(Pdf) bromine number prediction for colombian naphthas using near-infrared spectroscopy and chemometric methods electricity cost calculator

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Near-infrared (NIR) spectroscopy has been successfully applied to the determination of API (American Petroleum Institute) gravity of atmospheric residue (AR), which is the heaviest fraction in crude oil. This fraction is completely dark and very viscous. Preliminary studies involving Raman and infrared (IR) spectroscopies were also evaluated along with NIR spectroscopy. The Raman spectrum of AR was completely dominated by stronguorescence from electricity trading strategies poly- cyclic aromatic hydrocarbons, called asphaltenes. IR spectroscopy provided reasonable spectral features; however, its spectral repro- ducibility was poorer and noisier than that of NIR. Although ab- sorption bands in the NIR region were broad and less characterized, NIR provided better spectral reproducibility with higher signal-to- noise ratio (which is one of the most important parameters in quan- titative calibration in comparison to Raman and IR spectroscopies). Partial least-squares (PLS) regression was utilized to develop cali- bration models. NIR spectra of AR samples were broad, and base- lines were varying due to the strong absorption in the visible range. However, the necessary information was successfully extracted and correlated to the reference API gravity with the use of PLS regres- sion. API gravities in the prediction set gas x reviews ratings were accurately predicted with an SEP (standard error of prediction) of 0.22. Additionally NIR showed approximately three times better repeatability com- pared to the ASTM reference method, which directly inuences the process control gas and sand performance. Index Headings: Near-infrared; Infrared; Raman; Heavy petroleum products; API gravity; Partial least-squares.

In this research, an original way to obtain models able to predict the asphaltene content in vacuum residua by mid-infrared attenuated total reflectance (MIR-ATR) spectroscopy by reduction of X variables was developed. Partial least-squares regression (PLS-R) was used to reach this goal. A total of 69 samples for calibration and 18 samples for external prediction were used. It was demonstrated that dimensional reduction of the dependent variables greatly improves the prediction power of models. This methodology was evaluated in three processes of modeling, and 18 predictive models are reported. The model with better predictability was constructed with 35 spectral intensities, in which errors of calibration, validation, and prediction were 1.354, 2.095, and 1.24, respectively, and in which regression coefficients of calibration, validation, and prediction were 0.9799, 0.9720, and 0.9838, respectively. The electricity usage in the us spectral intensities in the best model are part of nine clearly differentiated functionalities. On the basis of this, it was possible to infer structural characteristics of the asphaltenes that are part of the studied vacuum residua; it means that structure–functionality correlations were reached.

Electric conductivity of materials is defined by a competition of several mechanisms of charge carrier movement: phoretic, ionic and electron-hole jumping. The relative contribution of them is not constant when thermodynamic conditions are changing. Paraffine and naphtene hydrocarbons are typical dielectrics. Formation of supermolecular structures is accompanied by ordering of asphaltene-resin and polyaromatic molecules. Solvate shells contain the molecules with less molecular masses. The disperse particle from the centre to periphery is characterized by reduction of conductivity from the values peculiar to good semiconductors in a nucleus, average in intermediate phase to typical for dielectrics in the disperse media. Threshold of the mobility of charge carriers is determined by temperature gas vs electric stove safety, pressure, strength of the external field, width of the forbidden zone, and nature of components of the disperse media and phase. Spectra of conductivity of model asphaltene solutions and Kumkols-kaya oil in frequency range from 10(-3) up to 10(6) Hz are measured for pressures up to 1 GPa in temperature interval from 250 to 320 K. Particularly at the analysis of spectra of conductivity the technique offered by Sheu and Mullins is used. Dependences were approximated by power-law functions according to the concept of Jonscher’s the universal response gas finder near me. Influence of pressure and temperature to the exponents is analyzed. Values of activation energy are determined. Received data can be useful for prognosis of oil phase behavior at high pressures.

