Biosorption of food dyes onto Spirulina platensis nanoparticles: Equilibrium isotherm and thermodynamic analysis

Abstract

The biosorption of food dyes FD&C red no. 40 and acid blue 9 onto Spirulina platensis nanoparticles was studied at different conditions of pH and temperature. Four isotherm models were used to evaluate the biosorption equilibrium and the thermodynamic parameters were estimated. Infra red analysis (FT-IR) and energy dispersive X-ray spectroscopy (EDS) were used to verify the biosorption behavior. The maximum biosorption capacities of FD&C red no. 40 and acid blue 9 were found at pH 4 and 298 K, and the values were 468.7 mg g(-1) and 1619.4 mg g(-1), respectively. The Sips model was more adequate to fit the equilibrium experimental data (R2>0.99 and ARE<5%). Thermodynamic study showed that the biosorption was exothermic, spontaneous and favorable. FT-IR and EDS analysis suggested that at pH 4 and 298 K, the biosorption of both dyes onto nanoparticles occurred by chemisorption.

Biofortification of maize with micronutrients by Spirulina

“…It was proved that high yields can be produced using desalinated wastewater and animal manure [17]. Annual worldwide production is about 2000 tons [18]. Algal biomass can be used as a biosorbent material because is available in large quantities, its processing is relatively cheap and have gives good performance at low cost [19].…”

Removal of FD&C Red No.40 Food Dye from an Aqueous Solution by Vine-Trimming Waste

“…These include a large variety of methods such as flocculation, precipitation, filtration, flotation, membrane filtration, ozonization, oxidation, ion exchange, coagulation and adsorption that are used in various industries [3]- [7]. Of these methods, adsorption stands out as a more advantageous method compared to the others for treating industrial waste water as it is economical and takes into account environmental concerns.…”

Hydrophobic Organosilica Adsorbents for Removal of Sodium Diclofenac From Aqueous Solutions

“…Blanks were run in parallel and corrected when necessary [1,5]. The solutions of DCF were stored in glass bottles, which were cleaned by immersing in 1.4 mol L -1 HNO3 for 24 h [1,5], rinsing with deionized water, drying and keeping them in cabinets. Standard DCF solutions (5.00-50.00 mg L -1 ), which is in parallel with a blank, were used for linear analytical calibration.…”

“…Nonlinear methods with successive interactions calculated by the LevenbergMarquardt method were used to fit the kinetic and equilibrium data. A determination coefficient (R 2 ), an adjusted determination coefficient (R 2 adj ) and the Ferror were employed to analyze the suitability of the models [1,5]. The R 2 , R 2 adj and F error are given in Eqs (3), (4) and (5), respectively.…”

“…In these equations, q i, model represents individual theoretical q value predicted by the model; q i,exp represents individual experimental q value; exp q is the average of experimental q values; n represents the number of experiments; p represents the number of parameters in the model [1,5]. …”