THE APPLICATION OF CHEMISTRY IN ENVIRONMENT
Year:2013 | Volume:4 | Issue:16|Papers Count:8

In the present work a Skin Shrimp used for removal of radioactive pollution (Uranium and Thorium) from contaminated solutions. The effect of various parameters such as pH, contact time, metal concentration and amount of adsorbent on the process was investigated. The adsorption efficiencies were found to be pH dependent, maximum removal of uranium and thorium ions was obtained at pH=5. The equilibrium time was attained after 10 min. The results showed that the best conditions for the removal of 100 ppm Urani urn and Thorium ions with the yield of 99%and 80% respectively, was achieved by using 3 g of sorbent at pH 5. Investigations of kinetics of the process were performed considering pseudo second-order model. This model predicted chemiosorption as the adsorption mechanism of the process. Langmuir, Freundlich and Temkin models were tested for describing the equilibrium data. It was found that Langmuir model for Uranium and Freundlich model for Thorium describes well the experimental data.

The Hack reactions are useful and effective reactions in the synthesis of organic compounds. This reaction completed by pd catalyst for c-c band creation. Use of pd catalyst in homogenous reaction systems are limited, which is came's from its difficulties in separation of pd and legend from final products and recovery. For this, many solid materials such as silica, cellulose, chitosan was expanded. In these years, science and technology more enforce on the compatibility by environment. Biopolymer is a good choice for discovery of stabilized catalyst. In this study, we prepared an unhomogenous palladium that successfully used as good catalyst for Hack reaction.

Degradation of Ceftriaxone antibiotic in aqueous solution by TiO2 photocatalysis under UVA irradiation was studied The amount of TiO2 has an important influence on the reaction rate. The results showed that pH had a great effect on antibiotic degradation. The optimum conditions for the photocatalytic degradation of Ceftriaxone were found to be pH= 5 and catalyst dosage of 0.06 gL-1. The semi-logarithmic graphs of the concentration of Ceftriaxone in the presence of different concentrations of TiO2 versus irradiation time yield straight lines indicating pseudo-first order reaction and UV/TiO2 photocatalysis is effective for degradation Ceftriaxone in aqueous solution.

In this result photocatalytic degradn of 4-chatioloro-2-nitro phenol with use of oxide catalyst (ZnO) were studied. According the findings of this research, for detemining of optimum conditions of the catalyst, the effect of concentration of 4-chloro-2-nitro phenol by UV-Vis were examined. Finding revaled that the most degradation was achieved at 60 minutes. Results showed that the degradation was influenced catalyst concentration and the varation in concentration of 4-chloro-2-nitro phenol don't effect on degree of degradation.

In this research the effects of two factors such as species and nutrient solutions (Hoagland 100)%, Hoagland 50%, MS 5%, MS 10% and MS 15% were studied ill the species of mint (Mentha spicata, Mentha longifolia and Mentha piperita). The results analysis of variance showed that the effect of species and the nutrient content of peppermint oil is significant at the one percent level. The interaction between the species and nutrient essential oil was. significant at the 5% level. The essential oil of species was 0.82-2.4 %Comparison of the results showed that mint species are significant differences in the amount of essential oil.The highest essential oils (2.4)% is in the M.piperita and Hoagland solution (100) % and the lowest essential oils (0.82). % is in the M.longifolia and MS (5)% Most of the essential oil is in M. spicata and Hoagland solution (l00). %This study shows that different species of mint respond better than MS compared with Hoagland nutrient solution. Menthol is the most important essential oil of pepperrnint in the Hoagland solution (100), % Alpha-Terpinyl Acetate is the most important essential oil of Mentha spicata in the MS nutrient solution (15) % and Carvene is the most important essential oil of Mentha longifolia in the MS nutrient % were observed solution (10).

Schiff bases of substituted salicylaldehydes have been synthesized and characterized by IR, NMR and elemental analysis. All synthesized compounds were screened for their antimicrobial activity against some clinically important bacteria: Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), Enterococcus feacalis (ATCC 29212) by Agar ditch method using N,N- dimethylformamide (DMF) and l,4-dioxane as solvents. Activity data shows a higher activity of the compounds in DMF with the bromo substituted imines more potent than the nitro substituted compounds.

Furnace in petrochemical and refinery processes are major energy consumers. Use of variety form of energy, particularly fossil fuels is the main cause of air pollution and climate change. The Combustion is the first generation source energy that the human achieved. Today, more than 95% of the world energy supplied from Combustion, but most combustion processes is harmful effects on the environment, Hence, it is necessary that theses undesirable processes attained to lowest. Various factors effect on the combustion process, such as this factor is fuel injection angle. In this study we focuses on the effect of the fuel injection angle from Brenner type by using Computational Fluid Dynamics and our target found the best geometry of the Brenner type to reduce pollutions.

One of the main problems faced by different communities in the present is environmental problems. The main cause of problem is pollutants that often produced by industrial activities. Major industries especially oil and petrochemical industries have played a major role in the production of these pollutants so that the combustion of fossil fuels is the main source of air pollution. But the fuel that burned in a furnace is contained impurities and this work result to create of other components in the combustion products that are pollutants from combustion. In the present study, with using of Computational Fluid Dynamics was investigated to affect the fuel injection angle to reduce pollutant of carbon monoxide.