Removal of Copper(II) from Aqueous Solutions by Biosorption-Flotation

Abstract

This study investigates the removal of Cu(II) from aqueous solutions by biosorption-flotation as a function of several parameters, such as collector type, pH, molar ratio, air pressure, time, and initial metal concentration. Dissolved air flotation was applied as a polishing technique for the additional purification of the effluent resulted after biosorption. The obtained results were supported by the physicochemical characteristics of the surfactants used as flotation reagents and suggested that cetylpyridinium bromide (CPB) was the optimum collector for Cu(II) ion removal. Cu(II) removal efficiency exhibited a maximum of 97.09 % in the following operating conditions: biosorption pH 4.5, Cu(II) initial concentration 250 mg/L, biosorbent dosage 0.5 %w/v, agitation rate 200 rpm, temperature 20°C, biosorption time 30 min, flotation pH 9, air pressure 4.5×10 5 Pa, dilution ratio 3:1, flotation time 10 min, collector CPB 0.01 M, and molar ratio collector/ Cu(II) 5×10 −1 :1. The experimental data confirmed that the flotation stage contributed to the optimization of the overall separation process.

Research Activities Related to Flotation Process

“…Cu 2+ removal from aqueous systems, by combining biosorption onto inactive dry baker's yeast Saccharomyces cerevisiae with dissolvedair flotation, was investigated [12]. The obtained results were supported by the physicochemical characteristics of the surfactants used as flotation reagents.…”

A review on adsorbents used for defluoridation of drinking water

“…The lower removal rate at acidic pH (3-5) may be due to the formation of weak hydrofluoric acid. Acidic alumina, KMnO 4 modified activated carbon, FeO(OH) and alkoxide origin alumina showed maximum fluoride removal capacity in acidic pH, since the surface of the adsorbent is highly protonated (Goswami and Purkait 2012;Daifullah et al2007;Stoica et al 2012;Kamble et al 2010). The high removal at acidic pH is due to a greater increase in the attractive force between positively charged surface and negatively charged fluoride ions.…”

“…Langmuir isotherm model fitted the best and the sorption capacity was found to be 242.2 mg/g at pHeq B 7.5 and 24.8 mg/g at pHeq [ 10.0. The efficiency of FeO(OH) in removing fluoride from aqueous environment was examined by Stoica et al (2012). Its granular structure, high surface area and effective capacity of fluoride removal make this adsorbent a highly potential media to be used in removing the fluoride from aqueous systems.…”