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The present study aims to evaluate the growth potential of the P. aeruginosa ATCC9027 strain with molasses as the sole carbon source to produce rhamnolipids. The influence of the cultivation time and substrate concentration on biosurfactant production was investigated by using a complete 3-level factorial design, with the rhamnolipid concentration as the variable response. The strain was able to produce the biosurfactant in all design conditions tested, producing 758.04 mg/L rhamnolipids with 7% v/v substrate concentration in a cultivation time of 120 h. The substrate concentration used in the cultivation step directly influenced the biosurfactant production, and, even with the decrease in biomass growth, the biosurfactant production continued to increase. High Performance Liquid Chromatography (HPLC) revealed the presence of 62.3% mono- (RL1) and 37.6% di-rhamnolipids (RL3). The stability tests showed that the biosurfactant has good performance in extreme conditions of temperature, pH and saline concentration. The emulsification index was also evaluated for several oils and hydrocarbons, obtaining emulsification rates of up to 84.9% for the burnt motor oil. In addition, rhamnolipid showed a good ability to remove spilled oil from the sand, removing 58.51% of burnt motor oil and 70.09% of post-frying soybean oil. The results indicate that molasses, an agro-industrial residue abundant in Brazil, can be used as the only carbon source for quality rhamnolipid production when under optimized conditions, therefore presenting itself as a management option for this residue and, at the same time, providing the production product with high added value. [ABSTRACT FROM AUTHOR]

Composed of hydrocarbons and other substances, petroleum is classified as a nonrenewable source of energy. In its unrefined form, it is called crude oil. Currently, its derivates are widely used in domestic and industrial environments, with the greatest exponent being motor fuels and lubricating oils. Due to the overwhelming demand, new oil wells in the presalt region of Brazil are going to be drilled, which will, in its turn, increase the demand for analysis and require the use of less costly technologies. The purpose of this paper is to present an experimental method that aims at characterizing crude oil samples through their X‐ray scattering profiles without the need for any chemical preparation to be performed in advance, which will enable this method to be used for analyzing samples immediately after their extraction. For the experiment, a portable X‐ray scattering system composed by an X‐ray tube (silver anode) and a Si‐PIN detector was used in order to analyze samples from different wells. The process consisted in establishing a linear relationship between the effective atomic number and the ratio between peak intensities of Compton and Rayleigh scattering from known samples. The linear function, verified experimentally, was then applied to samples of crude oil, and the results showed that it is possible to characterize them on the basis of the Rayleigh to Compton scattering ratio. After the analysis, a multiple comparison test performed on the samples proved that this methodology indeed allows to differentiate samples of different origins and to verify the compatibility of samples extracted from the same well. [ABSTRACT FROM AUTHOR]

The National Solid Waste Policy (PNRS) established by Law 12,305/2010, mentions Reverse Logistics (RL) as a development tool for the return of the production cycle, and also presents instruments for shared responsibility for the life cycle of products. The RL of lubricating oils in post-consumption and return is linked to concern for the environment and sustainability in the business sphere. The aim of this study was to describe the RL process of gas stations and their tax benefits, through bibliographic and documentary research, in addition to an unstructured interview with professionals involved in the process and through a case study. It was found that compliance with environmental obligations imposed by the Government, such as the destination of used or contaminated lubricating oil packaging (OLUC), can be considered inputs that may generate PIS and COFINS credits, and the revenues obtained from the sale of the destination of OLUC may be considered as environmental revenues, as well as the structure of real estate to be measured as environmental assets. [ABSTRACT FROM AUTHOR]

• Portable NIR spectrometer was used to discriminate crude oils from used motor oils. • PLS-DA model discriminated crude oils with precision over 94%. • Naphtha was quantified in gasoline with LOD of 4.4 wt%. • Diesel was quantified in kerosene with LOD of 9.3 wt%. Improper mixtures of: motor oil with crude oil; and derivatives mixed with other derivatives of lesser commercial value were identified in Brazil by companies in the energy sector. This study shows the great response that a portable NIR spectrometer had to discriminate crude oils and derivatives and to quantify them in blends (crude oils with used motor oil; and naphtha, gasoline, diesel, and kerosene). NIR spectra set were acquired in triplicate using a microNIR™ portable spectrometer, where it was possible to discriminate crude oil from used motor oil with 100% sensitivity, specificity, and precision. Regression models can quantify the oil content of a ternary mixture containing two crude oils (light and heavy oil) and a used motor oil with root mean square error of prediction (RMSEP) of 6.2 and 4.8 wt%, and R2p = 0.9871 and 0.9870 for support vector regression (SVR) and partial least squares (PLS), respectively. About the NIR spectra of naphtha, gasoline, diesel, and kerosene, partial least squares discriminant analysis (PLS-DA) allows the identification of any of these products with sensitivity, specificity, and precision of 100%. For the blends of gasoline and naphtha, the limit of detection (LOD), limit of quantification (LOQ), and RMSEP were 1.3, 4.4, and 1.4 wt%, respectively. Likewise, for diesel and kerosene blends, the PLS model allows the identification of the diesel with LOD, LOQ, and RMSEP of 2.8 wt%, 9.3 wt%, and 11.4 wt%, respectively. [ABSTRACT FROM AUTHOR]

• Synthesis and evaluation of new potential biolubricants from castor oil fatty acids. • The less polar samples (BIOBUT) showed better pour point (−48 °C). • BIOWAT samples showed a higher viscosity values (>470 mm2/s at 40 °C). • Thermogravimetric analyses indicated that BIOWAT shows better thermal stability. • Synthesized samples have interesting properties for application as biolubricants. Plants oils have been increasingly gaining acceptance in world markets, due to their great potential as raw material to replace conventional mineral oils for formulation of lubricants. In this study, samples of new potential bio-based lubricant molecules were synthesized from castor oil fatty acids. The synthesis occurred in three steps: esterification with 2-ethyl-1-hexanol, epoxidation and opening of oxirane rings with different nucleophilic agents: 1-butanol (BIOBUT) and water (BIOWAT). The main objective was to study the influence of hydroxyl groups and branching level on physicochemical properties and thermal degradation of samples. The products obtained in each step were characterized by 1H NMR and their physicochemical properties. The results indicated that the less polar samples (BIOBUT) exhibited a better low-temperature performance (PP −48 °C). Furthermore, BIOBUT has superior oxidation stability (IP 4.22 h) compared to BIOWAT (IP 3.27 h). However, the BIOWAT showed a higher viscosity values (> 470 mm2/s at 40 °C). Thermogravimetric analyses have indicated that BIOWAT shows better thermal stability. Finally, the activation energy determined for the first thermal event for BIOWAT (151 kJ.mol−1) was higher than BIOBUT. [ABSTRACT FROM AUTHOR]