Adsorptive behaviour of surface tailored fungal biomass for the elimination of toxic dye from wastewater

ABSTRACT

In the present research, adsorptive separation of Reactive Red-3 (RR3) from aqueous solution has been studied using surface tailored fungal biomass (Trichoderma harzianum). SEM with EDAX, XRD, FTIR and TG-DTA of the adsorbent had been discussed to verify the quality and efficiency of the adsorbent. The dye solution pH of 4, biosorbent dosage (0.5 g/L), contact time (150 min) and incubation temperature (40°C) for an initial dye concentration of 100 mg/L were predicted as an optimum condition for the highest removal of dye from aqueous solution. Among various kinetic models analysed, pseudo-second order model explains well the adsorptive cycle with a comprehensive relationship between experimental and measured biosorption capacity. Removal data was also analysed by using Langmuir, Dubinin–Radushkevich, Freundlich and Temkin isotherms. The process of biosorption was well described by Freundlich isotherm because of the higher correlation coefficient. The results of the models have been used to determine the ideal mechanism of the biosorption process. Langmuir sorption capacity was estimated as 172.63 mg/g at an optimum condition. Thermodynamic studies were also analysed to evaluate the parameters such as change in enthalpy (28.982 kJ/mol), change in Gibbs free energy and change in entropy (116.56 J/mol K), which indicates that the biosorption process was spontaneous at all temperatures and endothermic in nature. The prepared material can be an alternative to the existing biosorbents.

KEYWORDS:

• Toxic dye
• Trichoderma harzianum
• biosorption
• isotherm
• kinetics
• thermodynamics

Disclosure statement

No potential conflict of interest was reported by the author(s).