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The possibility of recovering one of the famous heavy metal ions, divalent copper, from contaminated aqueous solutions (which simulates wastewater) was studied in this study. The removal method was adsorption technique using a laboratory batch-mode unit, while the used tea leaves were the adsorption media. The adsorption process was performed under various operating conditions and ranges that simulate the natural environmental conditions to determine the ideal values that achieve the maximum removal of copper ions. The acquired results demonstrated that the maximum remediation eficiency was 85%, which was achieved at treatment time, shaking speed, initial concentration, temperature, acid function, and adsorption dose of 90 min, 250 rpm, 70 ppm, 25oC; 4; 4:5g, respectively. The values of the thermodynamic properties demonstrated that adsorption is spontaneous, exothermic and has negative entropy, while adsorption follows Langmuir's model and the second pseudo-model according to the isotherm and kinetic studies, respectively. To conduct the Zero Residues Level concept, the loaded used tea leaves were prepared to study it effect as a simple type of rodenticide by applying it to Sprague Dawley rats. The results of the test show that the effectiveness of utilizing the residues as rodenticide and the Half lethal dose LD50 of the proposed rodenticide were identical to those mentioned in the literature. Based on these results, the current study sheds light on the possibility of converting used tea leaves from harmful solid waste to an environmentally friendly substance using it as an effective adsorbent medium for the treatment of water polluted with heavy metals. [ABSTRACT FROM AUTHOR]

In this study, pyrolysis of shredded waste tire was carried out thermally and catalytically in a fixed bed reactor. Thermal pyrolysis was performed at temperatures of 330 °C, 430 °C, 530 °C, and 630 °C under Ar. flow rate of 0.5 L/min as a carrier gas and retention time of 15 min catalytic pyrolysis was carried out at temperature of 530 °C. The effects of temperature and two types of catalysts (CaCO3 and SiO2/Al2O3) were studied on the yield of pyrolysis products. Fourier transform infrared spectroscopy (FTIR) and Gas chromatography mass spectrometry (GC-MS) analysis for the oil products that were obtained by thermal and catalytic pyrolysis at 530 °C for chemical characterization. Oil, solid, and gas products yield by thermal pyrolysis at 530 °C were 50 wt. %, 35.6 wt. %, and 14.4 wt. % respectively, when the CaCO3 catalyst was used, the products distribution was 52 wt. %, 38.5 wt. %, and 9.5 wt. % respectively. While using SiO2/Al2O3 the pyro oil, and char, and gas were decreased to 47 wt. %, 38 wt. %, and 15 wt. % respectively. The chemical composition of pyrolysis oil mainly included hydrocarbons compounds, predominantly Limonene which was represented by Cyclohexene, 1-methyl-4-(1-methylethenyl). [ABSTRACT FROM AUTHOR]