Asphaltenes, the most aromatic of the heaviest components of crude oil, are critical to all aspects of petroleum use, including production, transportation, refining, upgrading, and heavy-end use in paving and coating materials. As such, efficiency in these diverse disciplines mandates proper chemical accounting of structure−function relations of crude oils and asphaltenes, the vision of petroleomics ( Asphaltenes, Heavy 3 main gas laws Oils and Petroleomics; Mullins, O. C., Sheu, E. Y., Hammami, A., Marshall, A. G., Eds.; Springer: New York, 2007). Indeed, the molecular characterization of asphaltenes is required as well as the detailed understanding of the hierarchical colloidal structures of asphaltenes and petroleum. With great prescience, Professor Teh Fu Yen and co-workers proposed a hierarchical model of asphaltenes to account for many of their characteristics known at that time (Dickie, J. P.; Yen, T. F.Macrostrucutres of asphaltic fractions by various instrumental methods. Anal gas dryer vs electric dryer calculator. Chem. 1967, 39, 1847−1852). This model is rightfully known as the Yen model. Nevertheless, at the time the Yen model was formulated, there were many order-of-magnitude uncertainties in asphaltene science that precluded establishing structure−function relations and causality, thereby rendering the Yen model somewhat phenomenological. Petroleum science has advanced greatly in recent years enabling development of a much more specific model yet still based on precepts of the Yen model; we call this the “modified Yen model”. The modified Yen model is shown to account for wide ranging, myriad properties of asphaltenes, including their dynamics. In addition, the modified Yen model gas laws worksheet chapter 5 answers has even proven successful for understanding interfacial phenomena involving asphaltenes. Moreover, the modified Yen model accounts for fundamental observations in oil reservoirs and is now propelling significantly improved efficiency in oil production. The modified Yen model is a simple, yet powerful construct that provides the foundation to test future developments in asphaltene and petroleum science; refinement of the modified Yen model is an expected outcome of this process.

In this work eight chemometrics models to predict saturates, aromatics, resins and asphaltenes (SARA) composition of fifty Colombian crudes oils using Fourier transform infrared coupled to attenuated total reflectance (ATR–FTIR) spectra were developed. The 4 gas planets samples were correlated by similarity using principal components analysis (PCA) with their ATR–FTIR spectra. The validation showed … [Show full abstract] satisfactory results for the prediction of the SARA analysis of crude oils. For each SARA component, standard errors of prediction (SEP) for light samples were 1.9, 1.7, 1.3, and 0.4. For heavy samples SEP were 2.5, 1.7, 3.7, and 1.4. In all cases, the coefficients of correlation (R2) between the values of reference and those predicted by the models were superior to 0.95. The IR spectroscopy coupled with the ATR cell plus chemometric techniques provide an alternative way for the quantitative prediction of the wt% SARA group-types with minimal handling of the samples in a short period of time. Read gas prices going up 2016 more

In this research, an original way to obtain models able to predict the asphaltene content in vacuum residua by mid-infrared attenuated total reflectance (MIR-ATR) spectroscopy by reduction of X variables was developed. Partial least-squares regression (PLS-R) was used to reach this goal. A total of 69 samples for calibration and 18 samples for external prediction were used. It was demonstrated … [Show full abstract] that dimensional reduction of the dependent variables greatly improves the prediction power of models. This methodology was evaluated in three processes of modeling, and 18 predictive models are reported. The model with better predictability was constructed with 35 spectral intensities, in which errors of calibration, validation, and prediction were 1.354, 2.095, and 1.24, respectively, and in which regression coefficients of calibration, validation, and prediction were 0.9799, 0.9720, and 0.9838, respectively. The spectral intensities in the best model are part of nine clearly differentiated functionalities. On the basis of this, it was possible to infer structural characteristics of the asphaltenes that are part of the studied vacuum residua; it means that structure–functionality g gas lol correlations were reached. Read more