Engenharia Química
URI permanente desta comunidadehttps://repositorio.fei.edu.br/handle/FEI/25
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10 resultados
Resultados da Pesquisa
- Experimental study and correlation of the excess molar volume of binary liquid solutions of (amines + water) at different temperatures and atmospheric pressure(2022-03-05) MUNOZ, P. A. R.; OLIVIERI, G. V.; Ronaldo Santos; Ricardo Torres© 2021, Associação Brasileira de Engenharia Química.Experimental data of density have been measured for binary liquid mixtures containing {amines (n-butylamine, or s-butylamine, or t-butylamine, or diethylamine, or propylamine) + water}, over the entire range of composition at temperatures between 283.15 and 303.15 K, and atmospheric pressure. The density values enabled the determination of the thermal expansion coefficients. The excess molar volume, VmE, was calculated using the experimental data, from which a Redlich–Kister type polynomial was fit, enabling the determination of the partial molar volumes, the excess partial molar volumes, the apparent molar volumes and the excess partial molar volumes at infinite dilution. The VmE values were also used to test the applicability of the Extended Real Associated Solution Model (ERAS Model). The results for the studied systems suggest that structural effects and chemical interactions must predominate over other possible effects. The magnitude of VmE for the studies systems led to the following order: n-butylamine > propylamine > s-butylamine > diethylamine > t-butylamine.
- Volumetric properties of binary mixtures of glycerol + alkanols (C1-C4): Experimental study and application of the Peng–Robinson–Stryjek–Vera equation of state(2022-05-05) VICENTE, V. B.; OLIVIERI, G. V.; Ronaldo Santos; Ricardo TorresVolumetric properties for binary mixtures of (glycerol + methanol, or + ethanol, or + 1-propanol, or + 2-propanol, or + 1-butanol) have been determined as a function of composition using experimental data of density at T = (288.15, 293.15, 298.15, 303.15 and 308.15) K and p = 92.3 kPa. The density measurements have been determined by using a vibrating-tube densimeter. The density values enabled the determination of the thermal expansion coefficient and the excess molar volume. The values of excess molar volume were correlated by a Redlich-Kister polynomial and by the Peng-Robinson-Stryjek-Vera equation of state (PRSV EOS). These values were also used in the estimation of the partial molar volumes, excess partial molar volumes and apparent molar volumes. Three different methods were used to determine the partial molar volumes at infinite dilution. For all studied systems, the values of excess molar volumes were negative over the entire composition range and suggest predominance of chemical and structural effects.
- Effects of rhamnolipid bio-surfactant and sodium dodecylbenzene sulfonate (SDBS) surfactant on enhanced oil recovery from carbonate reservoirs(2022-01-03) IMANIVARNOSFADERANI, M. R.; GOMARI, S. R.; Ronaldo Santos© 2022, Associação Brasileira de Engenharia Química.Bio-surfactant solutions have been point out as a promissory component to replace fossil-derived surfactants to improving the displacement efficiency in enhanced oil recovery (EOR) methods. This study compares the performance of rhamnolipid as a bio-surfactant and sodium dodecylbenzene sulfonate (SDBS) as a synthetic surfactant in EOR from carbonate reservoirs. The effects of their use were evaluated by considering the effect of different levels of salinity and the results of various well-established experimental tests such as of fluid-phase behaviour, wettability alteration, interfacial tension (IFT) reduction, and core flooding. The rhamnolipid bio-surfactant has been recognized as a better surface agent used to change the wettability of calcite to a strong water-wet system in comparison to sodium dodecylbenzene sulfonate. The results confirmed that when the salinity of low-saline brine was increased to 0.6 M, with a concentration of 0.5 wt. % of rhamnolipid, the wettability of the rock surfaces changed to become more water-wet. Also, values of IFT between model oil and low-saline brine were measured as 1.1 ± 0.3 and 2.8 ± 0.4 (mN/m) when using the rhamnolipid and SDBS respectively as modifiers within the aqueous solutions. Finally, the outcomes of core flooding experiments revealed that the rhamnolipid surfactant could minimize flow problems arising from the formation of emulsions, leading to 14.98% higher ultimate oil recovery compared to SDBS.
