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1.
International Journal of Environmental Science and Technology. 2009; 6 (4): 619-628
in English | IMEMR | ID: emr-100274

ABSTRACT

The objective of this study was to explore the extent of 2, 4, 6-trinitrotoluene synthetic solution and red water mineralization by comparing conventional direct ozonation and multi-stage ozonation-biological treatment process. The alkaline hydrolysis was used for remediation 2, 4, 6-trinitrotoluene and red water at pH = 10.9. Nevertheless, the hydroxyl radicals would be generated by ozone decomposition with ozone dose of 0.177 g/L. The samples were subjected to chemical oxygen demand and total organic carbon analysis to monitor pollutants removal. The rate of 2, 4, 6-trinitrotoluene and red water pollutants degradation were quantified using high performance liquid chromatography. 2, 4, 6-trinitrotoluene synthetic solution resulted 55.5% chemical oxygen demand removal by 3 h direct ozonation. Following direct ozonation the biological treatment twenty four hours chemical oxygen demand reached 98.9% and 98.7% removal using humic acid and river water 1% [v/v] inoculation singly and respectively. Conventional direct ozonation showed non significant change in total organic carbon degradation. While on using multi-stage ozone-biological treatment process where humic acid and/or river water were used as inoculums singly and respectively, total organic carbon fulfilled 73% and 98.3% removal. The process was one hour direct ozonation and followed by three days multistage ozone-biological treatment. In multi-stage ozone-biological treatment process, ozonation was effective to decompose total organic carbon and to produce biodegradable dissolved organic carbon easily removed by ozone oxidation up to 98.3% in 2, 4, 6-trinitrotoluene synthetic solution. Pollutants removal achieved 99% in authentic red water effluent using river inoculation 1% [v/v] in 5 days. Nuclear Magnetic Resonance and Fourier Transformation Infra Red methods were performed to confirm types of pollutants content in red water


Subject(s)
Water Pollutants, Chemical , Water , Carbon , Water Pollutants , Waste Disposal, Fluid , Chromatography, High Pressure Liquid
2.
International Journal of Environmental Science and Technology. 2009; 6 (3): 369-378
in English | IMEMR | ID: emr-100998

ABSTRACT

Residue of methanolic extract of Egyptian Jatropha curcas contains bioactive substances such as phenolic compounds, which succeeded to be used as natural antioxidants for the protection of oils and their corresponding biodiesel against oxidative deterioration. In the present work, the residue of Jatropha roots were extracted with methanol and resulting residues, were investigated regarding their content of total phenolic compounds by folin-Cioalteau assay. Further, the antioxidant activities of the extracts were characterized by the 2,2-diphenyl-1-picrylhydrazyl radical method and proved remarkable results. Oxidation stability of Jatropha oil, used fried oil and olive oil and their corresponding biodiesel obtained by conventional transesterification were tested using thermal oxidation. Natural antioxidants such as [alpha-trocopherol], synthetic antioxidants as butylated hydroxytoluene and natural Jatropha root extract were used in the present study in comparison to investigate their addition effect on the oxidative stability of oils and their corresponding biodiesel. In the rapied thermal treatment test, results showed that addition of butylated hydroxytoluene 0.25% was able to stabilize Jatropha oil 6 h, but poorly stabiliz biodiesel. Addition of 0.25% alpha-trocopherol to Jatropha oil showed less oxidation stability after 2 h thermal treatment. Crude root extract addition at 0.25% to Jatropha oil showed good stability up to 4 h thermal treatment while addition of root extract at 0.25% to biodiesel showed better stability up to 6 h thermal treatment. Besides addition of 220 ppm crude root extract to biodiesel was enough sufficient to occure oxidative stabilization. Also Jatropha root residue addition at 400 ppm was effective antioxidant for fresh Jatropha oil


Subject(s)
Gasoline , Antioxidants , Jatropha , Esterification , Phenol , Plant Roots , Plant Extracts , Methanol , Biphenyl Compounds , Picrates , Butylated Hydroxytoluene
3.
International Journal of Environmental Science and Technology. 2008; 5 (3): 391-400
in English | IMEMR | ID: emr-100389

ABSTRACT

Trans esterification of three vegetable oils, sunflower oil, linseed oil and mixed oils as; sun flower-soyabean and olein were carried out using methanol, and potasium hydroxide as catalyst. The methyl esters of the corresponding oils were separated from the crude glycerol and characterized by physical-chemical methods to evaluate their thermal properties. This methods are determination of densities, cloud points, pour points, flash points, kinematic viscosities, hydrogen/carbon ratios, sulfur contents, ash contents and triglycerides. The physico-chem ical characteristic of biodiesel treated with ozone showed improvement of pour point and flash point indicating higher degree of safety for fuel. Methyl esters mixed with their corresponding ozonated oil were subjected to comparison and evaluation for their thermal properties by the thermo gravimetric analysis differential thermal analysis from which the calculated heat of enthalpy and comparison with the heat of conventional diesel. The results showed that the oxygen content of biodiesel samples treated with ozone increased weight% and resulted in more extensive chemical reaction, promoted combustion characteristics and less carbon residue was produced. Gas chromatography appeared more suitable to address the problem of determining/verifying biodiesel methyl ester and showed that methyl ester content was impurity free. Ultra violet-detection was used for rapid quantization of triglycerols. From the analyses performed biodiesel treated with ozone modified the thermal and oxidative stability shown by the high combustion efficiency indicated by the high heat of enthalpy and reducing the emission of particulate matter


Subject(s)
Differential Thermal Analysis , Plant Oils/chemistry , Oxidation-Reduction , Esterification , Plant Oils/isolation & purification , Fatty Acids/analysis , Thermogravimetry
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