Adsorption of naphthalene from vehicle-wash wastewater using eucalyptus wood waste derived biochar.

This article describes the production of eucalyptus wood waste biochar (EWB) and its use in the adsorptive removal of naphthalene (Nap) from vehicle wash wastewater (VWW). EWB was produced by carbonizing the waste eucalyptus wood at a high temperature in a nitrogen atmosphere. The produced EWB was chemically activated by being subjected to 1 M HCl in order to increase its effectiveness. The EWB was described using pertinent instrumental techniques such as surface area analysis, Fourier-transform infrared spectroscopy, and scanning electron microscopy. Nap adsorption from aqueous solutions through EWB was examined using batch adsorption tests. As adsorption parameters, initial EWB concentration, contact time, pH, temperature, and adsorbent dose were all examined. Under ideal conditions, the adsorption efficiency was computed and the Nap contents were determined using a UV spectrometer. The optimal conditions for the highest adsorption of Nap from VWW on the EWB adsorbents were found to be an initial concentration of 30 ppm, contact time of 90 min, temperature of 60°C, adsorbent dose of 0.30 g, and 5 pH. Kinetic and isotherm models were applied to evaluate the adsorbent capacity to bind Nap. The kinetic study shows that the adsorption of Nap onto EWB is controlled by pseudo-second-order kinetics. The results of the experiment demonstrated that the Langmuir isotherm model offered the best fit for the data. The values of thermodynamic parameters such as entropy (Î"S°), Gibb's free energy (Î"G°) and enthalpy (Î"H°) show that the adsorption process is spontaneous and exothermic in nature. The trial results revealed that the highest adsorption at optimum condition for Nap from VWW was 98.65% (qe = 141.52 mg/g). The performances of certain commercial adsorbents utilized in practice were also compared with the results. This analysis showed that the new EWB has a significant potential (>95%) for removing and recovering Nap from industrial effluent. [ABSTRACT FROM AUTHOR]