- Thermal analysis and combustion kinetic of heavy oils and their asphaltene and maltene fractions using accelerating rate calorimetry(2014-11-05) Ronaldo Santos; VIDAL, V. J. A.; TREVISAN. O. V.© 2014 American Chemical Society.This work presents an experimental study on the thermal and kinetic parameters of the oxidation reaction of heavy crude oils to support the in-situ combustion oil recovery technique. An accelerated rate calorimeter was used to investigate the thermal behavior of two Brazilian heavy oils in an open system under constant pressure and continuous heating to 550 °C. The goal was to identify and characterize several oxidation regions and to obtain the activation energy and reaction order. The temperature-time curves showed three clearly distinct regions. During the heating, autoignition was found to have started at 180-220 °C. Then, the reaction curves exhibit a strong exothermic behavior up to 250-350 °C, which represents the low-temperature oxidation. Asphaltenes were found to play a crucial role in the kinetic behavior of the crude oils. The results show that oxygen-addition reactions are dominant from 200 to 300 °C and that bond-scission reactions are dominant above 350 °C. Although the presence of sand and clay improves the contact between the oil and oxygen and accelerates both of these reactions, it has a greater impact on the oxygen-addition reactions. The results provide helpful data for the screening of crude oils as candidates for recovery by in-situ combustion.
- A new framework to quantify thewetting behaviour of carbonate rock surfaces based on the relationship between zeta potential and contact angle(2020-01-05) GOMARI, S. R.; AMROUCHE, F.; Ronaldo Santos; GREENWELL, H. C.; CUBILLAS, P.© 2020 by the authors.This study introduces a new framework to quantify the wettability of powdered carbonate rock from existing correlations between zeta potential and contact angle. The new framework has the potential to be faster and cheaper than conventional approaches and could increase confidence in surface wetting quantification, since the results are insensitive to the inherent heterogeneity of rock surfaces. The obtained results from experiments were used to develop a set of equations for determining the carbonate rock contact angle from streaming potential data. The equations were validated for the evaluation of changes in the wettability of carbonate rock using different stearic acid oily solutions. The contact angles calculated from the proposed equations were then compared with measured values on the calcite surface. The results show that the proposed framework was able to quantify the wettability of carbonate rock with an acceptable range of error of about 4%-14%.
- Tire waste management: an overview from chemical compounding to the pyrolysis-derived fuels(2020-05-01) Ronaldo Santos; ROCHA, C.L.; FELIPE, F.L.S.; CEZARIO, F.T.; CORREIA, P.J.; REZAEI-GOMAR, S.© 2020, Springer Japan KK, part of Springer Nature.The management of tire residues is still a challenge for the industry and governments due to the great volume occupied by the tires and the difficulty of recycling associated with the intricate structure. Thermal degradation is a promisor via to avoid the improper disposal of scrap tires. The waste tire conversion into chemicals by means of pyrolysis yields high added-value products that can be used as reaction precursors and fuels. Tire-derived pyrolysis oil can also be mixed with conventional fossil fuels, producing blends with improved fuel properties and reduced cost. This survey describes the tire compound and the feasibility to convert scrap tire into chemical components as an alternative recycling method, focusing on the tire-derived oil. Pyrolysis is discussed as a method to the tire recovery and reuse, preventing environmental damages and contributing to the sustainable cyclic process. The liquid fraction derived from tire pyrolysis is a complex mixture containing valuable compounds, such as alkyl and alkenyl hydrocarbons, polycyclic aromatics, and terpenes. The assessment of the main properties of tire-derived fuels for industrial and automotive applications are highlighted.
- Biomass-derived syngas production via gasification process and its catalytic conversion into fuels by Fischer Tropsch synthesis: A review(2020) Ronaldo Santos; ALENCAR, A. C.© 2019 Hydrogen Energy Publications LLCThe Fischer–Tropsch (FT) synthesis has been investigated over decades as an alternative route to obtain synthetic fuels from synthesis gas. FT is a high-performance synthesis based on metallic catalysis, mainly using ruthenium, cobalt and iron catalysts, which converts syngas in hydrocarbons and chemical precursors. This work presents a review on the aspects of the syngas production from biomass gasification and its subsequent conversion into fuels through the Fischer-Tropsch synthesis. The usage of biomass, including lignocellulosic residues, as a raw material in the gasification process. Biosyngas is highlighted as a synthetic fuel source to replace nonrenewable, conventional fossil fuels. Lignocellulosic material must be considered a low-cost feedstock to the liquid biofuel production on a large scale. Studies on syngas cleaning to attain the purity required by the FT process is revised. Recent understanding of reaction kinetics and thermodynamics has contributed to increasing the FT performance and economic viability. This paper includes also the debate on main catalysts, industrial process requirements, and chemical reaction kinetics and mechanisms of Fischer–Tropsch synthesis.
