A low-cost nano-particle material was successfully prepared using waste pomegranate peels. Batch adsorption experiments were carried out to investigate the effect of different operating conditions on the removal of brilliant green (BG) dye from an aqueous solution. SEM images of pomegranate peels nano-particles (PPNP) declared roughness of the surfaces and TEM images indicated a spheroid shape with an average particle size of 37 nm. The specific surface area of the PPNP was 354.46 m2/g and the particle size had a mean diameter of 613.4 nm. The active nano-particle suspension showed a net negative charge (-29 mV) at natural pH. The XRD pattern of PPNP displayed an average crystallite size of 13.50 nm and EDS analysis shows that the PPNP consists of 83% carbon. The experimental work showed that the removal of BG had optimum removal efficiency at 20 min, 0.3 g adsorbent mass, 25 °C, and pH 8. The kinetic data can be described well with the pseudo-second-order model and the isotherm data was found to fit the Dubinin model. The thermodynamic study proved that BG adsorption on PPNP was physisorption (ΔG = -5.949 kJ/mol) and spontaneous at low temperature (ΔH = -17.193 kJ/mol, ΔS = -0.0382 kJ/mol. k)This study used an agriculture waste (pomegranate peels) to prepare an environmentally friendly and low-cost adsorbent within the nano-scale by thermal activation. The nano-particles prepared were shown to be a promising adsorbent, demonstrating high surface area and well-developed porosity. The prepared adsorbent will have a great impact on wastewater treatment technology and possible applications at a large scale.
Keywords: Brilliant green; characterization; nano adsorbent; pomegranate peels; preparation; wastewater.