Removal of Direct Red from Aqueous Solution by Foam Separation Techniques of Ion and Adsorbing Colloid Flotation

Removal of color from textile dyeing wastewater by foam separation

“…The reasons for this were: firstly, direct dyes anions were protonated, which made the formation of dye-surfactant aggregate difficult [27]; secondly, lower pH induced the decrease of foam quantity and foam stability due to decreased surface tension and viscosity of the solution. We also observed lower color removal in alkaline conditions which agreed with Choi and Choi [18]. It was thought that the presence of excessive OH − competed with the direct dye anions for CTAB.…”

“…Kabil and Ghazy [17] be floated. Choi and Choi [18] studied the removal of Direct Red from aqueous solutions by using foam separation techniques of ion and adsorbing colloid flotation. Horng and Huang [19] investigated foam separation of Direct Blue 1 from simulated wastewater; over 98% of Direct Blue 1 was removed in 5 min.…”

Sustainable Wastewater Treatment via Dye–Surfactant Interaction: A Critical Review

“…In recent years, foam separation is being considered as a promising separation technique to separate surface-active materials based on the differences in their surface activity. Several reports described it as an effective and low-cost wastewater treatment method for the removal of dyes, proteins, organic materials, metal ions and even materials that are not surface-active. − Foam is usually generated by bubbling gas, in most cases air, through the aqueous wastewater and can be easily separated from the top of the solution . A surfactant, commonly known as collector, is used to make the foam stable when aerated as well as to promote the formation of dye–surfactant complexes by electrostatic interaction.…”

Motor oil removal from water by continuous froth flotation using extended surfactant: Effects of air bubble parameters and surfactant concentration

“…It was first used in ore processing, and has been pointed out to be a promising technique for oily wastewater treatment [3][4][5][6][7][8][9][10][11][12]. The froth flotation process is suitable for treating wastewater containing suspended solids as well as oils, in both emulsion and dissolved forms, because of several advantages, including rapid operation, low space requirements for equipment set-up, high removal efficiency, flexibility of the application to various pollutants at varying scales, and a low operating cost [13]. In a froth flotation operation, oily wastewater and a surfactant solution with a proper concentration are continuously fed to a froth flotation column, and air is introduced into the system in order to generate fine bubbles.…”