- Properties of Cellulose Nanofibers Extracted from Eucalyptus and their Emulsifying Role in the Oil-in-Water Pickering Emulsions(2021-06-18) MARTINS, L. S.; Ronaldo Santos; SPINACE, M. A. S.© 2021, The Author(s), under exclusive licence to Springer Nature B.V.In this work, nanocellulose particles were obtained from eucalyptus fibers by high-pressure homogenization (CNF) and by high-intensity ultrasound (SCNF). The nanocellulose was applied as a solid emulsifier for soybean oil in water (O/W) emulsions. The adding of 0.25–1 wt.% of both CNF and SCNF produced stable O/W emulsions without conventional surfactants. SCNF emulsions showed the highest stability and displayed the narrowest size distribution. Zeta potential values (− 40 to − 70 mV) indicated an electrical barrier to the droplet coalescence. The rheological behavior of O/W emulsions stabilized with CNF and SCNF was described by the Herschel-Buckley model. O/W emulsions produced with nanocellulose particles behave as shear thinning fluid, and their behavior index ranged from 0.33 to 0.68. Both CNF and SCNF emulsions displayed maximum yield stress at a particle concentration of 0.5 wt.% and 0.75 wt.%, respectively. Besides, the prepared O/W emulsions using 0.5 to 1.00 wt.% CNF or SCNF did not showed phase separation until 30 days of rest. The data point out to the feasibility of using nanocellulose as a natural emulsifier, which can replace conventional surfactants. Graphic Abstract: [Figure not available: see fulltext.].
- Phase behavior of surface films of SARA fractions extracted from heavy oil(2021-06-05) NEVES, M. A. R.; Ronaldo Santos© 2021 Elsevier B.V.Crude oil amphiphilics have been extensively investigated concerning their colloidal properties related to oilfield operation problems. The interfacial structure and elasticity of oil amphiphilic films built on fluid-fluid interfaces have a powerful effect on the stability and rheology of petroleum emulsions and foams. This work presents a description of interfacial films of amphiphilics extracted from petroleum at water-air interfaces using a Langmuir trough. The investigation evaluates surface pressure - area compression isotherms to describe properly the phase behavior of monolayers formed by SARA fractions on isothermal compression at different subphase pH. The SARA films displayed two distinct phase-transitions in different specific areas, according to the pH of the subphase. At pH 2, the surface pressure follows the order: asphaltene > aromatic > resin > saturate, for specific areas higher than 0.04 m2/mg. At neutral and basic pH, the previous order was changed to asphaltene > resin > aromatic > saturate. The surface pressure for asphaltene films was always higher than the surface pressure for other SARA fractions, which is in agreement with the higher surface activity of crude oil asphaltenes. The occurrence of the first phase transition of asphaltene films varies in the range 0.14–0.19 m2/mg with a maxima surface pressure (πmax) of 37.14 mN/m, whereas the second phase transition was held on range 0.069–0.099 m2/mg with a πmax = 55.23 mN/m. The modulus of elasticity (E) of asphaltene compressed-liquid films was found 65–80 mN/m (expect at pH 4, where E~40 mN/m), which is related to the most compressible films. On the other hand, maltene films of SARA fractions showed almost always modulus of elasticity lower than 20 mN/m for both expanded-liquid and compressed-liquid films. The description of the interfacial film nature must be a useful tool to forecast the film stability in the disperse systems as foams and emulsions according to the SARA composition.
- A New Framework to Quantify the Wetting Behaviour of Carbonate Rock Surfaces Based on the Relationship between Zeta Potential and Contact Angle(2020-02-23) REZAEI-GOMARI, SINA; AMROUCHE, FARIDA; Ronaldo Santos; GREENWELL, HUGH CHRISTOPHER; CUBILLAS, PABLOThis study introduces a new framework to quantify the wettability of powdered carbonate rock from existing correlations between zeta potential and contact angle. The new framework has the potential to be faster and cheaper than conventional approaches and could increase confidence in surface wetting quantification, since the results are insensitive to the inherent heterogeneity of rock surfaces. The obtained results from experiments were used to develop a set of equations for determining the carbonate rock contact angle from streaming potential data. The equations were validated for the evaluation of changes in the wettability of carbonate rock using different stearic acid oily solutions. The contact angles calculated from the proposed equations were then compared with measured values on the calcite surface. The results show that the proposed framework was able to quantify the wettability of carbonate rock with an acceptable range of error of about 4%–14%.