Performance evaluation of polymer-marine biomass based bionanocomposite for the adsorptive removal of malachite green from synthetic wastewater

In this experimental investigation, feasibility and performance of a polymer hybrid bio-nano composite were evaluated to remove malachite green (MG) under controlled environment conditions. The polymer hybrid bio-nanocomposite was characterized using FTIR, SEM and EDS. The influence of operating variables, namely effect of pH (2–11), nanocomposite dosage (20–100 mg), initial MG concentration (10– 200 mg/L), contact time (10–120 min) and temperature (298–318 K) were explored. The maximum removal efficiency (RE) of 99.79% was achieved at neutral pH at the dosage level of 50 mg with the initial MG concentration of 150 mg/L in 40 min. The equilibrium results revealed that the adsorption of MG data fitted to Langmuir isotherm (R2 > 0.970) indicating monolayer adsorption. The maximum adsorption capacity of polymer hybrid nanocomposite was found to be 384.615 mg/g. Kinetic studies were performed using five kinetic models and results showed the pseudo second order model fitted very well with the MG adsorption data (R2 > 0.990). The thermodynamic results confirmed that MG adsorption onto polymer hybrid nanocomposite is feasible and (ΔS ͦ = 0.2893 kJ/mol K), spontaneous (ΔH ͦ = 81.103 kJ/mol K) and exothermic (ΔG ͦ