO used alone, and was ascribed to the CF action to stiffen and extend PEO coils. Considering CF-PEO abilities in homoflocculation and in heteroflocculation as recorded in the literature, combination of homo - and heteroflocculation can now be applied to processes. Formed flocs and individual particles will simultaneously deposit onto fibers and, when filtered, particles will be retained in the fiber cake. This technique can be applied in industry processes and water treatment.

Polyethylene oxide; Cofactor; Fines; Flocculation; Dispersion; Shear rate


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