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In this study, the reduction chemical oxygen demand (COD) in water-based paint wastewater using commercial activated carbon, activated date pits and rice husks was investigated. The process was studied in the batch mode with respect to the initial pH, contact time, and adsorbent dose. Adsorption equilibrium and kinetic data were determined for the three adsorbents and were fitted to several isotherm and kinetic models accordingly. The results indicated that activated rice husks (ARH) and activated date pits (ADP) were as effective as commercial activated charcoal (CAC) in the reduction of the effluent COD reaching a maximum of 83% using 180 g/L ARH and 76% using 120 g/L ADP. Kinetically, the results showed that reduction of COD onto both ADP and ARH was better fitted to pseudo-second-order model which involved particle/pore diffusion. In addition, equilibrium adsorption data for the reduction of COD effluent ADP and ARH was best represented by the Langmuir model.

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Purification of liquid fuel from nitrogenated compounds is of interest in order to protect the automotive engines and the environment from its harmful effects represented in corrosion, formation of gums in engines, and evolution of NOx gases. In the current report, composites from metal organic framework (MOF) and natural fabric (cotton and wool) was designed and applied in removal of nitrogenated compounds from liquid fuel. MOF based on Al, namely, MIL-53-NH 2 , was immediately formed inside fabric to produce a MIL-53-NH 2 @fabric composite. The contents of MOF onto fabrics were 185.0 mg/g (≈ 22.4 of Al mg/g) for cotton and 234.5 mg/g (≈ 28.4 of Al mg/g) for wool. Infrared and X-ray spectra confirmed the formation of MIL-53-NH 2 MOF within natural fabrics. The microscopic observations for composites showed that the compositions of fabrics played a main role in the morphology of the incorporated MOF. The formed composites were applied in adsorption of indole and quinoline from liquid fuel, and the adsorption was fitted well to the Langmuir isotherm. Maximum adsorption capacities of nitrogenated compounds were significantly enlarged from 87.7 and 125 mg/g onto cotton to 149.3 and 178.6 mg/g onto the composite, respectively. In the case of wool, maximum capacities were increased from 121.5 to 163.9 mg/g and 156.4 to 204.1 mg/g after incorporation of MIL-53-NH 2 MOF into the fabric. The adsorption capacity of the composite was diminished by 19.2%−40.0% by applying four regenerated cycles. It was found that adsorption capacities were linearly functioned with MOF and Al contents onto fabrics. Such a stable composite against recycling could be highly applicable as a filter in fuel purification and could be used many times with substantial adsorption efficiency.

The objective of this study was to investigate the extent of contamination of some of the most used paper denominations of the Egyptian currency (25 PT). Sixty-nine bills in circulation were collected from November 2003 through January 2004. A swab from each bill was cultured on nutrient agar and incubated at 37 degrees C for 48 h. Results showed that over 65% of these bills had a bacterial count above 5.0 cm2. A preliminary identification of organisms present on these paper notes was done using selected Petri dishes with well-defined colonies.

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<p>The adsorption of nickel from liquid solutions onto carbonized date pits (CDP) and rice husks (CRH) has been investigated in the current study. The process was studied in a batch system with respect to the initial pH, contact time, temperature, adsorbent dose and nickel initial concentration. The results showed that the experimental data was well represented by first order model for CDP and second order model for CRH. Based on the kinetic modeling, the apparent activation energies calculated were 7.84 kJ and 18.502 kJ/mol for CDP and CRH, respectively. The results also indicated that process of nickel uptake by CDP and CRH was physical adsorption process. The equilibrium data for CDP indicated that it fitted both Freundlich and Langmuir models. However, adsorption onto CRH fitted Freundlich model better based upon the higher value of R² obtained. The thermodynamic parameters (ΔH°, ΔS° and ΔG°) calculated from the experimental data indicated that the process was endothermic and spontaneous.</p>