Jornal de Ciência e Tecnologia de Membranas

Abstrato

Performances of Continuous Adsorption-Ultrafiltration Hybrid Process for AO7 Dye Removal from Aqueous Solution and Real Textile Wastewater Treatment

Ahmed Hammami, Cahtherine Charcosset and Raja Rekik Ben Amar

A hybrid treatment combining the adsorption by PAC with Ultrafiltration (PAC-UF) was applied to the color removal from Acid Orange 7 (AO7) aqueous solutions. The effect of different parameters on color removal and permeate flux evolution such as dose of PAC, pH, TMP and adding of surfactants, was studied. The best operating conditions for a total removal of color were 3 bar TMP, 5 pH, and dose of PAC beyond 150 mg/L in presence of cationic surfactant. A constant permeate flux was observed for all the tests. The evolution of the permeate flux with time can revealed the formation of a PAC-dyes layer due to the retention of these particles by UF membrane. The AO7 not adsorbed by PAC cannot be removed by UF alone. The application of hybrid treatment reduced the UF membrane fouling and the dose of PAC. Permeate flux was then increased from 340 L/h.m² (only UF) to 480 L/h.m² (PAC-UF) and PAC dose was reduced from 300 mg/L to 150 mg/L when adsorption followed by UF treatment applied in two stages was changed to a single stage PAC-UF hybrid process. Applied to real waste water treatment coming from textile company using reactive dyes, the results with the continuous hybrid adsorption/UF over a period of three hours were in agreement with those obtained with the aqueous dyeing solution in terms of permeate flux and color removal behavior. In this case, a quasi-stabilize permeate flux of an average value of 450 L/h.m² and a color removal of 97% were recorded.