Nowadays, advanced oxidation processes, particularly photocatalyst process and catalytic ozonation by ZnO nanoparticles, are the most efficient method of eliminating pharmaceuticals. The purpose of this study was to compare the efficiency of ultraviolet/zinc oxide (UV/ZnO) and ozone/zinc oxide (O₃/ZnO) techniques as advanced oxidation processes in the removal of trimethoprim (TMP) from aqueous solutions. The process consisted of 0.6g/L of ozone (O₃), pH=7.5±0.5, TMP with a concentration of 0.55mg/L, ZnO with a dose of 50500mg/L, 530min reaction time, and 30180min contact time with UV radiation (6W, 256nm) in a continuous reactor. The high removal efficiency was achieved after 25 minutes when ZnO is used in 1mg/L TMP under an operational condition at pH 7.5. When the concentration of the pollutant increased from 0.5 to 1, the average removal efficiency increased from 78 to 94, and then, it remained almost constant. An increase in the reaction time from 5 to 25 minutes will cause the average elimination to increase from 84 to 94. The results showed that the efficiency of O₃/ZnO process in the removal of TMP was 94, while the removal efficiency of UV/ZnO process was 91. The findings exhibited that the kinetic study followed the second-order kinetics, both processes. With regard to the results, the photocatalyst process and catalytic ozonation by ZnO nanoparticles can make acceptable levels for an efficient posttreatment. Finally, this combined system is proven to be a technically effective method for treating antibiotic contaminants.

This study aims to investigate the biosorption of Pb (II) by living and nonliving biomass of Penicillium notatum. Penicillium notatum PTCC 5074 was purchased from Iran Scientific-Industrial Research Organization in lyophilized form and after culturing in potato dextrose agar was propagated in Sabouraud dextrose broth medium. The highest adsorption by living and nonliving biomass (180.74 and 187.08mg/g per dry weight of biomass, respectively) was at the Pb (II) concentration of 228mg/L and ionic strength of 43mg/L in terms of Ca²⁺ and 1.2g/L biomass concentration. The optimum contact time and temperature in nonliving biomass were 37 hours and 32.5°C, respectively. Kinetic studies showed that Pb(II) adsorption in both cases follows a pseudo-second-order reaction. The adsorption process was consistent with the Langmuir model in the nonliving state, whereas the favourite models for the living state were Langmuir and Freundlich. Thermodynamic constants indicated that the adsorption process by nonliving and living biomass were exothermic and endothermic, respectively. The obtained results showed that Penicillium notatum in living and nonliving states is suitable for the development of an efficient and economic biosorbent for the removal of Pb (II) from aqueous environments.