Assessing Bacillus subtilis biosurfactant effects on the biodegradation of petroleum products

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Petroleum products biodegradation profile similarity evaluated by F test comparison of weekly CO2 production

Strategies applied to bioremediation contaminated environments are necessary to identify limitations towards biodegradation and to predict remediation performance and thereby rule out technologies that may be inappropriate for the clean-up of the substances of concern. Respirometry applied to bioremediation offers a series of advantages for obtaining CO2 production data when compared to other procedures. It was possible to determinate information regarding the atmosphere's CO2 concentration inside a respirometer containing petroleum products. Afterwards, the CO2 data obtained underwent an in depth statistical analysis by F test. There are some noticeable biodegradation similarity among some substances, such as weathered motor oil and gasoline. Such data provides reliability when revealing important information about how the biodegradation processes happens in those residual oils.

Determination of water insoluble dyes used as marking of commercial petroleum products using high-performance liquid chromatography with electrochemical detection

This paper describes an analytical method using high-performance liquid chromatographic (HPLC) separationcoupled with electrochemical detection to detect three dyes, Solvent Blue 14 (SB-14), Solvent Blue 35 (SB-35) andSolvent Red 24 (SR-24). The dyes were eluted and separated using a reversed-phase column (C-8) under isocraticelution with the mobile phase containing a mixture of acetonitrile/ammonium acetate (5.0 mmol L1) at the ratio of75: 25 (v/v). Two sample pretreatment methods were tested and successfully applied to quantify SB14, SB-35 and SR-24 dyes in gasoline samples. The proposed method was simple, fast and suitable to detect and quantify marker dyes ingasoline sample at low concentration.