scholarly journals Prediction of the Flash Point of Binary and Ternary Straight-Chain Alkane Mixtures

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
X. Li ◽  
P. P. Duan ◽  
K. N. Sun ◽  
X. Yan

The flash point is an important physical property used to estimate the fire hazard of a flammable liquid. To avoid the occurrence of fire or explosion, many models are used to predict the flash point; however, these models are complex, and the calculation process is cumbersome. For pure flammable substances, the research for predicting the flash point is systematic and comprehensive. For multicomponent mixtures, especially a hydrocarbon mixture, the current research is insufficient to predict the flash point. In this study, a model was developed to predict the flash point of straight-chain alkane mixtures using a simple calculation process. The pressure, activity coefficient, and other associated physicochemical parameters are not required for the calculation in the proposed model. A series of flash points of binary and ternary mixtures of straight-chain alkanes were determined. The results of the model present consistent experimental results with an average absolute deviation for the binary mixtures of 0.7% or lower and an average absolute deviation for the ternary mixtures of 1.03% or lower.

2000 ◽  
Vol 78 (2) ◽  
pp. 184-190 ◽  
Author(s):  
Karina M De Fina ◽  
Tina L Sharp ◽  
Michael A Spurgin ◽  
Ivette Chuca ◽  
William E Acree, Jr. ◽  
...  

Experimental solubilities are reported at 25.0°C for diuron (also called 3-(3,4-dichlorophenyl)-1,1-dimethyl urea) dissolved in 49 different organic nonelectrolyte solvents containing ether-, chloro-, hydroxy-, ester-, methyl-, and tert-butyl-functional groups. Results of these measurements are used to test the applications and limitations of expressions derived from Mobile Order theory. For the 28 nonalcoholic solvents for which predictions could be made computations show that Mobile Order theory does provide fairly reasonable estimates of the saturation mole fraction solubilities. Average absolute deviation between predicted and observed values is 60.1%. Diuron solubilities in the alcohol solvents are used to calculate stability constants for presumed solute-solvent hydrogen bonds that are believed to occur in solution.Key words: pesticide, diuron solubilities, organic nonelectrolyte solvents, solubility predictions.


OENO One ◽  
2017 ◽  
Vol 51 (4) ◽  
pp. 401-407 ◽  
Author(s):  
Daniel Molitor ◽  
Lucien Hoffmann ◽  
Marco Beyer

Aims: The present analyses aimed at evaluating the performance of two models for estimating the overall effect of combining two or more measures (leaf removal, cluster division, late shoot topping, botryticide application, bioregulator application) for controlling grape bunch rot based on the efficacy of the individual measures.Methods and results: Field trials with the white Vitis vinifera cultivars Pinot gris and Riesling on the efficacy of three bunch rot control measures applied either alone or in combination were analyzed. Bunch rot disease severities prior to harvest were assessed and efficacies were calculated for each treatment. Observed efficacies of single measures were used to estimate the overall efficacies of all possible measure combinations. Calculated efficacies matched observed efficacies more accurately when assuming multiplicative interaction among the individual measures (R2 = 0.8574, p < 0.0001; average absolute deviation: 7.9%) than in case of assuming additive effects (R2 = 0.8280; average absolute deviation: 14.7%).Conclusions: The multiplicative approach assumes that each additional measure is affecting (in case of efficient measures: reducing) the disease severity level as the result of the additional treatments rather than compared to the disease severity level in the untreated control.Significance and impact of the study: The high goodness of fit as well as the observed low deviations between the estimated and the observed efficacies suggest that the multiplicative approach is appropriate for estimating the efficacy of combined viticultural measures in a complex practical bunch rot control strategy assembled of different modules.


