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Densities, speeds of sound, and refractive indices of methyl laurate, ethyl laurate, ethyl myristate, and ethyl oleate in the temperature range 288.15−343.15 K and viscosities from 288.15 to 373.15 K were measured at atmospheric pressure. The measured properties were in good agreement with several available literature data, finding an overall absolute average percentage deviation (AAD) of 0.04%, 0.07%, 3%, and 0.1% for density, speed of sound, viscosity, and refractive index, respectively. The densities of mentioned esters were also measured along 15 isotherms from 293.15 to 413.15 K and at pressures up to 60 MPa using an Anton Paar DMA HP densimeter. Based on the literature data selected for comparison, in the studied ranges of temperature and pressure, the AADs of high-pressure densities were 0.08% for methyl laurate, 0.06% for ethyl laurate, and 0.05% for ethyl myristate. The obtained density values were correlated through the modified Tammann−Tait equation with an AAD lower than 0.009% for all the studied esters. The adjusted parameters were used to calculate the isothermal compressibility, isobaric thermal expansivity, internal pressure, and difference in isobaric and isochoric heat capacities. It was found that methyl laurate has higher density, speed of sound, and refractive index than ethyl laurate of the same fatty acid, while viscosities for the ethyl are slightly higher than those of the methyl laurate. The values of the isothermal compressibility and the isobaric thermal expansivity for ethyl laurate are slightly higher than those for methyl.

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The new approach for simulation and optimization of a continuous catalytic regenerative (CCR) reformer process is proposed. Typical CCR reforming processes consist of three to four reactors with recycle. The reaction patterns and reactors are typically modeled using a system of partial differential equations (PDEs). The numerical simulation solution of the entire model for a process system consisting of multiple reaction zones with recycle is extremely time-consuming and, thus, impractical in optimization studies. That is why we proposed a more efficient simulation and optimization scheme based on quasi-steady-state assumptions. We define criteria for reactor fragmentation to avoid the introduction of large errors in the quasi-steady-state calculations. The optimization problem is formulated with the objective of minimizing fuel consumption. The employed objective function constitutes a combined measure for economic and environmental performance. It is shown that the proposed approach identifies considerable improvements for the process.

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