Al(III) and Cu(II) simultaneous foam separation: Physicochemical problems

Abstract

In the paper, simultaneous removal of Al(III) and Cu(II) from dilute aqueous solutions by ion and precipitate flotation methods is investigated. Influence of the pH of the initial solution, the surface active collector concentration and the gas flow rate on the final removal ratio and the course of ion and precipitate flotations is presented. The results show that simultaneous flotations of Al(OH)3 and Cu(OH)2 insoluble species occur allowing to achieve their almost complete removal in the pH range between 7 and 9. An increase of the surface active agent concentration causes a decrease of the final removal ratio as well as of the flotation rate constant. An increase of the gas flow rate results in an increase of ion and precipitate flotation rates.

Simultaneous Removal of Al, Cu and Zn Ions from Aqueous Solutions Using Ion and Precipitate Flotation Methods

“…where c 0 and c ∞ are concentrations of Al(III), Cu(II), or Zn(II) in the initial solution and in the solution when the flotation is finished (concentration does not change any further), respectively. The courses of ion and precipitate flotations were recorded as changes in temporary removal ratio (R τ ) during the flotation time (τ) [20,29,48]:…”

“…where c is the temporary concentration of Al(III), Cu(II) or Zn(II) in the solution during flotation. Based on our own as well as published experimental results [20,29,44,[48][49][50][51][52], it is known that the kinetics of ion and precipitate flotations of metal ions can be described by Equation 4, which is analogous to the first-order reaction rate equation:…”

“…It seems that an interesting aspect of the research regarding ion and precipitate flotation is related to the analysis of the conditions enabling either the simultaneous removal of several ions from a solution or the selective flotation of a target ion. However, the literature on the subject is dominated by articles describing the foam separation of single metal ions, while there are a few publications on the simultaneous ion and precipitation flotation of two or more metals [29,31,34,39]. The use of flotation techniques in wastewater treatment requires not only information about the course of the ongoing processes, but also about the possibility of its controlling.…”

A review of the applications of ion floatation: wastewater treatment, mineral beneficiation and hydrometallurgy

“…The rapid development of industry and the increasing productivity of many industrial branches have resulted in the pollution of ground water sources; thus, people worldwide face the problems of lack of fresh water together with the spread of various diseases due to organic and inorganic contaminants. 19 Sustainable development of wastewater is especially stressed because wastewater is a renewable resource from which water can be recovered for reuse. [20][21][22] Numerous methods have been developed to remove contaminants from aqueous solutions, such as chemical precipitation, oxidation or reduction, adsorption, coagulation/occulation, ltration, ion-exchange, electrochemical treatment, reverse osmosis, membrane technology, evaporation and electrootation.…”

Selective Separation of Scheelite from Calcite by Self-Assembly of H2SiO3 Polymer Using Al3+ in Pb-BHA Flotation

“…When aluminum salts enter the aqueous solution, the aluminum ions undergo a step-by-step hydrolysis reaction at pH > 3.0; at low aluminum concentrations (i.e., less than 0.001 mol/L), the majority of hydrolyzed aluminum exists as mononuclear aluminum hydroxide complexes [32][33][34][35]. The hydrolysis reactions proceed as per the equilibrium constants shown in the following equilibria [33,[36][37][38][39]:…”