Removal of total petroleum hydrocarbons from oil refinery waste using granulated NaA zeolite nanoparticles modified with hexadecyltrimethylammonium bromide

Petroleum pollution is a common problem in industrial areas to such an extent that it poses a global threat. The wastes of oil refineries contain a wide variety of hydrocarbons. The aim of this study was to investigate the possibility to removal of total petroleum hydrocarbons (TPH) from the Behregan oil refinery, Bushehr, Iran, by granulated nanozeolite NaA particles (NaA-ZNPs) modified with cationic surfactants. Synthesized NaA-ZNPs with a silica source extracted from Hordeum vulgare were granulated by an alginate granulation method and were modified by the cationic surfactant hexadecyltrimethylammonium bromide (CTAB). The CTAB-modified granulated NaA-ZNPs were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and the Brunauer-Emmett-Teller theory. Adsorption of TPH was studied using both a batch process and a continuous-flow process in a fixed-bed column. The effect of various parameters, including time, pH, adsorbent dosage, flow rate, and column height, were investigated and the results were analyzed by gas chromatography - mass spectroscopy. The efficiency of the CTAB-modified granulated NaA-ZNPs was evaluated with one-way analysis of variance software SPSS 21. The highest TPH removal efficiency for batch processing (92.3%) was achieved at an adsorbent dosage 0.5 mg, pH = 7, and 20 min of contact time; the highest TPH removal efficiency for continuous processing (87.4%) was achieved at 15 cm column height and a 17.26 mL/min flow rate. The results indicated the potential of CTAB-modified granulated NaA-ZNPs for absorbing TPH in treating oil refinery waste.