2020 ◽  
Vol 66 (4 Jul-Aug) ◽  
pp. 504
Author(s):  
L. F. Ramirez-Verduzco

Aqueous alkanolamines solutions are widely used in petroleum refineries to remove acid gases from hydrotreated streams. The knowledge of physical properties in this kind of solutions is useful for the correct design, operation, and control of sweetening processes. Due to the above, we carried out a study on the density of the ternary mixture: 2-Amino-2-Methyl-1-Propanol (AMP) + Diethanolamine (DEA) + Water (H2O). Density was measured by means of the vibrating tube method with an uncertainty of 2×10-4 g·cm-3.  The experimental data was obtained in the entire concentration range, temperatures from 303.15 to 333.15 K, and pressure of 101.3 kPa. In addition, the following three prediction methods were tested to estimate the density of the blend: mixing rule, polynomial correlation, and excess molar volume. The best prediction was obtained by means of the excess molar volume through the Redlich-Kister and Cibulka equations, where an average absolute deviation (AAD) of 0.02%, correlation coefficient (R) of 0.9999, and standard deviation (<s>) of 3×10-4 g·cm-3 were obtained.


Author(s):  
K. Shevchenko ◽  
A. Grigorov ◽  
I. Sinkevich

In order to improve the performance properties, in particular viscosity-temperature, of boiler fuel, it is proposed to combine them with narrow fuel fractions obtained by thermal destruction of secondary polymer raw materials (low pressure polyethylene and polypropylene). When compounding grade 100 fuel oil with narrow fuel fractions, the values ​​of density are reduced to 865 (873) kg / m3, conditional viscosity to 2.50 (2.63) deg. um., pour point up to 8 (13) °C), sulfur content up to 0.17 wt%. and the lower heat of combustion increases to 43606 (43850) kJ / kg. At the same time, there is a gradual decrease in the value of the flash point to 114 (127) °C. This reduction is a negative point, which leads to increased fire safety of fuel oil during its use, storage, pumping and transport. However, the values of the flash point, according to the requirements of regulatory documentation, are within acceptable limits. That is, the value of this indicator can limit the content of fuel oil in narrow fuel fractions. It is determined that the rational concentration of narrow fuel fractions in the composition of fuel oil grade 100, is within 30% of the mass. Within these limits, there is a permissible decrease in flash point values – an indicator that characterizes the fire hazard of fuel oil during its use, storage, pumping and transportation against the background of improving other performance properties of fuel oil. The production of the proposed compound boiler fuel on the one hand allows to expand the raw material base of the process by involving in the production process secondary polymer raw materials – solid waste subject to mandatory disposal, on the other – to meet existing demand for boiler fuel by increasing its production.


Author(s):  
Jonny Nordström ◽  
Hendrik J. Harms ◽  
Tanja Kero ◽  
Maryam Ebrahimi ◽  
Jens Sörensen ◽  
...  

Abstract Background Quantification of myocardial blood flow (MBF) with PET requires accurate attenuation correction, which is performed using a separate CT. Misalignment between PET and CT scans has been reported to be a common problem. The purpose of the present study was to assess the effect of PET CT misalignment on the quantitative accuracy of cardiac 15O-water PET. Methods Ten clinical patients referred for evaluation of ischemia and assessment of MBF with 15O-water were included in the study. Eleven different misalignments between PET and CT were induced in 6 different directions with 10 and 20 mm amplitudes: caudal (+Z), cranial (− Z), lateral (±X), anterior (+Y), and anterior combined with cranial (+ Y and − Z). Blood flow was quantified from rates of washout (MBF) and uptake (transmural MBF, MBFt) for the whole left ventricle and the three coronary territories. The results from all misalignments were compared to the original scan without misalignment. Results MBF was only minorly affected by misalignments, but larger effects were seen in MBFt. On the global level, average absolute deviation across all misalignments for MBF was 1.7% ± 1.4% and for MBFt 5.4% ± 3.2 Largest deviation for MBF was − 4.8% ± 5.8% (LCX, X + 20) and for MBFt − 19.3% ± 9.6% (LCX, X + 20). In general, larger effects were seen in LAD and LCX compared to in RCA. Conclusion The quantitative accuracy of MBF from 15O-water PET, based on the washout of the tracer, is only to a minor extent affected by misalignment between PET and CT.


