Critical environmental issues have emerged from wastewater of industrial textile effluent discharge which consists of refractory dyes. Effective methods such as activated carbon (AC) adsorption is extremely demanded for solving this environmental pollution. In this study, low-cost AC was developed from Parkia speciosa pods (PSP) using microwave-assisted activation technique for the methylene blue (MB) dye adsorption. Optimization on activating conditions in terms of MB removal and AC yield was performed using response surface methodology (RSM). The optimum microwave irradiation power (MIP) of 416.50 W was found to have significant effect on MB removal at 2 minutes activation. The Parkia speciosa pods activated carbon (PSPAC) possessed intermediate surface area and total pore volume of 51.3 m2/g and 0.0681 cm3/g, respectively. PSPAC surface morphology was microscopically observed with highly porous structure indicating characteristics of good AC. Batch adsorption studies with various initial concentrations discovered that MB adsorption increased with increasing initial concentrations and contact time. The experimental data was in close fit using Langmuir isotherm and followed pseudo-first-order kinetic models. The MB dye adsorption process was governed by simultaneous surface adsorption and intraparticle diffusion. The results of studies proved that PSPAC is a potential adsorbent for dye-contaminated wastewater.
