Determination of Copper, Iron, Nickel and Zinc in fuel kerosene by FAAS after adsorption and pre-concentration on 2-aminothiazole-modified silica gel

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Square-wave voltammetry applied to the analysis of the dye marker, solvent blue 14, in kerosene and fuel alcohol

The purpose of this paper is to develop an electroanalytical method based on square-wave voltammetry (SWV) for the determination of the solvent blue 14 (SB-14) in fuel samples. The electrochemical reduction of SB-14 at glassy carbon electrode in a mixture of Britton-Robinson buffer with N,N-dimethyiformamide (1:1, v/v) presented a well-defined peak at-0.40 V vs. Ag/AgCl. All parameters of the SWV technique were optimized and the electroanalytical method presented a linear response from 1.0 x 10(-6) to 6.0 x 10(-6) mol L-1 (r = 0.998) with a detection limit of 2.90 x 10(-7) mol L-1. The developed method was successfully utilized in the quantification of the dye SB-14 in kerosene and alcohol samples with average recovery from 93.00 to 98.10%.

Performance and emissions of a gas turbine engine using ox tallow ethyl-ester blended with kerosene

The performance and emissions behavior of a Rover 1S/60 turboshaft engine when operated with several blends of aviation kerosene and ox tallow ethyl-ester are shown in this article. The tests were performed with a compressor shaft coupled to an hydraulic dynamometer where data of power and mass fuel flow were collected to determine the brake specific fuel consumption. A flue gas analyzer was positioned at the exhaust duct to collect oxygen, carbon dioxide, carbon monoxide and nitrous oxides. An increase in the specific fuel consumption was observed due to the lesser lower heating value of the most oxygenated blends. However, reductions of CO, CO2 and NO (x) have been observed and no-significant ill effects have occurred in the turbine operation.

Biosurfactant synthesis by Pseudomonas aeruginosa LBI isolated from a hydrocarbon-contaminated site

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Rhamnolipid emulsifying activity and emulsion stability: pH rules

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Evaluation of Lubricating Oil Preparation Procedures for the Determination of Al, Ba, Mo, Si and V by High-Resolution Continuum Source FAAS

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Voltammetric sensing of the fuel dye marker Solvent Blue 14 by screen-printed electrodes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Different lubricating oil treatments for the determination of Cu, Cr, Fe, Ni, Sb, Pb, and Zn by HR-CS FAAS

Microwave-assisted acid decomposition, direct dilution in kerosene, and oil-in-water emulsion were evaluated as lubricating oil pretreatment procedures for Cu, Cr, Fe, Ni, Pb, Sb, and Zn determination by High-Resolution Continuum Source Flame Atomic Absorption Spectrometry (HR-CS FAAS). For wet digestion, results were compared with those obtained by Flame Atomic Absorption Spectrometry (FAAS). The ultrasound probe used in emulsions sonication contaminated samples with Cr, although better results have been observed for the other six elements in this condition. In general, recovery percentages ranging from 81-106%(Cu), 80-107%(Cr), 85-114%(Fe), 82-116%(Ni), 86-117%(Pb), 85-115%(Sb), and 81-114%(Zn) were obtained. The HR-CS FAAS showed to be faster and more sensitive than FAAS.

Hollow silica particles from microemulsion

Silica particles were obtained by addition of diluted soluble sodium silicate in sodium 1,2 bis (2-ethylhexyloxycarbonyl)-1-ethenesulfonate reverse microemulsions, in which aqueous phase was nitric acid solution and the water/surfactant ratio (W) was 5 or 10. Products, whether washed or not, were dried at 100 degrees C and suspended in different solvents: heptane, water, kerosene or pentane for making SEM measurements. Thermal treatments of washed silica samples were carried out at 900 degrees C and 1200 degrees C. Silica particles of sizes from 1 to 10 mu m were obtained at room temperature without changing their shape due to thermal treatment and crystallization. SEM micrographs show hollow particles suggesting that silica preferably polymerizes on microemulsion droplet interface where ionic strength of nitric acid aqueous solution is favourable for silica polymerization reaction. (C) 1999 Elsevier B.V. B.V. All rights reserved.

Production of Pseudomonas aeruginosa LBI rhamnolipids following growth on Brazilian native oils

Oils from Buriti (Mauritia flexuosa), Cupuacu (Theobroma grandiflora), Passion Fruit (Passiflora alata), Andiroba (Carapa gitianensis), Brazilian Nut (Bertholletia excelsa) and Babassu (Orbignya spp.) were evaluated as carbon sources for rhamnolipid production by Pseudomonas aeruginosa LBI. The highest rhamnolipid concentrations were obtained from Brazilian Nut (9.9 l(-1)) and Passion Fruit (9.2 g l(-1)) oils. Surface tension varied from 29.8 to 31.5 mN m(-1), critical micelle concentration from 55 to 163 mg l(-1) and the emulsifying activity was higher against toluene (93-100%) than against kerosene (70-92%). Preliminary characterization of the surfactant mixtures by mass spectrometry revealed the presence of two major components showing m/z of 649 and 503, which corresponded to the dirhamnolipid (Rha(2)C(10)C(10)) and the monorhamnolipid (RhaC(10)C(10)), respectively. The monorhamnolipid detected as the ion of m/z 503 is predominant in all samples analyzed. (c) 2005 Elsevier Ltd. All rights reserved.

Utilização de biodiesel animal em turbinas a gás

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Biodegradação de derivados do petróleo com a aplicação de biossurfactante produzido por Bacillus subtilis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Flutuação do lençol freático e sua implicação na recuperação de hidrocarbonetos: um estudo de caso

Pós-graduação em Geociências e Meio Ambiente - IGCE

Métodos eletroanalíticos e cromatográficos aplicados na análise de corantes usados como marcadores em combustíveis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Assessing Bacillus subtilis biosurfactant effects on the biodegradation of petroleum products

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)