Author(s):  
Sepehr Sadighi ◽  
Arshad Ahmad ◽  
Akbar Irandoukht

Hydrocracking is an important upgrading process in the petroleum refinery, and it is generally used to process feedstocks ranging from vacuum gas oil (VGO) to vacuum residue. In this work, hydrocracking of VGO using a dual functional amorphous catalyst was carried out at a pilot scale unit under the following reaction conditions: liquid hourly space velocity (LHSV) from 1 to 1.5 hr-1 and reaction temperatures of 360-440°C at the constant pressure and hydrogen to oil, 156 bar and 1780 Nm3/m3, respectively. The effluent of the reactor was characterized to dry gas, naphtha, kerosene, diesel and unconverted VGO or residue. The pilot tests demonstrated that performing experiments beyond the temperature, recommended by catalyst vendor, lead the process to unstable hydrocracking. To describe the yield of hydrocracking products a five-lump discrete lumping approach with ten reactions was proposed. At first, the kinetic model contained twenty kinetic constants which were estimated by using the conventional objective function. The estimated parameters showed that the tendency of the catalyst to convert VGO to gas and naphtha was negligible whilst rate constants for hydrocracking of VGO to middle distillates were considerably high which was compatible with the nature of amorphous hydrocracking catalysts. After evaluating the magnitude of reaction rates and eliminating the ignorable constants, the network was reduced to six reactions in which only nine parameters were needed. The predictions indicated that the latter network could fit the yield of products more acceptable as if the average absolute deviation between experimental and calculated yields was descended from 16.25% to 12.6%. Then, to have a better prediction, a weighted objective function was used in which weight factors were calculated by a proposed weighted least square expression. The results confirmed that this approach could reduce average absolute deviation of model to 10.75%, and it created a fairly even distribution of deviation between hydrocracking products.


Processes ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 912
Author(s):  
Kaiyue Wang ◽  
Xiaoyan Sun ◽  
Shuguang Xiang ◽  
Yushi Chen

The aniline point (AP) is an important physical property of a petroleum fraction. The AP gives an indication of the aromatic hydrocarbon content in a hydrocarbon mixture and can also be an indicator of the ignition point of a diesel fraction. In this study, common estimation methods were introduced and evaluated, and their limitations were analyzed. Multiple linear regression was used in constructing a quantitative function to solve for the AP using the average boiling point and specific gravity. The iterative modification algorithm of the ternary interaction algorithm was used to obtain the predicted value of the petroleum fraction AP, and the proposed algorithm was tested using 127 actual petroleum fractions. The average estimation deviation of the proposed method was 3.55%; hence, compared to the commonly used estimation methods, the prediction accuracy was significantly improved. This method offers important practical value in the calculation of the petroleum fraction AP and other petroleum fraction properties, thereby providing reference significance.


2020 ◽  
Vol 44 (12) ◽  
pp. 4858-4868 ◽  
Author(s):  
Alla P. Toropova ◽  
Andrey A. Toropov ◽  
Danuta Leszczynska ◽  
Jerzy Leszczynski

Reliable information related to the flash point of ternary mixtures assists in the rational classification of different ternary mixtures of liquids.


2020 ◽  
Vol 840 ◽  
pp. 501-506
Author(s):  
Ardika Nurmawati ◽  
Rizky Tetrisyanda ◽  
Gede Wibawa

The addition of alcohol as an oxygenated compound in gasoline blends may increase the vapor pressure of gasoline mixture. As a result, the study of vapor-liquid equilibrium for gasoline component and alcohol is necessary. In this study, the vapor-liquid equilibrium of isobutanol – isooctane/n-heptane blends were obtained experimentally at temperatures in the range 303.15 to 323.15 K using modified simple quasi-static ebulliometer. The apparatus was validated by comparing the vapor pressure of pure isobutanol, isooctane, and n-heptane with the published data and giving average absolute deviation (AAD) between experimental and calculated ones with magnitude less than 1.0%. The addition of isobutanol with the mole fraction range from 0.2 to 0.6 would increase the vapor pressure of the isooctane and n-heptane up to 12% and 14% respectively. The vapor pressure of binary mixtures was correlated with the Wilson, Non-random two-liquid (NRTL), and Universal quasi-chemical (UNIQUAC) equations with AAD 1.6%, 1.5%, and 1.7%, respectively for isobutanol + isooctane system and 1.8%, 1.7%, and 2.0%, respectively for isobutanol + n-heptane system. The systems studied show positive deviation from Raoult’s Law.


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